1/* 2** 2001-09-15 3** 4** The author disclaims copyright to this source code. In place of 5** a legal notice, here is a blessing: 6** 7** May you do good and not evil. 8** May you find forgiveness for yourself and forgive others. 9** May you share freely, never taking more than you give. 10** 11************************************************************************* 12** This header file defines the interface that the SQLite library 13** presents to client programs. If a C-function, structure, datatype, 14** or constant definition does not appear in this file, then it is 15** not a published API of SQLite, is subject to change without 16** notice, and should not be referenced by programs that use SQLite. 17** 18** Some of the definitions that are in this file are marked as 19** "experimental". Experimental interfaces are normally new 20** features recently added to SQLite. We do not anticipate changes 21** to experimental interfaces but reserve the right to make minor changes 22** if experience from use "in the wild" suggest such changes are prudent. 23** 24** The official C-language API documentation for SQLite is derived 25** from comments in this file. This file is the authoritative source 26** on how SQLite interfaces are supposed to operate. 27** 28** The name of this file under configuration management is "sqlite.h.in". 29** The makefile makes some minor changes to this file (such as inserting 30** the version number) and changes its name to "sqlite3.h" as 31** part of the build process. 32*/ 33#ifndef SQLITE3_H 34#define SQLITE3_H 35#include <stdarg.h> /* Needed for the definition of va_list */ 36 37/* 38** Make sure we can call this stuff from C++. 39*/ 40#ifdef __cplusplus 41extern "C" { 42#endif 43 44 45/* 46** Facilitate override of interface linkage and calling conventions. 47** Be aware that these macros may not be used within this particular 48** translation of the amalgamation and its associated header file. 49** 50** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the 51** compiler that the target identifier should have external linkage. 52** 53** The SQLITE_CDECL macro is used to set the calling convention for 54** public functions that accept a variable number of arguments. 55** 56** The SQLITE_APICALL macro is used to set the calling convention for 57** public functions that accept a fixed number of arguments. 58** 59** The SQLITE_STDCALL macro is no longer used and is now deprecated. 60** 61** The SQLITE_CALLBACK macro is used to set the calling convention for 62** function pointers. 63** 64** The SQLITE_SYSAPI macro is used to set the calling convention for 65** functions provided by the operating system. 66** 67** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and 68** SQLITE_SYSAPI macros are used only when building for environments 69** that require non-default calling conventions. 70*/ 71#ifndef SQLITE_EXTERN 72# define SQLITE_EXTERN extern 73#endif 74#ifndef SQLITE_API 75# define SQLITE_API 76#endif 77#ifndef SQLITE_CDECL 78# define SQLITE_CDECL 79#endif 80#ifndef SQLITE_APICALL 81# define SQLITE_APICALL 82#endif 83#ifndef SQLITE_STDCALL 84# define SQLITE_STDCALL SQLITE_APICALL 85#endif 86#ifndef SQLITE_CALLBACK 87# define SQLITE_CALLBACK 88#endif 89#ifndef SQLITE_SYSAPI 90# define SQLITE_SYSAPI 91#endif 92 93/* 94** These no-op macros are used in front of interfaces to mark those 95** interfaces as either deprecated or experimental. New applications 96** should not use deprecated interfaces - they are supported for backwards 97** compatibility only. Application writers should be aware that 98** experimental interfaces are subject to change in point releases. 99** 100** These macros used to resolve to various kinds of compiler magic that 101** would generate warning messages when they were used. But that 102** compiler magic ended up generating such a flurry of bug reports 103** that we have taken it all out and gone back to using simple 104** noop macros. 105*/ 106#define SQLITE_DEPRECATED 107#define SQLITE_EXPERIMENTAL 108 109/* 110** Ensure these symbols were not defined by some previous header file. 111*/ 112#ifdef SQLITE_VERSION 113# undef SQLITE_VERSION 114#endif 115#ifdef SQLITE_VERSION_NUMBER 116# undef SQLITE_VERSION_NUMBER 117#endif 118 119/* 120** CAPI3REF: Compile-Time Library Version Numbers 121** 122** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 123** evaluates to a string literal that is the SQLite version in the 124** format "X.Y.Z" where X is the major version number (always 3 for 125** SQLite3) and Y is the minor version number and Z is the release number.)^ 126** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 127** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 128** numbers used in [SQLITE_VERSION].)^ 129** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 130** be larger than the release from which it is derived. Either Y will 131** be held constant and Z will be incremented or else Y will be incremented 132** and Z will be reset to zero. 133** 134** Since [version 3.6.18] ([dateof:3.6.18]), 135** SQLite source code has been stored in the 136** <a href="http://www.fossil-scm.org/">Fossil configuration management 137** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 138** a string which identifies a particular check-in of SQLite 139** within its configuration management system. ^The SQLITE_SOURCE_ID 140** string contains the date and time of the check-in (UTC) and a SHA1 141** or SHA3-256 hash of the entire source tree. If the source code has 142** been edited in any way since it was last checked in, then the last 143** four hexadecimal digits of the hash may be modified. 144** 145** See also: [sqlite3_libversion()], 146** [sqlite3_libversion_number()], [sqlite3_sourceid()], 147** [sqlite_version()] and [sqlite_source_id()]. 148*/ 149#define SQLITE_VERSION "--VERS--" 150#define SQLITE_VERSION_NUMBER --VERSION-NUMBER-- 151#define SQLITE_SOURCE_ID "--SOURCE-ID--" 152 153/* 154** CAPI3REF: Run-Time Library Version Numbers 155** KEYWORDS: sqlite3_version sqlite3_sourceid 156** 157** These interfaces provide the same information as the [SQLITE_VERSION], 158** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 159** but are associated with the library instead of the header file. ^(Cautious 160** programmers might include assert() statements in their application to 161** verify that values returned by these interfaces match the macros in 162** the header, and thus ensure that the application is 163** compiled with matching library and header files. 164** 165** <blockquote><pre> 166** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 167** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 168** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 169** </pre></blockquote>)^ 170** 171** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 172** macro. ^The sqlite3_libversion() function returns a pointer to the 173** to the sqlite3_version[] string constant. The sqlite3_libversion() 174** function is provided for use in DLLs since DLL users usually do not have 175** direct access to string constants within the DLL. ^The 176** sqlite3_libversion_number() function returns an integer equal to 177** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 178** a pointer to a string constant whose value is the same as the 179** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 180** using an edited copy of [the amalgamation], then the last four characters 181** of the hash might be different from [SQLITE_SOURCE_ID].)^ 182** 183** See also: [sqlite_version()] and [sqlite_source_id()]. 184*/ 185SQLITE_EXTERN const char sqlite3_version[]; 186const char *sqlite3_libversion(void); 187const char *sqlite3_sourceid(void); 188int sqlite3_libversion_number(void); 189 190/* 191** CAPI3REF: Run-Time Library Compilation Options Diagnostics 192** 193** ^The sqlite3_compileoption_used() function returns 0 or 1 194** indicating whether the specified option was defined at 195** compile time. ^The SQLITE_ prefix may be omitted from the 196** option name passed to sqlite3_compileoption_used(). 197** 198** ^The sqlite3_compileoption_get() function allows iterating 199** over the list of options that were defined at compile time by 200** returning the N-th compile time option string. ^If N is out of range, 201** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 202** prefix is omitted from any strings returned by 203** sqlite3_compileoption_get(). 204** 205** ^Support for the diagnostic functions sqlite3_compileoption_used() 206** and sqlite3_compileoption_get() may be omitted by specifying the 207** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 208** 209** See also: SQL functions [sqlite_compileoption_used()] and 210** [sqlite_compileoption_get()] and the [compile_options pragma]. 211*/ 212#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 213int sqlite3_compileoption_used(const char *zOptName); 214const char *sqlite3_compileoption_get(int N); 215#else 216# define sqlite3_compileoption_used(X) 0 217# define sqlite3_compileoption_get(X) ((void*)0) 218#endif 219 220/* 221** CAPI3REF: Test To See If The Library Is Threadsafe 222** 223** ^The sqlite3_threadsafe() function returns zero if and only if 224** SQLite was compiled with mutexing code omitted due to the 225** [SQLITE_THREADSAFE] compile-time option being set to 0. 226** 227** SQLite can be compiled with or without mutexes. When 228** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 229** are enabled and SQLite is threadsafe. When the 230** [SQLITE_THREADSAFE] macro is 0, 231** the mutexes are omitted. Without the mutexes, it is not safe 232** to use SQLite concurrently from more than one thread. 233** 234** Enabling mutexes incurs a measurable performance penalty. 235** So if speed is of utmost importance, it makes sense to disable 236** the mutexes. But for maximum safety, mutexes should be enabled. 237** ^The default behavior is for mutexes to be enabled. 238** 239** This interface can be used by an application to make sure that the 240** version of SQLite that it is linking against was compiled with 241** the desired setting of the [SQLITE_THREADSAFE] macro. 242** 243** This interface only reports on the compile-time mutex setting 244** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 245** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 246** can be fully or partially disabled using a call to [sqlite3_config()] 247** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 248** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 249** sqlite3_threadsafe() function shows only the compile-time setting of 250** thread safety, not any run-time changes to that setting made by 251** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 252** is unchanged by calls to sqlite3_config().)^ 253** 254** See the [threading mode] documentation for additional information. 255*/ 256int sqlite3_threadsafe(void); 257 258/* 259** CAPI3REF: Database Connection Handle 260** KEYWORDS: {database connection} {database connections} 261** 262** Each open SQLite database is represented by a pointer to an instance of 263** the opaque structure named "sqlite3". It is useful to think of an sqlite3 264** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 265** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 266** and [sqlite3_close_v2()] are its destructors. There are many other 267** interfaces (such as 268** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 269** [sqlite3_busy_timeout()] to name but three) that are methods on an 270** sqlite3 object. 271*/ 272typedef struct sqlite3 sqlite3; 273 274/* 275** CAPI3REF: 64-Bit Integer Types 276** KEYWORDS: sqlite_int64 sqlite_uint64 277** 278** Because there is no cross-platform way to specify 64-bit integer types 279** SQLite includes typedefs for 64-bit signed and unsigned integers. 280** 281** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 282** The sqlite_int64 and sqlite_uint64 types are supported for backwards 283** compatibility only. 284** 285** ^The sqlite3_int64 and sqlite_int64 types can store integer values 286** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 287** sqlite3_uint64 and sqlite_uint64 types can store integer values 288** between 0 and +18446744073709551615 inclusive. 289*/ 290#ifdef SQLITE_INT64_TYPE 291 typedef SQLITE_INT64_TYPE sqlite_int64; 292# ifdef SQLITE_UINT64_TYPE 293 typedef SQLITE_UINT64_TYPE sqlite_uint64; 294# else 295 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 296# endif 297#elif defined(_MSC_VER) || defined(__BORLANDC__) 298 typedef __int64 sqlite_int64; 299 typedef unsigned __int64 sqlite_uint64; 300#else 301 typedef long long int sqlite_int64; 302 typedef unsigned long long int sqlite_uint64; 303#endif 304typedef sqlite_int64 sqlite3_int64; 305typedef sqlite_uint64 sqlite3_uint64; 306 307/* 308** If compiling for a processor that lacks floating point support, 309** substitute integer for floating-point. 310*/ 311#ifdef SQLITE_OMIT_FLOATING_POINT 312# define double sqlite3_int64 313#endif 314 315/* 316** CAPI3REF: Closing A Database Connection 317** DESTRUCTOR: sqlite3 318** 319** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 320** for the [sqlite3] object. 321** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 322** the [sqlite3] object is successfully destroyed and all associated 323** resources are deallocated. 324** 325** Ideally, applications should [sqlite3_finalize | finalize] all 326** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 327** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 328** with the [sqlite3] object prior to attempting to close the object. 329** ^If the database connection is associated with unfinalized prepared 330** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then 331** sqlite3_close() will leave the database connection open and return 332** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared 333** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, 334** it returns [SQLITE_OK] regardless, but instead of deallocating the database 335** connection immediately, it marks the database connection as an unusable 336** "zombie" and makes arrangements to automatically deallocate the database 337** connection after all prepared statements are finalized, all BLOB handles 338** are closed, and all backups have finished. The sqlite3_close_v2() interface 339** is intended for use with host languages that are garbage collected, and 340** where the order in which destructors are called is arbitrary. 341** 342** ^If an [sqlite3] object is destroyed while a transaction is open, 343** the transaction is automatically rolled back. 344** 345** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 346** must be either a NULL 347** pointer or an [sqlite3] object pointer obtained 348** from [sqlite3_open()], [sqlite3_open16()], or 349** [sqlite3_open_v2()], and not previously closed. 350** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 351** argument is a harmless no-op. 352*/ 353int sqlite3_close(sqlite3*); 354int sqlite3_close_v2(sqlite3*); 355 356/* 357** The type for a callback function. 358** This is legacy and deprecated. It is included for historical 359** compatibility and is not documented. 360*/ 361typedef int (*sqlite3_callback)(void*,int,char**, char**); 362 363/* 364** CAPI3REF: One-Step Query Execution Interface 365** METHOD: sqlite3 366** 367** The sqlite3_exec() interface is a convenience wrapper around 368** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 369** that allows an application to run multiple statements of SQL 370** without having to use a lot of C code. 371** 372** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 373** semicolon-separate SQL statements passed into its 2nd argument, 374** in the context of the [database connection] passed in as its 1st 375** argument. ^If the callback function of the 3rd argument to 376** sqlite3_exec() is not NULL, then it is invoked for each result row 377** coming out of the evaluated SQL statements. ^The 4th argument to 378** sqlite3_exec() is relayed through to the 1st argument of each 379** callback invocation. ^If the callback pointer to sqlite3_exec() 380** is NULL, then no callback is ever invoked and result rows are 381** ignored. 382** 383** ^If an error occurs while evaluating the SQL statements passed into 384** sqlite3_exec(), then execution of the current statement stops and 385** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 386** is not NULL then any error message is written into memory obtained 387** from [sqlite3_malloc()] and passed back through the 5th parameter. 388** To avoid memory leaks, the application should invoke [sqlite3_free()] 389** on error message strings returned through the 5th parameter of 390** sqlite3_exec() after the error message string is no longer needed. 391** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 392** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 393** NULL before returning. 394** 395** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 396** routine returns SQLITE_ABORT without invoking the callback again and 397** without running any subsequent SQL statements. 398** 399** ^The 2nd argument to the sqlite3_exec() callback function is the 400** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 401** callback is an array of pointers to strings obtained as if from 402** [sqlite3_column_text()], one for each column. ^If an element of a 403** result row is NULL then the corresponding string pointer for the 404** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 405** sqlite3_exec() callback is an array of pointers to strings where each 406** entry represents the name of corresponding result column as obtained 407** from [sqlite3_column_name()]. 408** 409** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 410** to an empty string, or a pointer that contains only whitespace and/or 411** SQL comments, then no SQL statements are evaluated and the database 412** is not changed. 413** 414** Restrictions: 415** 416** <ul> 417** <li> The application must ensure that the 1st parameter to sqlite3_exec() 418** is a valid and open [database connection]. 419** <li> The application must not close the [database connection] specified by 420** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 421** <li> The application must not modify the SQL statement text passed into 422** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 423** </ul> 424*/ 425int sqlite3_exec( 426 sqlite3*, /* An open database */ 427 const char *sql, /* SQL to be evaluated */ 428 int (*callback)(void*,int,char**,char**), /* Callback function */ 429 void *, /* 1st argument to callback */ 430 char **errmsg /* Error msg written here */ 431); 432 433/* 434** CAPI3REF: Result Codes 435** KEYWORDS: {result code definitions} 436** 437** Many SQLite functions return an integer result code from the set shown 438** here in order to indicate success or failure. 439** 440** New error codes may be added in future versions of SQLite. 441** 442** See also: [extended result code definitions] 443*/ 444#define SQLITE_OK 0 /* Successful result */ 445/* beginning-of-error-codes */ 446#define SQLITE_ERROR 1 /* Generic error */ 447#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 448#define SQLITE_PERM 3 /* Access permission denied */ 449#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 450#define SQLITE_BUSY 5 /* The database file is locked */ 451#define SQLITE_LOCKED 6 /* A table in the database is locked */ 452#define SQLITE_NOMEM 7 /* A malloc() failed */ 453#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 454#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 455#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 456#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 457#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 458#define SQLITE_FULL 13 /* Insertion failed because database is full */ 459#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 460#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 461#define SQLITE_EMPTY 16 /* Internal use only */ 462#define SQLITE_SCHEMA 17 /* The database schema changed */ 463#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 464#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 465#define SQLITE_MISMATCH 20 /* Data type mismatch */ 466#define SQLITE_MISUSE 21 /* Library used incorrectly */ 467#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 468#define SQLITE_AUTH 23 /* Authorization denied */ 469#define SQLITE_FORMAT 24 /* Not used */ 470#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 471#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 472#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 473#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 474#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 475#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 476/* end-of-error-codes */ 477 478/* 479** CAPI3REF: Extended Result Codes 480** KEYWORDS: {extended result code definitions} 481** 482** In its default configuration, SQLite API routines return one of 30 integer 483** [result codes]. However, experience has shown that many of 484** these result codes are too coarse-grained. They do not provide as 485** much information about problems as programmers might like. In an effort to 486** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 487** and later) include 488** support for additional result codes that provide more detailed information 489** about errors. These [extended result codes] are enabled or disabled 490** on a per database connection basis using the 491** [sqlite3_extended_result_codes()] API. Or, the extended code for 492** the most recent error can be obtained using 493** [sqlite3_extended_errcode()]. 494*/ 495#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 496#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 497#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 498#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 499#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 500#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 501#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 502#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 503#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 504#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 505#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 506#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 507#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 508#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 509#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 510#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 511#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 512#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 513#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 514#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 515#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 516#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 517#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 518#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 519#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 520#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 521#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 522#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 523#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 524#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 525#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 526#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 527#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 528#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 529#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) 530#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) 531#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 532#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 533#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 534#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 535#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) 536#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 537#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 538#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 539#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 540#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 541#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 542#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 543#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 544#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 545#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 546#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 547#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 548#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 549#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 550#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 551#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 552#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 553#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 554#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 555#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 556#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 557#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 558#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 559#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 560#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 561#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 562#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 563#define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) 564#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 565#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 566#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 567#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 568#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 569#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */ 570 571/* 572** CAPI3REF: Flags For File Open Operations 573** 574** These bit values are intended for use in the 575** 3rd parameter to the [sqlite3_open_v2()] interface and 576** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 577** 578** Only those flags marked as "Ok for sqlite3_open_v2()" may be 579** used as the third argument to the [sqlite3_open_v2()] interface. 580** The other flags have historically been ignored by sqlite3_open_v2(), 581** though future versions of SQLite might change so that an error is 582** raised if any of the disallowed bits are passed into sqlite3_open_v2(). 583** Applications should not depend on the historical behavior. 584** 585** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into 586** [sqlite3_open_v2()] does *not* cause the underlying database file 587** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into 588** [sqlite3_open_v2()] has historically be a no-op and might become an 589** error in future versions of SQLite. 590*/ 591#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 592#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 593#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 594#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 595#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 596#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 597#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 598#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 599#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 600#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 601#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 602#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 603#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 604#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 605#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 606#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 607#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 608#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 609#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 610#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 611#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 612#define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ 613 614/* Reserved: 0x00F00000 */ 615/* Legacy compatibility: */ 616#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 617 618 619/* 620** CAPI3REF: Device Characteristics 621** 622** The xDeviceCharacteristics method of the [sqlite3_io_methods] 623** object returns an integer which is a vector of these 624** bit values expressing I/O characteristics of the mass storage 625** device that holds the file that the [sqlite3_io_methods] 626** refers to. 627** 628** The SQLITE_IOCAP_ATOMIC property means that all writes of 629** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 630** mean that writes of blocks that are nnn bytes in size and 631** are aligned to an address which is an integer multiple of 632** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 633** that when data is appended to a file, the data is appended 634** first then the size of the file is extended, never the other 635** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 636** information is written to disk in the same order as calls 637** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 638** after reboot following a crash or power loss, the only bytes in a 639** file that were written at the application level might have changed 640** and that adjacent bytes, even bytes within the same sector are 641** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 642** flag indicates that a file cannot be deleted when open. The 643** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 644** read-only media and cannot be changed even by processes with 645** elevated privileges. 646** 647** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 648** filesystem supports doing multiple write operations atomically when those 649** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 650** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 651*/ 652#define SQLITE_IOCAP_ATOMIC 0x00000001 653#define SQLITE_IOCAP_ATOMIC512 0x00000002 654#define SQLITE_IOCAP_ATOMIC1K 0x00000004 655#define SQLITE_IOCAP_ATOMIC2K 0x00000008 656#define SQLITE_IOCAP_ATOMIC4K 0x00000010 657#define SQLITE_IOCAP_ATOMIC8K 0x00000020 658#define SQLITE_IOCAP_ATOMIC16K 0x00000040 659#define SQLITE_IOCAP_ATOMIC32K 0x00000080 660#define SQLITE_IOCAP_ATOMIC64K 0x00000100 661#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 662#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 663#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 664#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 665#define SQLITE_IOCAP_IMMUTABLE 0x00002000 666#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 667 668/* 669** CAPI3REF: File Locking Levels 670** 671** SQLite uses one of these integer values as the second 672** argument to calls it makes to the xLock() and xUnlock() methods 673** of an [sqlite3_io_methods] object. These values are ordered from 674** lest restrictive to most restrictive. 675** 676** The argument to xLock() is always SHARED or higher. The argument to 677** xUnlock is either SHARED or NONE. 678*/ 679#define SQLITE_LOCK_NONE 0 /* xUnlock() only */ 680#define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ 681#define SQLITE_LOCK_RESERVED 2 /* xLock() only */ 682#define SQLITE_LOCK_PENDING 3 /* xLock() only */ 683#define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ 684 685/* 686** CAPI3REF: Synchronization Type Flags 687** 688** When SQLite invokes the xSync() method of an 689** [sqlite3_io_methods] object it uses a combination of 690** these integer values as the second argument. 691** 692** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 693** sync operation only needs to flush data to mass storage. Inode 694** information need not be flushed. If the lower four bits of the flag 695** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 696** If the lower four bits equal SQLITE_SYNC_FULL, that means 697** to use Mac OS X style fullsync instead of fsync(). 698** 699** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 700** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 701** settings. The [synchronous pragma] determines when calls to the 702** xSync VFS method occur and applies uniformly across all platforms. 703** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 704** energetic or rigorous or forceful the sync operations are and 705** only make a difference on Mac OSX for the default SQLite code. 706** (Third-party VFS implementations might also make the distinction 707** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 708** operating systems natively supported by SQLite, only Mac OSX 709** cares about the difference.) 710*/ 711#define SQLITE_SYNC_NORMAL 0x00002 712#define SQLITE_SYNC_FULL 0x00003 713#define SQLITE_SYNC_DATAONLY 0x00010 714 715/* 716** CAPI3REF: OS Interface Open File Handle 717** 718** An [sqlite3_file] object represents an open file in the 719** [sqlite3_vfs | OS interface layer]. Individual OS interface 720** implementations will 721** want to subclass this object by appending additional fields 722** for their own use. The pMethods entry is a pointer to an 723** [sqlite3_io_methods] object that defines methods for performing 724** I/O operations on the open file. 725*/ 726typedef struct sqlite3_file sqlite3_file; 727struct sqlite3_file { 728 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 729}; 730 731/* 732** CAPI3REF: OS Interface File Virtual Methods Object 733** 734** Every file opened by the [sqlite3_vfs.xOpen] method populates an 735** [sqlite3_file] object (or, more commonly, a subclass of the 736** [sqlite3_file] object) with a pointer to an instance of this object. 737** This object defines the methods used to perform various operations 738** against the open file represented by the [sqlite3_file] object. 739** 740** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 741** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 742** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 743** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 744** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 745** to NULL. 746** 747** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 748** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 749** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 750** flag may be ORed in to indicate that only the data of the file 751** and not its inode needs to be synced. 752** 753** The integer values to xLock() and xUnlock() are one of 754** <ul> 755** <li> [SQLITE_LOCK_NONE], 756** <li> [SQLITE_LOCK_SHARED], 757** <li> [SQLITE_LOCK_RESERVED], 758** <li> [SQLITE_LOCK_PENDING], or 759** <li> [SQLITE_LOCK_EXCLUSIVE]. 760** </ul> 761** xLock() upgrades the database file lock. In other words, xLock() moves the 762** database file lock in the direction NONE toward EXCLUSIVE. The argument to 763** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never 764** SQLITE_LOCK_NONE. If the database file lock is already at or above the 765** requested lock, then the call to xLock() is a no-op. 766** xUnlock() downgrades the database file lock to either SHARED or NONE. 767* If the lock is already at or below the requested lock state, then the call 768** to xUnlock() is a no-op. 769** The xCheckReservedLock() method checks whether any database connection, 770** either in this process or in some other process, is holding a RESERVED, 771** PENDING, or EXCLUSIVE lock on the file. It returns true 772** if such a lock exists and false otherwise. 773** 774** The xFileControl() method is a generic interface that allows custom 775** VFS implementations to directly control an open file using the 776** [sqlite3_file_control()] interface. The second "op" argument is an 777** integer opcode. The third argument is a generic pointer intended to 778** point to a structure that may contain arguments or space in which to 779** write return values. Potential uses for xFileControl() might be 780** functions to enable blocking locks with timeouts, to change the 781** locking strategy (for example to use dot-file locks), to inquire 782** about the status of a lock, or to break stale locks. The SQLite 783** core reserves all opcodes less than 100 for its own use. 784** A [file control opcodes | list of opcodes] less than 100 is available. 785** Applications that define a custom xFileControl method should use opcodes 786** greater than 100 to avoid conflicts. VFS implementations should 787** return [SQLITE_NOTFOUND] for file control opcodes that they do not 788** recognize. 789** 790** The xSectorSize() method returns the sector size of the 791** device that underlies the file. The sector size is the 792** minimum write that can be performed without disturbing 793** other bytes in the file. The xDeviceCharacteristics() 794** method returns a bit vector describing behaviors of the 795** underlying device: 796** 797** <ul> 798** <li> [SQLITE_IOCAP_ATOMIC] 799** <li> [SQLITE_IOCAP_ATOMIC512] 800** <li> [SQLITE_IOCAP_ATOMIC1K] 801** <li> [SQLITE_IOCAP_ATOMIC2K] 802** <li> [SQLITE_IOCAP_ATOMIC4K] 803** <li> [SQLITE_IOCAP_ATOMIC8K] 804** <li> [SQLITE_IOCAP_ATOMIC16K] 805** <li> [SQLITE_IOCAP_ATOMIC32K] 806** <li> [SQLITE_IOCAP_ATOMIC64K] 807** <li> [SQLITE_IOCAP_SAFE_APPEND] 808** <li> [SQLITE_IOCAP_SEQUENTIAL] 809** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 810** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 811** <li> [SQLITE_IOCAP_IMMUTABLE] 812** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 813** </ul> 814** 815** The SQLITE_IOCAP_ATOMIC property means that all writes of 816** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 817** mean that writes of blocks that are nnn bytes in size and 818** are aligned to an address which is an integer multiple of 819** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 820** that when data is appended to a file, the data is appended 821** first then the size of the file is extended, never the other 822** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 823** information is written to disk in the same order as calls 824** to xWrite(). 825** 826** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 827** in the unread portions of the buffer with zeros. A VFS that 828** fails to zero-fill short reads might seem to work. However, 829** failure to zero-fill short reads will eventually lead to 830** database corruption. 831*/ 832typedef struct sqlite3_io_methods sqlite3_io_methods; 833struct sqlite3_io_methods { 834 int iVersion; 835 int (*xClose)(sqlite3_file*); 836 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 837 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 838 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 839 int (*xSync)(sqlite3_file*, int flags); 840 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 841 int (*xLock)(sqlite3_file*, int); 842 int (*xUnlock)(sqlite3_file*, int); 843 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 844 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 845 int (*xSectorSize)(sqlite3_file*); 846 int (*xDeviceCharacteristics)(sqlite3_file*); 847 /* Methods above are valid for version 1 */ 848 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 849 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 850 void (*xShmBarrier)(sqlite3_file*); 851 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 852 /* Methods above are valid for version 2 */ 853 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 854 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 855 /* Methods above are valid for version 3 */ 856 /* Additional methods may be added in future releases */ 857}; 858 859/* 860** CAPI3REF: Standard File Control Opcodes 861** KEYWORDS: {file control opcodes} {file control opcode} 862** 863** These integer constants are opcodes for the xFileControl method 864** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 865** interface. 866** 867** <ul> 868** <li>[[SQLITE_FCNTL_LOCKSTATE]] 869** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 870** opcode causes the xFileControl method to write the current state of 871** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 872** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 873** into an integer that the pArg argument points to. 874** This capability is only available if SQLite is compiled with [SQLITE_DEBUG]. 875** 876** <li>[[SQLITE_FCNTL_SIZE_HINT]] 877** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 878** layer a hint of how large the database file will grow to be during the 879** current transaction. This hint is not guaranteed to be accurate but it 880** is often close. The underlying VFS might choose to preallocate database 881** file space based on this hint in order to help writes to the database 882** file run faster. 883** 884** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 885** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 886** implements [sqlite3_deserialize()] to set an upper bound on the size 887** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 888** If the integer pointed to is negative, then it is filled in with the 889** current limit. Otherwise the limit is set to the larger of the value 890** of the integer pointed to and the current database size. The integer 891** pointed to is set to the new limit. 892** 893** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 894** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 895** extends and truncates the database file in chunks of a size specified 896** by the user. The fourth argument to [sqlite3_file_control()] should 897** point to an integer (type int) containing the new chunk-size to use 898** for the nominated database. Allocating database file space in large 899** chunks (say 1MB at a time), may reduce file-system fragmentation and 900** improve performance on some systems. 901** 902** <li>[[SQLITE_FCNTL_FILE_POINTER]] 903** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 904** to the [sqlite3_file] object associated with a particular database 905** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 906** 907** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 908** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 909** to the [sqlite3_file] object associated with the journal file (either 910** the [rollback journal] or the [write-ahead log]) for a particular database 911** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 912** 913** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 914** No longer in use. 915** 916** <li>[[SQLITE_FCNTL_SYNC]] 917** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 918** sent to the VFS immediately before the xSync method is invoked on a 919** database file descriptor. Or, if the xSync method is not invoked 920** because the user has configured SQLite with 921** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 922** of the xSync method. In most cases, the pointer argument passed with 923** this file-control is NULL. However, if the database file is being synced 924** as part of a multi-database commit, the argument points to a nul-terminated 925** string containing the transactions super-journal file name. VFSes that 926** do not need this signal should silently ignore this opcode. Applications 927** should not call [sqlite3_file_control()] with this opcode as doing so may 928** disrupt the operation of the specialized VFSes that do require it. 929** 930** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 931** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 932** and sent to the VFS after a transaction has been committed immediately 933** but before the database is unlocked. VFSes that do not need this signal 934** should silently ignore this opcode. Applications should not call 935** [sqlite3_file_control()] with this opcode as doing so may disrupt the 936** operation of the specialized VFSes that do require it. 937** 938** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 939** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 940** retry counts and intervals for certain disk I/O operations for the 941** windows [VFS] in order to provide robustness in the presence of 942** anti-virus programs. By default, the windows VFS will retry file read, 943** file write, and file delete operations up to 10 times, with a delay 944** of 25 milliseconds before the first retry and with the delay increasing 945** by an additional 25 milliseconds with each subsequent retry. This 946** opcode allows these two values (10 retries and 25 milliseconds of delay) 947** to be adjusted. The values are changed for all database connections 948** within the same process. The argument is a pointer to an array of two 949** integers where the first integer is the new retry count and the second 950** integer is the delay. If either integer is negative, then the setting 951** is not changed but instead the prior value of that setting is written 952** into the array entry, allowing the current retry settings to be 953** interrogated. The zDbName parameter is ignored. 954** 955** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 956** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 957** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 958** write ahead log ([WAL file]) and shared memory 959** files used for transaction control 960** are automatically deleted when the latest connection to the database 961** closes. Setting persistent WAL mode causes those files to persist after 962** close. Persisting the files is useful when other processes that do not 963** have write permission on the directory containing the database file want 964** to read the database file, as the WAL and shared memory files must exist 965** in order for the database to be readable. The fourth parameter to 966** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 967** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 968** WAL mode. If the integer is -1, then it is overwritten with the current 969** WAL persistence setting. 970** 971** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 972** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 973** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 974** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 975** xDeviceCharacteristics methods. The fourth parameter to 976** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 977** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 978** mode. If the integer is -1, then it is overwritten with the current 979** zero-damage mode setting. 980** 981** <li>[[SQLITE_FCNTL_OVERWRITE]] 982** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 983** a write transaction to indicate that, unless it is rolled back for some 984** reason, the entire database file will be overwritten by the current 985** transaction. This is used by VACUUM operations. 986** 987** <li>[[SQLITE_FCNTL_VFSNAME]] 988** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 989** all [VFSes] in the VFS stack. The names are of all VFS shims and the 990** final bottom-level VFS are written into memory obtained from 991** [sqlite3_malloc()] and the result is stored in the char* variable 992** that the fourth parameter of [sqlite3_file_control()] points to. 993** The caller is responsible for freeing the memory when done. As with 994** all file-control actions, there is no guarantee that this will actually 995** do anything. Callers should initialize the char* variable to a NULL 996** pointer in case this file-control is not implemented. This file-control 997** is intended for diagnostic use only. 998** 999** <li>[[SQLITE_FCNTL_VFS_POINTER]] 1000** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 1001** [VFSes] currently in use. ^(The argument X in 1002** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 1003** of type "[sqlite3_vfs] **". This opcodes will set *X 1004** to a pointer to the top-level VFS.)^ 1005** ^When there are multiple VFS shims in the stack, this opcode finds the 1006** upper-most shim only. 1007** 1008** <li>[[SQLITE_FCNTL_PRAGMA]] 1009** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 1010** file control is sent to the open [sqlite3_file] object corresponding 1011** to the database file to which the pragma statement refers. ^The argument 1012** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 1013** pointers to strings (char**) in which the second element of the array 1014** is the name of the pragma and the third element is the argument to the 1015** pragma or NULL if the pragma has no argument. ^The handler for an 1016** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 1017** of the char** argument point to a string obtained from [sqlite3_mprintf()] 1018** or the equivalent and that string will become the result of the pragma or 1019** the error message if the pragma fails. ^If the 1020** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 1021** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 1022** file control returns [SQLITE_OK], then the parser assumes that the 1023** VFS has handled the PRAGMA itself and the parser generates a no-op 1024** prepared statement if result string is NULL, or that returns a copy 1025** of the result string if the string is non-NULL. 1026** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 1027** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 1028** that the VFS encountered an error while handling the [PRAGMA] and the 1029** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 1030** file control occurs at the beginning of pragma statement analysis and so 1031** it is able to override built-in [PRAGMA] statements. 1032** 1033** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 1034** ^The [SQLITE_FCNTL_BUSYHANDLER] 1035** file-control may be invoked by SQLite on the database file handle 1036** shortly after it is opened in order to provide a custom VFS with access 1037** to the connection's busy-handler callback. The argument is of type (void**) 1038** - an array of two (void *) values. The first (void *) actually points 1039** to a function of type (int (*)(void *)). In order to invoke the connection's 1040** busy-handler, this function should be invoked with the second (void *) in 1041** the array as the only argument. If it returns non-zero, then the operation 1042** should be retried. If it returns zero, the custom VFS should abandon the 1043** current operation. 1044** 1045** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 1046** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 1047** to have SQLite generate a 1048** temporary filename using the same algorithm that is followed to generate 1049** temporary filenames for TEMP tables and other internal uses. The 1050** argument should be a char** which will be filled with the filename 1051** written into memory obtained from [sqlite3_malloc()]. The caller should 1052** invoke [sqlite3_free()] on the result to avoid a memory leak. 1053** 1054** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1055** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1056** maximum number of bytes that will be used for memory-mapped I/O. 1057** The argument is a pointer to a value of type sqlite3_int64 that 1058** is an advisory maximum number of bytes in the file to memory map. The 1059** pointer is overwritten with the old value. The limit is not changed if 1060** the value originally pointed to is negative, and so the current limit 1061** can be queried by passing in a pointer to a negative number. This 1062** file-control is used internally to implement [PRAGMA mmap_size]. 1063** 1064** <li>[[SQLITE_FCNTL_TRACE]] 1065** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1066** to the VFS about what the higher layers of the SQLite stack are doing. 1067** This file control is used by some VFS activity tracing [shims]. 1068** The argument is a zero-terminated string. Higher layers in the 1069** SQLite stack may generate instances of this file control if 1070** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1071** 1072** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1073** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1074** pointer to an integer and it writes a boolean into that integer depending 1075** on whether or not the file has been renamed, moved, or deleted since it 1076** was first opened. 1077** 1078** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1079** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1080** underlying native file handle associated with a file handle. This file 1081** control interprets its argument as a pointer to a native file handle and 1082** writes the resulting value there. 1083** 1084** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1085** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1086** opcode causes the xFileControl method to swap the file handle with the one 1087** pointed to by the pArg argument. This capability is used during testing 1088** and only needs to be supported when SQLITE_TEST is defined. 1089** 1090** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1091** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1092** be advantageous to block on the next WAL lock if the lock is not immediately 1093** available. The WAL subsystem issues this signal during rare 1094** circumstances in order to fix a problem with priority inversion. 1095** Applications should <em>not</em> use this file-control. 1096** 1097** <li>[[SQLITE_FCNTL_ZIPVFS]] 1098** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1099** VFS should return SQLITE_NOTFOUND for this opcode. 1100** 1101** <li>[[SQLITE_FCNTL_RBU]] 1102** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1103** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1104** this opcode. 1105** 1106** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1107** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1108** the file descriptor is placed in "batch write mode", which 1109** means all subsequent write operations will be deferred and done 1110** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1111** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1112** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1113** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1114** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1115** no VFS interface calls on the same [sqlite3_file] file descriptor 1116** except for calls to the xWrite method and the xFileControl method 1117** with [SQLITE_FCNTL_SIZE_HINT]. 1118** 1119** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1120** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1121** operations since the previous successful call to 1122** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1123** This file control returns [SQLITE_OK] if and only if the writes were 1124** all performed successfully and have been committed to persistent storage. 1125** ^Regardless of whether or not it is successful, this file control takes 1126** the file descriptor out of batch write mode so that all subsequent 1127** write operations are independent. 1128** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1129** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1130** 1131** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1132** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1133** operations since the previous successful call to 1134** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1135** ^This file control takes the file descriptor out of batch write mode 1136** so that all subsequent write operations are independent. 1137** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1138** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1139** 1140** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1141** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1142** to block for up to M milliseconds before failing when attempting to 1143** obtain a file lock using the xLock or xShmLock methods of the VFS. 1144** The parameter is a pointer to a 32-bit signed integer that contains 1145** the value that M is to be set to. Before returning, the 32-bit signed 1146** integer is overwritten with the previous value of M. 1147** 1148** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1149** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1150** a database file. The argument is a pointer to a 32-bit unsigned integer. 1151** The "data version" for the pager is written into the pointer. The 1152** "data version" changes whenever any change occurs to the corresponding 1153** database file, either through SQL statements on the same database 1154** connection or through transactions committed by separate database 1155** connections possibly in other processes. The [sqlite3_total_changes()] 1156** interface can be used to find if any database on the connection has changed, 1157** but that interface responds to changes on TEMP as well as MAIN and does 1158** not provide a mechanism to detect changes to MAIN only. Also, the 1159** [sqlite3_total_changes()] interface responds to internal changes only and 1160** omits changes made by other database connections. The 1161** [PRAGMA data_version] command provides a mechanism to detect changes to 1162** a single attached database that occur due to other database connections, 1163** but omits changes implemented by the database connection on which it is 1164** called. This file control is the only mechanism to detect changes that 1165** happen either internally or externally and that are associated with 1166** a particular attached database. 1167** 1168** <li>[[SQLITE_FCNTL_CKPT_START]] 1169** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1170** in wal mode before the client starts to copy pages from the wal 1171** file to the database file. 1172** 1173** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1174** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1175** in wal mode after the client has finished copying pages from the wal 1176** file to the database file, but before the *-shm file is updated to 1177** record the fact that the pages have been checkpointed. 1178** </ul> 1179** 1180** <li>[[SQLITE_FCNTL_EXTERNAL_READER]] 1181** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect 1182** whether or not there is a database client in another process with a wal-mode 1183** transaction open on the database or not. It is only available on unix.The 1184** (void*) argument passed with this file-control should be a pointer to a 1185** value of type (int). The integer value is set to 1 if the database is a wal 1186** mode database and there exists at least one client in another process that 1187** currently has an SQL transaction open on the database. It is set to 0 if 1188** the database is not a wal-mode db, or if there is no such connection in any 1189** other process. This opcode cannot be used to detect transactions opened 1190** by clients within the current process, only within other processes. 1191** </ul> 1192** 1193** <li>[[SQLITE_FCNTL_CKSM_FILE]] 1194** Used by the cksmvfs VFS module only. 1195** </ul> 1196*/ 1197#define SQLITE_FCNTL_LOCKSTATE 1 1198#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1199#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1200#define SQLITE_FCNTL_LAST_ERRNO 4 1201#define SQLITE_FCNTL_SIZE_HINT 5 1202#define SQLITE_FCNTL_CHUNK_SIZE 6 1203#define SQLITE_FCNTL_FILE_POINTER 7 1204#define SQLITE_FCNTL_SYNC_OMITTED 8 1205#define SQLITE_FCNTL_WIN32_AV_RETRY 9 1206#define SQLITE_FCNTL_PERSIST_WAL 10 1207#define SQLITE_FCNTL_OVERWRITE 11 1208#define SQLITE_FCNTL_VFSNAME 12 1209#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1210#define SQLITE_FCNTL_PRAGMA 14 1211#define SQLITE_FCNTL_BUSYHANDLER 15 1212#define SQLITE_FCNTL_TEMPFILENAME 16 1213#define SQLITE_FCNTL_MMAP_SIZE 18 1214#define SQLITE_FCNTL_TRACE 19 1215#define SQLITE_FCNTL_HAS_MOVED 20 1216#define SQLITE_FCNTL_SYNC 21 1217#define SQLITE_FCNTL_COMMIT_PHASETWO 22 1218#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1219#define SQLITE_FCNTL_WAL_BLOCK 24 1220#define SQLITE_FCNTL_ZIPVFS 25 1221#define SQLITE_FCNTL_RBU 26 1222#define SQLITE_FCNTL_VFS_POINTER 27 1223#define SQLITE_FCNTL_JOURNAL_POINTER 28 1224#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1225#define SQLITE_FCNTL_PDB 30 1226#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1227#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1228#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1229#define SQLITE_FCNTL_LOCK_TIMEOUT 34 1230#define SQLITE_FCNTL_DATA_VERSION 35 1231#define SQLITE_FCNTL_SIZE_LIMIT 36 1232#define SQLITE_FCNTL_CKPT_DONE 37 1233#define SQLITE_FCNTL_RESERVE_BYTES 38 1234#define SQLITE_FCNTL_CKPT_START 39 1235#define SQLITE_FCNTL_EXTERNAL_READER 40 1236#define SQLITE_FCNTL_CKSM_FILE 41 1237 1238/* deprecated names */ 1239#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1240#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1241#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1242 1243 1244/* 1245** CAPI3REF: Mutex Handle 1246** 1247** The mutex module within SQLite defines [sqlite3_mutex] to be an 1248** abstract type for a mutex object. The SQLite core never looks 1249** at the internal representation of an [sqlite3_mutex]. It only 1250** deals with pointers to the [sqlite3_mutex] object. 1251** 1252** Mutexes are created using [sqlite3_mutex_alloc()]. 1253*/ 1254typedef struct sqlite3_mutex sqlite3_mutex; 1255 1256/* 1257** CAPI3REF: Loadable Extension Thunk 1258** 1259** A pointer to the opaque sqlite3_api_routines structure is passed as 1260** the third parameter to entry points of [loadable extensions]. This 1261** structure must be typedefed in order to work around compiler warnings 1262** on some platforms. 1263*/ 1264typedef struct sqlite3_api_routines sqlite3_api_routines; 1265 1266/* 1267** CAPI3REF: File Name 1268** 1269** Type [sqlite3_filename] is used by SQLite to pass filenames to the 1270** xOpen method of a [VFS]. It may be cast to (const char*) and treated 1271** as a normal, nul-terminated, UTF-8 buffer containing the filename, but 1272** may also be passed to special APIs such as: 1273** 1274** <ul> 1275** <li> sqlite3_filename_database() 1276** <li> sqlite3_filename_journal() 1277** <li> sqlite3_filename_wal() 1278** <li> sqlite3_uri_parameter() 1279** <li> sqlite3_uri_boolean() 1280** <li> sqlite3_uri_int64() 1281** <li> sqlite3_uri_key() 1282** </ul> 1283*/ 1284typedef const char *sqlite3_filename; 1285 1286/* 1287** CAPI3REF: OS Interface Object 1288** 1289** An instance of the sqlite3_vfs object defines the interface between 1290** the SQLite core and the underlying operating system. The "vfs" 1291** in the name of the object stands for "virtual file system". See 1292** the [VFS | VFS documentation] for further information. 1293** 1294** The VFS interface is sometimes extended by adding new methods onto 1295** the end. Each time such an extension occurs, the iVersion field 1296** is incremented. The iVersion value started out as 1 in 1297** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1298** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1299** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1300** may be appended to the sqlite3_vfs object and the iVersion value 1301** may increase again in future versions of SQLite. 1302** Note that due to an oversight, the structure 1303** of the sqlite3_vfs object changed in the transition from 1304** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1305** and yet the iVersion field was not increased. 1306** 1307** The szOsFile field is the size of the subclassed [sqlite3_file] 1308** structure used by this VFS. mxPathname is the maximum length of 1309** a pathname in this VFS. 1310** 1311** Registered sqlite3_vfs objects are kept on a linked list formed by 1312** the pNext pointer. The [sqlite3_vfs_register()] 1313** and [sqlite3_vfs_unregister()] interfaces manage this list 1314** in a thread-safe way. The [sqlite3_vfs_find()] interface 1315** searches the list. Neither the application code nor the VFS 1316** implementation should use the pNext pointer. 1317** 1318** The pNext field is the only field in the sqlite3_vfs 1319** structure that SQLite will ever modify. SQLite will only access 1320** or modify this field while holding a particular static mutex. 1321** The application should never modify anything within the sqlite3_vfs 1322** object once the object has been registered. 1323** 1324** The zName field holds the name of the VFS module. The name must 1325** be unique across all VFS modules. 1326** 1327** [[sqlite3_vfs.xOpen]] 1328** ^SQLite guarantees that the zFilename parameter to xOpen 1329** is either a NULL pointer or string obtained 1330** from xFullPathname() with an optional suffix added. 1331** ^If a suffix is added to the zFilename parameter, it will 1332** consist of a single "-" character followed by no more than 1333** 11 alphanumeric and/or "-" characters. 1334** ^SQLite further guarantees that 1335** the string will be valid and unchanged until xClose() is 1336** called. Because of the previous sentence, 1337** the [sqlite3_file] can safely store a pointer to the 1338** filename if it needs to remember the filename for some reason. 1339** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1340** must invent its own temporary name for the file. ^Whenever the 1341** xFilename parameter is NULL it will also be the case that the 1342** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1343** 1344** The flags argument to xOpen() includes all bits set in 1345** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1346** or [sqlite3_open16()] is used, then flags includes at least 1347** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1348** If xOpen() opens a file read-only then it sets *pOutFlags to 1349** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1350** 1351** ^(SQLite will also add one of the following flags to the xOpen() 1352** call, depending on the object being opened: 1353** 1354** <ul> 1355** <li> [SQLITE_OPEN_MAIN_DB] 1356** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1357** <li> [SQLITE_OPEN_TEMP_DB] 1358** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1359** <li> [SQLITE_OPEN_TRANSIENT_DB] 1360** <li> [SQLITE_OPEN_SUBJOURNAL] 1361** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1362** <li> [SQLITE_OPEN_WAL] 1363** </ul>)^ 1364** 1365** The file I/O implementation can use the object type flags to 1366** change the way it deals with files. For example, an application 1367** that does not care about crash recovery or rollback might make 1368** the open of a journal file a no-op. Writes to this journal would 1369** also be no-ops, and any attempt to read the journal would return 1370** SQLITE_IOERR. Or the implementation might recognize that a database 1371** file will be doing page-aligned sector reads and writes in a random 1372** order and set up its I/O subsystem accordingly. 1373** 1374** SQLite might also add one of the following flags to the xOpen method: 1375** 1376** <ul> 1377** <li> [SQLITE_OPEN_DELETEONCLOSE] 1378** <li> [SQLITE_OPEN_EXCLUSIVE] 1379** </ul> 1380** 1381** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1382** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1383** will be set for TEMP databases and their journals, transient 1384** databases, and subjournals. 1385** 1386** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1387** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1388** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1389** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1390** SQLITE_OPEN_CREATE, is used to indicate that file should always 1391** be created, and that it is an error if it already exists. 1392** It is <i>not</i> used to indicate the file should be opened 1393** for exclusive access. 1394** 1395** ^At least szOsFile bytes of memory are allocated by SQLite 1396** to hold the [sqlite3_file] structure passed as the third 1397** argument to xOpen. The xOpen method does not have to 1398** allocate the structure; it should just fill it in. Note that 1399** the xOpen method must set the sqlite3_file.pMethods to either 1400** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1401** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1402** element will be valid after xOpen returns regardless of the success 1403** or failure of the xOpen call. 1404** 1405** [[sqlite3_vfs.xAccess]] 1406** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1407** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1408** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1409** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1410** flag is never actually used and is not implemented in the built-in 1411** VFSes of SQLite. The file is named by the second argument and can be a 1412** directory. The xAccess method returns [SQLITE_OK] on success or some 1413** non-zero error code if there is an I/O error or if the name of 1414** the file given in the second argument is illegal. If SQLITE_OK 1415** is returned, then non-zero or zero is written into *pResOut to indicate 1416** whether or not the file is accessible. 1417** 1418** ^SQLite will always allocate at least mxPathname+1 bytes for the 1419** output buffer xFullPathname. The exact size of the output buffer 1420** is also passed as a parameter to both methods. If the output buffer 1421** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1422** handled as a fatal error by SQLite, vfs implementations should endeavor 1423** to prevent this by setting mxPathname to a sufficiently large value. 1424** 1425** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1426** interfaces are not strictly a part of the filesystem, but they are 1427** included in the VFS structure for completeness. 1428** The xRandomness() function attempts to return nBytes bytes 1429** of good-quality randomness into zOut. The return value is 1430** the actual number of bytes of randomness obtained. 1431** The xSleep() method causes the calling thread to sleep for at 1432** least the number of microseconds given. ^The xCurrentTime() 1433** method returns a Julian Day Number for the current date and time as 1434** a floating point value. 1435** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1436** Day Number multiplied by 86400000 (the number of milliseconds in 1437** a 24-hour day). 1438** ^SQLite will use the xCurrentTimeInt64() method to get the current 1439** date and time if that method is available (if iVersion is 2 or 1440** greater and the function pointer is not NULL) and will fall back 1441** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1442** 1443** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1444** are not used by the SQLite core. These optional interfaces are provided 1445** by some VFSes to facilitate testing of the VFS code. By overriding 1446** system calls with functions under its control, a test program can 1447** simulate faults and error conditions that would otherwise be difficult 1448** or impossible to induce. The set of system calls that can be overridden 1449** varies from one VFS to another, and from one version of the same VFS to the 1450** next. Applications that use these interfaces must be prepared for any 1451** or all of these interfaces to be NULL or for their behavior to change 1452** from one release to the next. Applications must not attempt to access 1453** any of these methods if the iVersion of the VFS is less than 3. 1454*/ 1455typedef struct sqlite3_vfs sqlite3_vfs; 1456typedef void (*sqlite3_syscall_ptr)(void); 1457struct sqlite3_vfs { 1458 int iVersion; /* Structure version number (currently 3) */ 1459 int szOsFile; /* Size of subclassed sqlite3_file */ 1460 int mxPathname; /* Maximum file pathname length */ 1461 sqlite3_vfs *pNext; /* Next registered VFS */ 1462 const char *zName; /* Name of this virtual file system */ 1463 void *pAppData; /* Pointer to application-specific data */ 1464 int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*, 1465 int flags, int *pOutFlags); 1466 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1467 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1468 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1469 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1470 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1471 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1472 void (*xDlClose)(sqlite3_vfs*, void*); 1473 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1474 int (*xSleep)(sqlite3_vfs*, int microseconds); 1475 int (*xCurrentTime)(sqlite3_vfs*, double*); 1476 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1477 /* 1478 ** The methods above are in version 1 of the sqlite_vfs object 1479 ** definition. Those that follow are added in version 2 or later 1480 */ 1481 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1482 /* 1483 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1484 ** Those below are for version 3 and greater. 1485 */ 1486 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1487 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1488 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1489 /* 1490 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1491 ** New fields may be appended in future versions. The iVersion 1492 ** value will increment whenever this happens. 1493 */ 1494}; 1495 1496/* 1497** CAPI3REF: Flags for the xAccess VFS method 1498** 1499** These integer constants can be used as the third parameter to 1500** the xAccess method of an [sqlite3_vfs] object. They determine 1501** what kind of permissions the xAccess method is looking for. 1502** With SQLITE_ACCESS_EXISTS, the xAccess method 1503** simply checks whether the file exists. 1504** With SQLITE_ACCESS_READWRITE, the xAccess method 1505** checks whether the named directory is both readable and writable 1506** (in other words, if files can be added, removed, and renamed within 1507** the directory). 1508** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1509** [temp_store_directory pragma], though this could change in a future 1510** release of SQLite. 1511** With SQLITE_ACCESS_READ, the xAccess method 1512** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1513** currently unused, though it might be used in a future release of 1514** SQLite. 1515*/ 1516#define SQLITE_ACCESS_EXISTS 0 1517#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1518#define SQLITE_ACCESS_READ 2 /* Unused */ 1519 1520/* 1521** CAPI3REF: Flags for the xShmLock VFS method 1522** 1523** These integer constants define the various locking operations 1524** allowed by the xShmLock method of [sqlite3_io_methods]. The 1525** following are the only legal combinations of flags to the 1526** xShmLock method: 1527** 1528** <ul> 1529** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1530** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1531** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1532** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1533** </ul> 1534** 1535** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1536** was given on the corresponding lock. 1537** 1538** The xShmLock method can transition between unlocked and SHARED or 1539** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1540** and EXCLUSIVE. 1541*/ 1542#define SQLITE_SHM_UNLOCK 1 1543#define SQLITE_SHM_LOCK 2 1544#define SQLITE_SHM_SHARED 4 1545#define SQLITE_SHM_EXCLUSIVE 8 1546 1547/* 1548** CAPI3REF: Maximum xShmLock index 1549** 1550** The xShmLock method on [sqlite3_io_methods] may use values 1551** between 0 and this upper bound as its "offset" argument. 1552** The SQLite core will never attempt to acquire or release a 1553** lock outside of this range 1554*/ 1555#define SQLITE_SHM_NLOCK 8 1556 1557 1558/* 1559** CAPI3REF: Initialize The SQLite Library 1560** 1561** ^The sqlite3_initialize() routine initializes the 1562** SQLite library. ^The sqlite3_shutdown() routine 1563** deallocates any resources that were allocated by sqlite3_initialize(). 1564** These routines are designed to aid in process initialization and 1565** shutdown on embedded systems. Workstation applications using 1566** SQLite normally do not need to invoke either of these routines. 1567** 1568** A call to sqlite3_initialize() is an "effective" call if it is 1569** the first time sqlite3_initialize() is invoked during the lifetime of 1570** the process, or if it is the first time sqlite3_initialize() is invoked 1571** following a call to sqlite3_shutdown(). ^(Only an effective call 1572** of sqlite3_initialize() does any initialization. All other calls 1573** are harmless no-ops.)^ 1574** 1575** A call to sqlite3_shutdown() is an "effective" call if it is the first 1576** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1577** an effective call to sqlite3_shutdown() does any deinitialization. 1578** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1579** 1580** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1581** is not. The sqlite3_shutdown() interface must only be called from a 1582** single thread. All open [database connections] must be closed and all 1583** other SQLite resources must be deallocated prior to invoking 1584** sqlite3_shutdown(). 1585** 1586** Among other things, ^sqlite3_initialize() will invoke 1587** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1588** will invoke sqlite3_os_end(). 1589** 1590** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1591** ^If for some reason, sqlite3_initialize() is unable to initialize 1592** the library (perhaps it is unable to allocate a needed resource such 1593** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1594** 1595** ^The sqlite3_initialize() routine is called internally by many other 1596** SQLite interfaces so that an application usually does not need to 1597** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1598** calls sqlite3_initialize() so the SQLite library will be automatically 1599** initialized when [sqlite3_open()] is called if it has not be initialized 1600** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1601** compile-time option, then the automatic calls to sqlite3_initialize() 1602** are omitted and the application must call sqlite3_initialize() directly 1603** prior to using any other SQLite interface. For maximum portability, 1604** it is recommended that applications always invoke sqlite3_initialize() 1605** directly prior to using any other SQLite interface. Future releases 1606** of SQLite may require this. In other words, the behavior exhibited 1607** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1608** default behavior in some future release of SQLite. 1609** 1610** The sqlite3_os_init() routine does operating-system specific 1611** initialization of the SQLite library. The sqlite3_os_end() 1612** routine undoes the effect of sqlite3_os_init(). Typical tasks 1613** performed by these routines include allocation or deallocation 1614** of static resources, initialization of global variables, 1615** setting up a default [sqlite3_vfs] module, or setting up 1616** a default configuration using [sqlite3_config()]. 1617** 1618** The application should never invoke either sqlite3_os_init() 1619** or sqlite3_os_end() directly. The application should only invoke 1620** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1621** interface is called automatically by sqlite3_initialize() and 1622** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1623** implementations for sqlite3_os_init() and sqlite3_os_end() 1624** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1625** When [custom builds | built for other platforms] 1626** (using the [SQLITE_OS_OTHER=1] compile-time 1627** option) the application must supply a suitable implementation for 1628** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1629** implementation of sqlite3_os_init() or sqlite3_os_end() 1630** must return [SQLITE_OK] on success and some other [error code] upon 1631** failure. 1632*/ 1633int sqlite3_initialize(void); 1634int sqlite3_shutdown(void); 1635int sqlite3_os_init(void); 1636int sqlite3_os_end(void); 1637 1638/* 1639** CAPI3REF: Configuring The SQLite Library 1640** 1641** The sqlite3_config() interface is used to make global configuration 1642** changes to SQLite in order to tune SQLite to the specific needs of 1643** the application. The default configuration is recommended for most 1644** applications and so this routine is usually not necessary. It is 1645** provided to support rare applications with unusual needs. 1646** 1647** <b>The sqlite3_config() interface is not threadsafe. The application 1648** must ensure that no other SQLite interfaces are invoked by other 1649** threads while sqlite3_config() is running.</b> 1650** 1651** The sqlite3_config() interface 1652** may only be invoked prior to library initialization using 1653** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1654** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1655** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1656** Note, however, that ^sqlite3_config() can be called as part of the 1657** implementation of an application-defined [sqlite3_os_init()]. 1658** 1659** The first argument to sqlite3_config() is an integer 1660** [configuration option] that determines 1661** what property of SQLite is to be configured. Subsequent arguments 1662** vary depending on the [configuration option] 1663** in the first argument. 1664** 1665** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1666** ^If the option is unknown or SQLite is unable to set the option 1667** then this routine returns a non-zero [error code]. 1668*/ 1669int sqlite3_config(int, ...); 1670 1671/* 1672** CAPI3REF: Configure database connections 1673** METHOD: sqlite3 1674** 1675** The sqlite3_db_config() interface is used to make configuration 1676** changes to a [database connection]. The interface is similar to 1677** [sqlite3_config()] except that the changes apply to a single 1678** [database connection] (specified in the first argument). 1679** 1680** The second argument to sqlite3_db_config(D,V,...) is the 1681** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1682** that indicates what aspect of the [database connection] is being configured. 1683** Subsequent arguments vary depending on the configuration verb. 1684** 1685** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1686** the call is considered successful. 1687*/ 1688int sqlite3_db_config(sqlite3*, int op, ...); 1689 1690/* 1691** CAPI3REF: Memory Allocation Routines 1692** 1693** An instance of this object defines the interface between SQLite 1694** and low-level memory allocation routines. 1695** 1696** This object is used in only one place in the SQLite interface. 1697** A pointer to an instance of this object is the argument to 1698** [sqlite3_config()] when the configuration option is 1699** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1700** By creating an instance of this object 1701** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1702** during configuration, an application can specify an alternative 1703** memory allocation subsystem for SQLite to use for all of its 1704** dynamic memory needs. 1705** 1706** Note that SQLite comes with several [built-in memory allocators] 1707** that are perfectly adequate for the overwhelming majority of applications 1708** and that this object is only useful to a tiny minority of applications 1709** with specialized memory allocation requirements. This object is 1710** also used during testing of SQLite in order to specify an alternative 1711** memory allocator that simulates memory out-of-memory conditions in 1712** order to verify that SQLite recovers gracefully from such 1713** conditions. 1714** 1715** The xMalloc, xRealloc, and xFree methods must work like the 1716** malloc(), realloc() and free() functions from the standard C library. 1717** ^SQLite guarantees that the second argument to 1718** xRealloc is always a value returned by a prior call to xRoundup. 1719** 1720** xSize should return the allocated size of a memory allocation 1721** previously obtained from xMalloc or xRealloc. The allocated size 1722** is always at least as big as the requested size but may be larger. 1723** 1724** The xRoundup method returns what would be the allocated size of 1725** a memory allocation given a particular requested size. Most memory 1726** allocators round up memory allocations at least to the next multiple 1727** of 8. Some allocators round up to a larger multiple or to a power of 2. 1728** Every memory allocation request coming in through [sqlite3_malloc()] 1729** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1730** that causes the corresponding memory allocation to fail. 1731** 1732** The xInit method initializes the memory allocator. For example, 1733** it might allocate any required mutexes or initialize internal data 1734** structures. The xShutdown method is invoked (indirectly) by 1735** [sqlite3_shutdown()] and should deallocate any resources acquired 1736** by xInit. The pAppData pointer is used as the only parameter to 1737** xInit and xShutdown. 1738** 1739** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1740** the xInit method, so the xInit method need not be threadsafe. The 1741** xShutdown method is only called from [sqlite3_shutdown()] so it does 1742** not need to be threadsafe either. For all other methods, SQLite 1743** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1744** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1745** it is by default) and so the methods are automatically serialized. 1746** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1747** methods must be threadsafe or else make their own arrangements for 1748** serialization. 1749** 1750** SQLite will never invoke xInit() more than once without an intervening 1751** call to xShutdown(). 1752*/ 1753typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1754struct sqlite3_mem_methods { 1755 void *(*xMalloc)(int); /* Memory allocation function */ 1756 void (*xFree)(void*); /* Free a prior allocation */ 1757 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1758 int (*xSize)(void*); /* Return the size of an allocation */ 1759 int (*xRoundup)(int); /* Round up request size to allocation size */ 1760 int (*xInit)(void*); /* Initialize the memory allocator */ 1761 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1762 void *pAppData; /* Argument to xInit() and xShutdown() */ 1763}; 1764 1765/* 1766** CAPI3REF: Configuration Options 1767** KEYWORDS: {configuration option} 1768** 1769** These constants are the available integer configuration options that 1770** can be passed as the first argument to the [sqlite3_config()] interface. 1771** 1772** New configuration options may be added in future releases of SQLite. 1773** Existing configuration options might be discontinued. Applications 1774** should check the return code from [sqlite3_config()] to make sure that 1775** the call worked. The [sqlite3_config()] interface will return a 1776** non-zero [error code] if a discontinued or unsupported configuration option 1777** is invoked. 1778** 1779** <dl> 1780** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1781** <dd>There are no arguments to this option. ^This option sets the 1782** [threading mode] to Single-thread. In other words, it disables 1783** all mutexing and puts SQLite into a mode where it can only be used 1784** by a single thread. ^If SQLite is compiled with 1785** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1786** it is not possible to change the [threading mode] from its default 1787** value of Single-thread and so [sqlite3_config()] will return 1788** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1789** configuration option.</dd> 1790** 1791** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1792** <dd>There are no arguments to this option. ^This option sets the 1793** [threading mode] to Multi-thread. In other words, it disables 1794** mutexing on [database connection] and [prepared statement] objects. 1795** The application is responsible for serializing access to 1796** [database connections] and [prepared statements]. But other mutexes 1797** are enabled so that SQLite will be safe to use in a multi-threaded 1798** environment as long as no two threads attempt to use the same 1799** [database connection] at the same time. ^If SQLite is compiled with 1800** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1801** it is not possible to set the Multi-thread [threading mode] and 1802** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1803** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1804** 1805** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1806** <dd>There are no arguments to this option. ^This option sets the 1807** [threading mode] to Serialized. In other words, this option enables 1808** all mutexes including the recursive 1809** mutexes on [database connection] and [prepared statement] objects. 1810** In this mode (which is the default when SQLite is compiled with 1811** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1812** to [database connections] and [prepared statements] so that the 1813** application is free to use the same [database connection] or the 1814** same [prepared statement] in different threads at the same time. 1815** ^If SQLite is compiled with 1816** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1817** it is not possible to set the Serialized [threading mode] and 1818** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1819** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1820** 1821** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1822** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1823** a pointer to an instance of the [sqlite3_mem_methods] structure. 1824** The argument specifies 1825** alternative low-level memory allocation routines to be used in place of 1826** the memory allocation routines built into SQLite.)^ ^SQLite makes 1827** its own private copy of the content of the [sqlite3_mem_methods] structure 1828** before the [sqlite3_config()] call returns.</dd> 1829** 1830** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1831** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1832** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1833** The [sqlite3_mem_methods] 1834** structure is filled with the currently defined memory allocation routines.)^ 1835** This option can be used to overload the default memory allocation 1836** routines with a wrapper that simulations memory allocation failure or 1837** tracks memory usage, for example. </dd> 1838** 1839** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1840** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1841** type int, interpreted as a boolean, which if true provides a hint to 1842** SQLite that it should avoid large memory allocations if possible. 1843** SQLite will run faster if it is free to make large memory allocations, 1844** but some application might prefer to run slower in exchange for 1845** guarantees about memory fragmentation that are possible if large 1846** allocations are avoided. This hint is normally off. 1847** </dd> 1848** 1849** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1850** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1851** interpreted as a boolean, which enables or disables the collection of 1852** memory allocation statistics. ^(When memory allocation statistics are 1853** disabled, the following SQLite interfaces become non-operational: 1854** <ul> 1855** <li> [sqlite3_hard_heap_limit64()] 1856** <li> [sqlite3_memory_used()] 1857** <li> [sqlite3_memory_highwater()] 1858** <li> [sqlite3_soft_heap_limit64()] 1859** <li> [sqlite3_status64()] 1860** </ul>)^ 1861** ^Memory allocation statistics are enabled by default unless SQLite is 1862** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1863** allocation statistics are disabled by default. 1864** </dd> 1865** 1866** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1867** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1868** </dd> 1869** 1870** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1871** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1872** that SQLite can use for the database page cache with the default page 1873** cache implementation. 1874** This configuration option is a no-op if an application-defined page 1875** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1876** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1877** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1878** and the number of cache lines (N). 1879** The sz argument should be the size of the largest database page 1880** (a power of two between 512 and 65536) plus some extra bytes for each 1881** page header. ^The number of extra bytes needed by the page header 1882** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1883** ^It is harmless, apart from the wasted memory, 1884** for the sz parameter to be larger than necessary. The pMem 1885** argument must be either a NULL pointer or a pointer to an 8-byte 1886** aligned block of memory of at least sz*N bytes, otherwise 1887** subsequent behavior is undefined. 1888** ^When pMem is not NULL, SQLite will strive to use the memory provided 1889** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1890** a page cache line is larger than sz bytes or if all of the pMem buffer 1891** is exhausted. 1892** ^If pMem is NULL and N is non-zero, then each database connection 1893** does an initial bulk allocation for page cache memory 1894** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1895** of -1024*N bytes if N is negative, . ^If additional 1896** page cache memory is needed beyond what is provided by the initial 1897** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1898** additional cache line. </dd> 1899** 1900** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1901** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1902** that SQLite will use for all of its dynamic memory allocation needs 1903** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1904** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1905** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1906** [SQLITE_ERROR] if invoked otherwise. 1907** ^There are three arguments to SQLITE_CONFIG_HEAP: 1908** An 8-byte aligned pointer to the memory, 1909** the number of bytes in the memory buffer, and the minimum allocation size. 1910** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1911** to using its default memory allocator (the system malloc() implementation), 1912** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1913** memory pointer is not NULL then the alternative memory 1914** allocator is engaged to handle all of SQLites memory allocation needs. 1915** The first pointer (the memory pointer) must be aligned to an 8-byte 1916** boundary or subsequent behavior of SQLite will be undefined. 1917** The minimum allocation size is capped at 2**12. Reasonable values 1918** for the minimum allocation size are 2**5 through 2**8.</dd> 1919** 1920** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1921** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1922** pointer to an instance of the [sqlite3_mutex_methods] structure. 1923** The argument specifies alternative low-level mutex routines to be used 1924** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1925** the content of the [sqlite3_mutex_methods] structure before the call to 1926** [sqlite3_config()] returns. ^If SQLite is compiled with 1927** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1928** the entire mutexing subsystem is omitted from the build and hence calls to 1929** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1930** return [SQLITE_ERROR].</dd> 1931** 1932** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1933** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1934** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1935** [sqlite3_mutex_methods] 1936** structure is filled with the currently defined mutex routines.)^ 1937** This option can be used to overload the default mutex allocation 1938** routines with a wrapper used to track mutex usage for performance 1939** profiling or testing, for example. ^If SQLite is compiled with 1940** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1941** the entire mutexing subsystem is omitted from the build and hence calls to 1942** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1943** return [SQLITE_ERROR].</dd> 1944** 1945** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1946** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1947** the default size of lookaside memory on each [database connection]. 1948** The first argument is the 1949** size of each lookaside buffer slot and the second is the number of 1950** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1951** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1952** option to [sqlite3_db_config()] can be used to change the lookaside 1953** configuration on individual connections.)^ </dd> 1954** 1955** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1956** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1957** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1958** the interface to a custom page cache implementation.)^ 1959** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1960** 1961** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1962** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1963** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1964** the current page cache implementation into that object.)^ </dd> 1965** 1966** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1967** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1968** global [error log]. 1969** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1970** function with a call signature of void(*)(void*,int,const char*), 1971** and a pointer to void. ^If the function pointer is not NULL, it is 1972** invoked by [sqlite3_log()] to process each logging event. ^If the 1973** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1974** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1975** passed through as the first parameter to the application-defined logger 1976** function whenever that function is invoked. ^The second parameter to 1977** the logger function is a copy of the first parameter to the corresponding 1978** [sqlite3_log()] call and is intended to be a [result code] or an 1979** [extended result code]. ^The third parameter passed to the logger is 1980** log message after formatting via [sqlite3_snprintf()]. 1981** The SQLite logging interface is not reentrant; the logger function 1982** supplied by the application must not invoke any SQLite interface. 1983** In a multi-threaded application, the application-defined logger 1984** function must be threadsafe. </dd> 1985** 1986** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1987** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1988** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1989** then URI handling is globally disabled.)^ ^If URI handling is globally 1990** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1991** [sqlite3_open16()] or 1992** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1993** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1994** connection is opened. ^If it is globally disabled, filenames are 1995** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1996** database connection is opened. ^(By default, URI handling is globally 1997** disabled. The default value may be changed by compiling with the 1998** [SQLITE_USE_URI] symbol defined.)^ 1999** 2000** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 2001** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 2002** argument which is interpreted as a boolean in order to enable or disable 2003** the use of covering indices for full table scans in the query optimizer. 2004** ^The default setting is determined 2005** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 2006** if that compile-time option is omitted. 2007** The ability to disable the use of covering indices for full table scans 2008** is because some incorrectly coded legacy applications might malfunction 2009** when the optimization is enabled. Providing the ability to 2010** disable the optimization allows the older, buggy application code to work 2011** without change even with newer versions of SQLite. 2012** 2013** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 2014** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 2015** <dd> These options are obsolete and should not be used by new code. 2016** They are retained for backwards compatibility but are now no-ops. 2017** </dd> 2018** 2019** [[SQLITE_CONFIG_SQLLOG]] 2020** <dt>SQLITE_CONFIG_SQLLOG 2021** <dd>This option is only available if sqlite is compiled with the 2022** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 2023** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 2024** The second should be of type (void*). The callback is invoked by the library 2025** in three separate circumstances, identified by the value passed as the 2026** fourth parameter. If the fourth parameter is 0, then the database connection 2027** passed as the second argument has just been opened. The third argument 2028** points to a buffer containing the name of the main database file. If the 2029** fourth parameter is 1, then the SQL statement that the third parameter 2030** points to has just been executed. Or, if the fourth parameter is 2, then 2031** the connection being passed as the second parameter is being closed. The 2032** third parameter is passed NULL In this case. An example of using this 2033** configuration option can be seen in the "test_sqllog.c" source file in 2034** the canonical SQLite source tree.</dd> 2035** 2036** [[SQLITE_CONFIG_MMAP_SIZE]] 2037** <dt>SQLITE_CONFIG_MMAP_SIZE 2038** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 2039** that are the default mmap size limit (the default setting for 2040** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 2041** ^The default setting can be overridden by each database connection using 2042** either the [PRAGMA mmap_size] command, or by using the 2043** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 2044** will be silently truncated if necessary so that it does not exceed the 2045** compile-time maximum mmap size set by the 2046** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 2047** ^If either argument to this option is negative, then that argument is 2048** changed to its compile-time default. 2049** 2050** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 2051** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 2052** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 2053** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 2054** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 2055** that specifies the maximum size of the created heap. 2056** 2057** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 2058** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 2059** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 2060** is a pointer to an integer and writes into that integer the number of extra 2061** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 2062** The amount of extra space required can change depending on the compiler, 2063** target platform, and SQLite version. 2064** 2065** [[SQLITE_CONFIG_PMASZ]] 2066** <dt>SQLITE_CONFIG_PMASZ 2067** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 2068** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 2069** sorter to that integer. The default minimum PMA Size is set by the 2070** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 2071** to help with sort operations when multithreaded sorting 2072** is enabled (using the [PRAGMA threads] command) and the amount of content 2073** to be sorted exceeds the page size times the minimum of the 2074** [PRAGMA cache_size] setting and this value. 2075** 2076** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 2077** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 2078** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 2079** becomes the [statement journal] spill-to-disk threshold. 2080** [Statement journals] are held in memory until their size (in bytes) 2081** exceeds this threshold, at which point they are written to disk. 2082** Or if the threshold is -1, statement journals are always held 2083** exclusively in memory. 2084** Since many statement journals never become large, setting the spill 2085** threshold to a value such as 64KiB can greatly reduce the amount of 2086** I/O required to support statement rollback. 2087** The default value for this setting is controlled by the 2088** [SQLITE_STMTJRNL_SPILL] compile-time option. 2089** 2090** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2091** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2092** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2093** of type (int) - the new value of the sorter-reference size threshold. 2094** Usually, when SQLite uses an external sort to order records according 2095** to an ORDER BY clause, all fields required by the caller are present in the 2096** sorted records. However, if SQLite determines based on the declared type 2097** of a table column that its values are likely to be very large - larger 2098** than the configured sorter-reference size threshold - then a reference 2099** is stored in each sorted record and the required column values loaded 2100** from the database as records are returned in sorted order. The default 2101** value for this option is to never use this optimization. Specifying a 2102** negative value for this option restores the default behaviour. 2103** This option is only available if SQLite is compiled with the 2104** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2105** 2106** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2107** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2108** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2109** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2110** database created using [sqlite3_deserialize()]. This default maximum 2111** size can be adjusted up or down for individual databases using the 2112** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2113** configuration setting is never used, then the default maximum is determined 2114** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2115** compile-time option is not set, then the default maximum is 1073741824. 2116** </dl> 2117*/ 2118#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2119#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2120#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2121#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2122#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2123#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2124#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2125#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2126#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2127#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2128#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2129/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2130#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2131#define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2132#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2133#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2134#define SQLITE_CONFIG_URI 17 /* int */ 2135#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2136#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2137#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2138#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2139#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2140#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2141#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2142#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2143#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2144#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2145#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2146#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2147 2148/* 2149** CAPI3REF: Database Connection Configuration Options 2150** 2151** These constants are the available integer configuration options that 2152** can be passed as the second argument to the [sqlite3_db_config()] interface. 2153** 2154** New configuration options may be added in future releases of SQLite. 2155** Existing configuration options might be discontinued. Applications 2156** should check the return code from [sqlite3_db_config()] to make sure that 2157** the call worked. ^The [sqlite3_db_config()] interface will return a 2158** non-zero [error code] if a discontinued or unsupported configuration option 2159** is invoked. 2160** 2161** <dl> 2162** [[SQLITE_DBCONFIG_LOOKASIDE]] 2163** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2164** <dd> ^This option takes three additional arguments that determine the 2165** [lookaside memory allocator] configuration for the [database connection]. 2166** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2167** pointer to a memory buffer to use for lookaside memory. 2168** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2169** may be NULL in which case SQLite will allocate the 2170** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2171** size of each lookaside buffer slot. ^The third argument is the number of 2172** slots. The size of the buffer in the first argument must be greater than 2173** or equal to the product of the second and third arguments. The buffer 2174** must be aligned to an 8-byte boundary. ^If the second argument to 2175** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2176** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2177** configuration for a database connection can only be changed when that 2178** connection is not currently using lookaside memory, or in other words 2179** when the "current value" returned by 2180** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 2181** Any attempt to change the lookaside memory configuration when lookaside 2182** memory is in use leaves the configuration unchanged and returns 2183** [SQLITE_BUSY].)^</dd> 2184** 2185** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2186** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2187** <dd> ^This option is used to enable or disable the enforcement of 2188** [foreign key constraints]. There should be two additional arguments. 2189** The first argument is an integer which is 0 to disable FK enforcement, 2190** positive to enable FK enforcement or negative to leave FK enforcement 2191** unchanged. The second parameter is a pointer to an integer into which 2192** is written 0 or 1 to indicate whether FK enforcement is off or on 2193** following this call. The second parameter may be a NULL pointer, in 2194** which case the FK enforcement setting is not reported back. </dd> 2195** 2196** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2197** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2198** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2199** There should be two additional arguments. 2200** The first argument is an integer which is 0 to disable triggers, 2201** positive to enable triggers or negative to leave the setting unchanged. 2202** The second parameter is a pointer to an integer into which 2203** is written 0 or 1 to indicate whether triggers are disabled or enabled 2204** following this call. The second parameter may be a NULL pointer, in 2205** which case the trigger setting is not reported back. 2206** 2207** <p>Originally this option disabled all triggers. ^(However, since 2208** SQLite version 3.35.0, TEMP triggers are still allowed even if 2209** this option is off. So, in other words, this option now only disables 2210** triggers in the main database schema or in the schemas of ATTACH-ed 2211** databases.)^ </dd> 2212** 2213** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2214** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2215** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2216** There should be two additional arguments. 2217** The first argument is an integer which is 0 to disable views, 2218** positive to enable views or negative to leave the setting unchanged. 2219** The second parameter is a pointer to an integer into which 2220** is written 0 or 1 to indicate whether views are disabled or enabled 2221** following this call. The second parameter may be a NULL pointer, in 2222** which case the view setting is not reported back. 2223** 2224** <p>Originally this option disabled all views. ^(However, since 2225** SQLite version 3.35.0, TEMP views are still allowed even if 2226** this option is off. So, in other words, this option now only disables 2227** views in the main database schema or in the schemas of ATTACH-ed 2228** databases.)^ </dd> 2229** 2230** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2231** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2232** <dd> ^This option is used to enable or disable the 2233** [fts3_tokenizer()] function which is part of the 2234** [FTS3] full-text search engine extension. 2235** There should be two additional arguments. 2236** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2237** positive to enable fts3_tokenizer() or negative to leave the setting 2238** unchanged. 2239** The second parameter is a pointer to an integer into which 2240** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2241** following this call. The second parameter may be a NULL pointer, in 2242** which case the new setting is not reported back. </dd> 2243** 2244** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2245** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2246** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2247** interface independently of the [load_extension()] SQL function. 2248** The [sqlite3_enable_load_extension()] API enables or disables both the 2249** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2250** There should be two additional arguments. 2251** When the first argument to this interface is 1, then only the C-API is 2252** enabled and the SQL function remains disabled. If the first argument to 2253** this interface is 0, then both the C-API and the SQL function are disabled. 2254** If the first argument is -1, then no changes are made to state of either the 2255** C-API or the SQL function. 2256** The second parameter is a pointer to an integer into which 2257** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2258** is disabled or enabled following this call. The second parameter may 2259** be a NULL pointer, in which case the new setting is not reported back. 2260** </dd> 2261** 2262** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2263** <dd> ^This option is used to change the name of the "main" database 2264** schema. ^The sole argument is a pointer to a constant UTF8 string 2265** which will become the new schema name in place of "main". ^SQLite 2266** does not make a copy of the new main schema name string, so the application 2267** must ensure that the argument passed into this DBCONFIG option is unchanged 2268** until after the database connection closes. 2269** </dd> 2270** 2271** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2272** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2273** <dd> Usually, when a database in wal mode is closed or detached from a 2274** database handle, SQLite checks if this will mean that there are now no 2275** connections at all to the database. If so, it performs a checkpoint 2276** operation before closing the connection. This option may be used to 2277** override this behaviour. The first parameter passed to this operation 2278** is an integer - positive to disable checkpoints-on-close, or zero (the 2279** default) to enable them, and negative to leave the setting unchanged. 2280** The second parameter is a pointer to an integer 2281** into which is written 0 or 1 to indicate whether checkpoints-on-close 2282** have been disabled - 0 if they are not disabled, 1 if they are. 2283** </dd> 2284** 2285** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2286** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2287** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2288** a single SQL query statement will always use the same algorithm regardless 2289** of values of [bound parameters].)^ The QPSG disables some query optimizations 2290** that look at the values of bound parameters, which can make some queries 2291** slower. But the QPSG has the advantage of more predictable behavior. With 2292** the QPSG active, SQLite will always use the same query plan in the field as 2293** was used during testing in the lab. 2294** The first argument to this setting is an integer which is 0 to disable 2295** the QPSG, positive to enable QPSG, or negative to leave the setting 2296** unchanged. The second parameter is a pointer to an integer into which 2297** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2298** following this call. 2299** </dd> 2300** 2301** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2302** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2303** include output for any operations performed by trigger programs. This 2304** option is used to set or clear (the default) a flag that governs this 2305** behavior. The first parameter passed to this operation is an integer - 2306** positive to enable output for trigger programs, or zero to disable it, 2307** or negative to leave the setting unchanged. 2308** The second parameter is a pointer to an integer into which is written 2309** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2310** it is not disabled, 1 if it is. 2311** </dd> 2312** 2313** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2314** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2315** [VACUUM] in order to reset a database back to an empty database 2316** with no schema and no content. The following process works even for 2317** a badly corrupted database file: 2318** <ol> 2319** <li> If the database connection is newly opened, make sure it has read the 2320** database schema by preparing then discarding some query against the 2321** database, or calling sqlite3_table_column_metadata(), ignoring any 2322** errors. This step is only necessary if the application desires to keep 2323** the database in WAL mode after the reset if it was in WAL mode before 2324** the reset. 2325** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2326** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2327** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2328** </ol> 2329** Because resetting a database is destructive and irreversible, the 2330** process requires the use of this obscure API and multiple steps to help 2331** ensure that it does not happen by accident. 2332** 2333** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2334** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2335** "defensive" flag for a database connection. When the defensive 2336** flag is enabled, language features that allow ordinary SQL to 2337** deliberately corrupt the database file are disabled. The disabled 2338** features include but are not limited to the following: 2339** <ul> 2340** <li> The [PRAGMA writable_schema=ON] statement. 2341** <li> The [PRAGMA journal_mode=OFF] statement. 2342** <li> Writes to the [sqlite_dbpage] virtual table. 2343** <li> Direct writes to [shadow tables]. 2344** </ul> 2345** </dd> 2346** 2347** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2348** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2349** "writable_schema" flag. This has the same effect and is logically equivalent 2350** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2351** The first argument to this setting is an integer which is 0 to disable 2352** the writable_schema, positive to enable writable_schema, or negative to 2353** leave the setting unchanged. The second parameter is a pointer to an 2354** integer into which is written 0 or 1 to indicate whether the writable_schema 2355** is enabled or disabled following this call. 2356** </dd> 2357** 2358** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2359** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2360** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2361** the legacy behavior of the [ALTER TABLE RENAME] command such it 2362** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2363** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2364** additional information. This feature can also be turned on and off 2365** using the [PRAGMA legacy_alter_table] statement. 2366** </dd> 2367** 2368** [[SQLITE_DBCONFIG_DQS_DML]] 2369** <dt>SQLITE_DBCONFIG_DQS_DML</td> 2370** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2371** the legacy [double-quoted string literal] misfeature for DML statements 2372** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2373** default value of this setting is determined by the [-DSQLITE_DQS] 2374** compile-time option. 2375** </dd> 2376** 2377** [[SQLITE_DBCONFIG_DQS_DDL]] 2378** <dt>SQLITE_DBCONFIG_DQS_DDL</td> 2379** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2380** the legacy [double-quoted string literal] misfeature for DDL statements, 2381** such as CREATE TABLE and CREATE INDEX. The 2382** default value of this setting is determined by the [-DSQLITE_DQS] 2383** compile-time option. 2384** </dd> 2385** 2386** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2387** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> 2388** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2389** assume that database schemas are untainted by malicious content. 2390** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2391** takes additional defensive steps to protect the application from harm 2392** including: 2393** <ul> 2394** <li> Prohibit the use of SQL functions inside triggers, views, 2395** CHECK constraints, DEFAULT clauses, expression indexes, 2396** partial indexes, or generated columns 2397** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2398** <li> Prohibit the use of virtual tables inside of triggers or views 2399** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2400** </ul> 2401** This setting defaults to "on" for legacy compatibility, however 2402** all applications are advised to turn it off if possible. This setting 2403** can also be controlled using the [PRAGMA trusted_schema] statement. 2404** </dd> 2405** 2406** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2407** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> 2408** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2409** the legacy file format flag. When activated, this flag causes all newly 2410** created database file to have a schema format version number (the 4-byte 2411** integer found at offset 44 into the database header) of 1. This in turn 2412** means that the resulting database file will be readable and writable by 2413** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2414** newly created databases are generally not understandable by SQLite versions 2415** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2416** is now scarcely any need to generated database files that are compatible 2417** all the way back to version 3.0.0, and so this setting is of little 2418** practical use, but is provided so that SQLite can continue to claim the 2419** ability to generate new database files that are compatible with version 2420** 3.0.0. 2421** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2422** the [VACUUM] command will fail with an obscure error when attempting to 2423** process a table with generated columns and a descending index. This is 2424** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2425** either generated columns or decending indexes. 2426** </dd> 2427** </dl> 2428*/ 2429#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2430#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2431#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2432#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2433#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2434#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2435#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2436#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2437#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2438#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2439#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2440#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2441#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2442#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2443#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2444#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2445#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2446#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2447#define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ 2448 2449/* 2450** CAPI3REF: Enable Or Disable Extended Result Codes 2451** METHOD: sqlite3 2452** 2453** ^The sqlite3_extended_result_codes() routine enables or disables the 2454** [extended result codes] feature of SQLite. ^The extended result 2455** codes are disabled by default for historical compatibility. 2456*/ 2457int sqlite3_extended_result_codes(sqlite3*, int onoff); 2458 2459/* 2460** CAPI3REF: Last Insert Rowid 2461** METHOD: sqlite3 2462** 2463** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2464** has a unique 64-bit signed 2465** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2466** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2467** names are not also used by explicitly declared columns. ^If 2468** the table has a column of type [INTEGER PRIMARY KEY] then that column 2469** is another alias for the rowid. 2470** 2471** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2472** the most recent successful [INSERT] into a rowid table or [virtual table] 2473** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2474** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2475** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2476** zero. 2477** 2478** As well as being set automatically as rows are inserted into database 2479** tables, the value returned by this function may be set explicitly by 2480** [sqlite3_set_last_insert_rowid()] 2481** 2482** Some virtual table implementations may INSERT rows into rowid tables as 2483** part of committing a transaction (e.g. to flush data accumulated in memory 2484** to disk). In this case subsequent calls to this function return the rowid 2485** associated with these internal INSERT operations, which leads to 2486** unintuitive results. Virtual table implementations that do write to rowid 2487** tables in this way can avoid this problem by restoring the original 2488** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2489** control to the user. 2490** 2491** ^(If an [INSERT] occurs within a trigger then this routine will 2492** return the [rowid] of the inserted row as long as the trigger is 2493** running. Once the trigger program ends, the value returned 2494** by this routine reverts to what it was before the trigger was fired.)^ 2495** 2496** ^An [INSERT] that fails due to a constraint violation is not a 2497** successful [INSERT] and does not change the value returned by this 2498** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2499** and INSERT OR ABORT make no changes to the return value of this 2500** routine when their insertion fails. ^(When INSERT OR REPLACE 2501** encounters a constraint violation, it does not fail. The 2502** INSERT continues to completion after deleting rows that caused 2503** the constraint problem so INSERT OR REPLACE will always change 2504** the return value of this interface.)^ 2505** 2506** ^For the purposes of this routine, an [INSERT] is considered to 2507** be successful even if it is subsequently rolled back. 2508** 2509** This function is accessible to SQL statements via the 2510** [last_insert_rowid() SQL function]. 2511** 2512** If a separate thread performs a new [INSERT] on the same 2513** database connection while the [sqlite3_last_insert_rowid()] 2514** function is running and thus changes the last insert [rowid], 2515** then the value returned by [sqlite3_last_insert_rowid()] is 2516** unpredictable and might not equal either the old or the new 2517** last insert [rowid]. 2518*/ 2519sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2520 2521/* 2522** CAPI3REF: Set the Last Insert Rowid value. 2523** METHOD: sqlite3 2524** 2525** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2526** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2527** without inserting a row into the database. 2528*/ 2529void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2530 2531/* 2532** CAPI3REF: Count The Number Of Rows Modified 2533** METHOD: sqlite3 2534** 2535** ^These functions return the number of rows modified, inserted or 2536** deleted by the most recently completed INSERT, UPDATE or DELETE 2537** statement on the database connection specified by the only parameter. 2538** The two functions are identical except for the type of the return value 2539** and that if the number of rows modified by the most recent INSERT, UPDATE 2540** or DELETE is greater than the maximum value supported by type "int", then 2541** the return value of sqlite3_changes() is undefined. ^Executing any other 2542** type of SQL statement does not modify the value returned by these functions. 2543** 2544** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2545** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2546** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2547** 2548** Changes to a view that are intercepted by 2549** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2550** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2551** DELETE statement run on a view is always zero. Only changes made to real 2552** tables are counted. 2553** 2554** Things are more complicated if the sqlite3_changes() function is 2555** executed while a trigger program is running. This may happen if the 2556** program uses the [changes() SQL function], or if some other callback 2557** function invokes sqlite3_changes() directly. Essentially: 2558** 2559** <ul> 2560** <li> ^(Before entering a trigger program the value returned by 2561** sqlite3_changes() function is saved. After the trigger program 2562** has finished, the original value is restored.)^ 2563** 2564** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2565** statement sets the value returned by sqlite3_changes() 2566** upon completion as normal. Of course, this value will not include 2567** any changes performed by sub-triggers, as the sqlite3_changes() 2568** value will be saved and restored after each sub-trigger has run.)^ 2569** </ul> 2570** 2571** ^This means that if the changes() SQL function (or similar) is used 2572** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2573** returns the value as set when the calling statement began executing. 2574** ^If it is used by the second or subsequent such statement within a trigger 2575** program, the value returned reflects the number of rows modified by the 2576** previous INSERT, UPDATE or DELETE statement within the same trigger. 2577** 2578** If a separate thread makes changes on the same database connection 2579** while [sqlite3_changes()] is running then the value returned 2580** is unpredictable and not meaningful. 2581** 2582** See also: 2583** <ul> 2584** <li> the [sqlite3_total_changes()] interface 2585** <li> the [count_changes pragma] 2586** <li> the [changes() SQL function] 2587** <li> the [data_version pragma] 2588** </ul> 2589*/ 2590int sqlite3_changes(sqlite3*); 2591sqlite3_int64 sqlite3_changes64(sqlite3*); 2592 2593/* 2594** CAPI3REF: Total Number Of Rows Modified 2595** METHOD: sqlite3 2596** 2597** ^These functions return the total number of rows inserted, modified or 2598** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2599** since the database connection was opened, including those executed as 2600** part of trigger programs. The two functions are identical except for the 2601** type of the return value and that if the number of rows modified by the 2602** connection exceeds the maximum value supported by type "int", then 2603** the return value of sqlite3_total_changes() is undefined. ^Executing 2604** any other type of SQL statement does not affect the value returned by 2605** sqlite3_total_changes(). 2606** 2607** ^Changes made as part of [foreign key actions] are included in the 2608** count, but those made as part of REPLACE constraint resolution are 2609** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2610** are not counted. 2611** 2612** The [sqlite3_total_changes(D)] interface only reports the number 2613** of rows that changed due to SQL statement run against database 2614** connection D. Any changes by other database connections are ignored. 2615** To detect changes against a database file from other database 2616** connections use the [PRAGMA data_version] command or the 2617** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2618** 2619** If a separate thread makes changes on the same database connection 2620** while [sqlite3_total_changes()] is running then the value 2621** returned is unpredictable and not meaningful. 2622** 2623** See also: 2624** <ul> 2625** <li> the [sqlite3_changes()] interface 2626** <li> the [count_changes pragma] 2627** <li> the [changes() SQL function] 2628** <li> the [data_version pragma] 2629** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2630** </ul> 2631*/ 2632int sqlite3_total_changes(sqlite3*); 2633sqlite3_int64 sqlite3_total_changes64(sqlite3*); 2634 2635/* 2636** CAPI3REF: Interrupt A Long-Running Query 2637** METHOD: sqlite3 2638** 2639** ^This function causes any pending database operation to abort and 2640** return at its earliest opportunity. This routine is typically 2641** called in response to a user action such as pressing "Cancel" 2642** or Ctrl-C where the user wants a long query operation to halt 2643** immediately. 2644** 2645** ^It is safe to call this routine from a thread different from the 2646** thread that is currently running the database operation. But it 2647** is not safe to call this routine with a [database connection] that 2648** is closed or might close before sqlite3_interrupt() returns. 2649** 2650** ^If an SQL operation is very nearly finished at the time when 2651** sqlite3_interrupt() is called, then it might not have an opportunity 2652** to be interrupted and might continue to completion. 2653** 2654** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2655** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2656** that is inside an explicit transaction, then the entire transaction 2657** will be rolled back automatically. 2658** 2659** ^The sqlite3_interrupt(D) call is in effect until all currently running 2660** SQL statements on [database connection] D complete. ^Any new SQL statements 2661** that are started after the sqlite3_interrupt() call and before the 2662** running statement count reaches zero are interrupted as if they had been 2663** running prior to the sqlite3_interrupt() call. ^New SQL statements 2664** that are started after the running statement count reaches zero are 2665** not effected by the sqlite3_interrupt(). 2666** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2667** SQL statements is a no-op and has no effect on SQL statements 2668** that are started after the sqlite3_interrupt() call returns. 2669*/ 2670void sqlite3_interrupt(sqlite3*); 2671 2672/* 2673** CAPI3REF: Determine If An SQL Statement Is Complete 2674** 2675** These routines are useful during command-line input to determine if the 2676** currently entered text seems to form a complete SQL statement or 2677** if additional input is needed before sending the text into 2678** SQLite for parsing. ^These routines return 1 if the input string 2679** appears to be a complete SQL statement. ^A statement is judged to be 2680** complete if it ends with a semicolon token and is not a prefix of a 2681** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2682** string literals or quoted identifier names or comments are not 2683** independent tokens (they are part of the token in which they are 2684** embedded) and thus do not count as a statement terminator. ^Whitespace 2685** and comments that follow the final semicolon are ignored. 2686** 2687** ^These routines return 0 if the statement is incomplete. ^If a 2688** memory allocation fails, then SQLITE_NOMEM is returned. 2689** 2690** ^These routines do not parse the SQL statements thus 2691** will not detect syntactically incorrect SQL. 2692** 2693** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2694** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2695** automatically by sqlite3_complete16(). If that initialization fails, 2696** then the return value from sqlite3_complete16() will be non-zero 2697** regardless of whether or not the input SQL is complete.)^ 2698** 2699** The input to [sqlite3_complete()] must be a zero-terminated 2700** UTF-8 string. 2701** 2702** The input to [sqlite3_complete16()] must be a zero-terminated 2703** UTF-16 string in native byte order. 2704*/ 2705int sqlite3_complete(const char *sql); 2706int sqlite3_complete16(const void *sql); 2707 2708/* 2709** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2710** KEYWORDS: {busy-handler callback} {busy handler} 2711** METHOD: sqlite3 2712** 2713** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2714** that might be invoked with argument P whenever 2715** an attempt is made to access a database table associated with 2716** [database connection] D when another thread 2717** or process has the table locked. 2718** The sqlite3_busy_handler() interface is used to implement 2719** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2720** 2721** ^If the busy callback is NULL, then [SQLITE_BUSY] 2722** is returned immediately upon encountering the lock. ^If the busy callback 2723** is not NULL, then the callback might be invoked with two arguments. 2724** 2725** ^The first argument to the busy handler is a copy of the void* pointer which 2726** is the third argument to sqlite3_busy_handler(). ^The second argument to 2727** the busy handler callback is the number of times that the busy handler has 2728** been invoked previously for the same locking event. ^If the 2729** busy callback returns 0, then no additional attempts are made to 2730** access the database and [SQLITE_BUSY] is returned 2731** to the application. 2732** ^If the callback returns non-zero, then another attempt 2733** is made to access the database and the cycle repeats. 2734** 2735** The presence of a busy handler does not guarantee that it will be invoked 2736** when there is lock contention. ^If SQLite determines that invoking the busy 2737** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2738** to the application instead of invoking the 2739** busy handler. 2740** Consider a scenario where one process is holding a read lock that 2741** it is trying to promote to a reserved lock and 2742** a second process is holding a reserved lock that it is trying 2743** to promote to an exclusive lock. The first process cannot proceed 2744** because it is blocked by the second and the second process cannot 2745** proceed because it is blocked by the first. If both processes 2746** invoke the busy handlers, neither will make any progress. Therefore, 2747** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2748** will induce the first process to release its read lock and allow 2749** the second process to proceed. 2750** 2751** ^The default busy callback is NULL. 2752** 2753** ^(There can only be a single busy handler defined for each 2754** [database connection]. Setting a new busy handler clears any 2755** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2756** or evaluating [PRAGMA busy_timeout=N] will change the 2757** busy handler and thus clear any previously set busy handler. 2758** 2759** The busy callback should not take any actions which modify the 2760** database connection that invoked the busy handler. In other words, 2761** the busy handler is not reentrant. Any such actions 2762** result in undefined behavior. 2763** 2764** A busy handler must not close the database connection 2765** or [prepared statement] that invoked the busy handler. 2766*/ 2767int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2768 2769/* 2770** CAPI3REF: Set A Busy Timeout 2771** METHOD: sqlite3 2772** 2773** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2774** for a specified amount of time when a table is locked. ^The handler 2775** will sleep multiple times until at least "ms" milliseconds of sleeping 2776** have accumulated. ^After at least "ms" milliseconds of sleeping, 2777** the handler returns 0 which causes [sqlite3_step()] to return 2778** [SQLITE_BUSY]. 2779** 2780** ^Calling this routine with an argument less than or equal to zero 2781** turns off all busy handlers. 2782** 2783** ^(There can only be a single busy handler for a particular 2784** [database connection] at any given moment. If another busy handler 2785** was defined (using [sqlite3_busy_handler()]) prior to calling 2786** this routine, that other busy handler is cleared.)^ 2787** 2788** See also: [PRAGMA busy_timeout] 2789*/ 2790int sqlite3_busy_timeout(sqlite3*, int ms); 2791 2792/* 2793** CAPI3REF: Convenience Routines For Running Queries 2794** METHOD: sqlite3 2795** 2796** This is a legacy interface that is preserved for backwards compatibility. 2797** Use of this interface is not recommended. 2798** 2799** Definition: A <b>result table</b> is memory data structure created by the 2800** [sqlite3_get_table()] interface. A result table records the 2801** complete query results from one or more queries. 2802** 2803** The table conceptually has a number of rows and columns. But 2804** these numbers are not part of the result table itself. These 2805** numbers are obtained separately. Let N be the number of rows 2806** and M be the number of columns. 2807** 2808** A result table is an array of pointers to zero-terminated UTF-8 strings. 2809** There are (N+1)*M elements in the array. The first M pointers point 2810** to zero-terminated strings that contain the names of the columns. 2811** The remaining entries all point to query results. NULL values result 2812** in NULL pointers. All other values are in their UTF-8 zero-terminated 2813** string representation as returned by [sqlite3_column_text()]. 2814** 2815** A result table might consist of one or more memory allocations. 2816** It is not safe to pass a result table directly to [sqlite3_free()]. 2817** A result table should be deallocated using [sqlite3_free_table()]. 2818** 2819** ^(As an example of the result table format, suppose a query result 2820** is as follows: 2821** 2822** <blockquote><pre> 2823** Name | Age 2824** ----------------------- 2825** Alice | 43 2826** Bob | 28 2827** Cindy | 21 2828** </pre></blockquote> 2829** 2830** There are two columns (M==2) and three rows (N==3). Thus the 2831** result table has 8 entries. Suppose the result table is stored 2832** in an array named azResult. Then azResult holds this content: 2833** 2834** <blockquote><pre> 2835** azResult[0] = "Name"; 2836** azResult[1] = "Age"; 2837** azResult[2] = "Alice"; 2838** azResult[3] = "43"; 2839** azResult[4] = "Bob"; 2840** azResult[5] = "28"; 2841** azResult[6] = "Cindy"; 2842** azResult[7] = "21"; 2843** </pre></blockquote>)^ 2844** 2845** ^The sqlite3_get_table() function evaluates one or more 2846** semicolon-separated SQL statements in the zero-terminated UTF-8 2847** string of its 2nd parameter and returns a result table to the 2848** pointer given in its 3rd parameter. 2849** 2850** After the application has finished with the result from sqlite3_get_table(), 2851** it must pass the result table pointer to sqlite3_free_table() in order to 2852** release the memory that was malloced. Because of the way the 2853** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2854** function must not try to call [sqlite3_free()] directly. Only 2855** [sqlite3_free_table()] is able to release the memory properly and safely. 2856** 2857** The sqlite3_get_table() interface is implemented as a wrapper around 2858** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2859** to any internal data structures of SQLite. It uses only the public 2860** interface defined here. As a consequence, errors that occur in the 2861** wrapper layer outside of the internal [sqlite3_exec()] call are not 2862** reflected in subsequent calls to [sqlite3_errcode()] or 2863** [sqlite3_errmsg()]. 2864*/ 2865int sqlite3_get_table( 2866 sqlite3 *db, /* An open database */ 2867 const char *zSql, /* SQL to be evaluated */ 2868 char ***pazResult, /* Results of the query */ 2869 int *pnRow, /* Number of result rows written here */ 2870 int *pnColumn, /* Number of result columns written here */ 2871 char **pzErrmsg /* Error msg written here */ 2872); 2873void sqlite3_free_table(char **result); 2874 2875/* 2876** CAPI3REF: Formatted String Printing Functions 2877** 2878** These routines are work-alikes of the "printf()" family of functions 2879** from the standard C library. 2880** These routines understand most of the common formatting options from 2881** the standard library printf() 2882** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2883** See the [built-in printf()] documentation for details. 2884** 2885** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2886** results into memory obtained from [sqlite3_malloc64()]. 2887** The strings returned by these two routines should be 2888** released by [sqlite3_free()]. ^Both routines return a 2889** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2890** memory to hold the resulting string. 2891** 2892** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2893** the standard C library. The result is written into the 2894** buffer supplied as the second parameter whose size is given by 2895** the first parameter. Note that the order of the 2896** first two parameters is reversed from snprintf().)^ This is an 2897** historical accident that cannot be fixed without breaking 2898** backwards compatibility. ^(Note also that sqlite3_snprintf() 2899** returns a pointer to its buffer instead of the number of 2900** characters actually written into the buffer.)^ We admit that 2901** the number of characters written would be a more useful return 2902** value but we cannot change the implementation of sqlite3_snprintf() 2903** now without breaking compatibility. 2904** 2905** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2906** guarantees that the buffer is always zero-terminated. ^The first 2907** parameter "n" is the total size of the buffer, including space for 2908** the zero terminator. So the longest string that can be completely 2909** written will be n-1 characters. 2910** 2911** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2912** 2913** See also: [built-in printf()], [printf() SQL function] 2914*/ 2915char *sqlite3_mprintf(const char*,...); 2916char *sqlite3_vmprintf(const char*, va_list); 2917char *sqlite3_snprintf(int,char*,const char*, ...); 2918char *sqlite3_vsnprintf(int,char*,const char*, va_list); 2919 2920/* 2921** CAPI3REF: Memory Allocation Subsystem 2922** 2923** The SQLite core uses these three routines for all of its own 2924** internal memory allocation needs. "Core" in the previous sentence 2925** does not include operating-system specific [VFS] implementation. The 2926** Windows VFS uses native malloc() and free() for some operations. 2927** 2928** ^The sqlite3_malloc() routine returns a pointer to a block 2929** of memory at least N bytes in length, where N is the parameter. 2930** ^If sqlite3_malloc() is unable to obtain sufficient free 2931** memory, it returns a NULL pointer. ^If the parameter N to 2932** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2933** a NULL pointer. 2934** 2935** ^The sqlite3_malloc64(N) routine works just like 2936** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2937** of a signed 32-bit integer. 2938** 2939** ^Calling sqlite3_free() with a pointer previously returned 2940** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2941** that it might be reused. ^The sqlite3_free() routine is 2942** a no-op if is called with a NULL pointer. Passing a NULL pointer 2943** to sqlite3_free() is harmless. After being freed, memory 2944** should neither be read nor written. Even reading previously freed 2945** memory might result in a segmentation fault or other severe error. 2946** Memory corruption, a segmentation fault, or other severe error 2947** might result if sqlite3_free() is called with a non-NULL pointer that 2948** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2949** 2950** ^The sqlite3_realloc(X,N) interface attempts to resize a 2951** prior memory allocation X to be at least N bytes. 2952** ^If the X parameter to sqlite3_realloc(X,N) 2953** is a NULL pointer then its behavior is identical to calling 2954** sqlite3_malloc(N). 2955** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2956** negative then the behavior is exactly the same as calling 2957** sqlite3_free(X). 2958** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2959** of at least N bytes in size or NULL if insufficient memory is available. 2960** ^If M is the size of the prior allocation, then min(N,M) bytes 2961** of the prior allocation are copied into the beginning of buffer returned 2962** by sqlite3_realloc(X,N) and the prior allocation is freed. 2963** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2964** prior allocation is not freed. 2965** 2966** ^The sqlite3_realloc64(X,N) interfaces works the same as 2967** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2968** of a 32-bit signed integer. 2969** 2970** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2971** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2972** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2973** ^The value returned by sqlite3_msize(X) might be larger than the number 2974** of bytes requested when X was allocated. ^If X is a NULL pointer then 2975** sqlite3_msize(X) returns zero. If X points to something that is not 2976** the beginning of memory allocation, or if it points to a formerly 2977** valid memory allocation that has now been freed, then the behavior 2978** of sqlite3_msize(X) is undefined and possibly harmful. 2979** 2980** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2981** sqlite3_malloc64(), and sqlite3_realloc64() 2982** is always aligned to at least an 8 byte boundary, or to a 2983** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2984** option is used. 2985** 2986** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2987** must be either NULL or else pointers obtained from a prior 2988** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2989** not yet been released. 2990** 2991** The application must not read or write any part of 2992** a block of memory after it has been released using 2993** [sqlite3_free()] or [sqlite3_realloc()]. 2994*/ 2995void *sqlite3_malloc(int); 2996void *sqlite3_malloc64(sqlite3_uint64); 2997void *sqlite3_realloc(void*, int); 2998void *sqlite3_realloc64(void*, sqlite3_uint64); 2999void sqlite3_free(void*); 3000sqlite3_uint64 sqlite3_msize(void*); 3001 3002/* 3003** CAPI3REF: Memory Allocator Statistics 3004** 3005** SQLite provides these two interfaces for reporting on the status 3006** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 3007** routines, which form the built-in memory allocation subsystem. 3008** 3009** ^The [sqlite3_memory_used()] routine returns the number of bytes 3010** of memory currently outstanding (malloced but not freed). 3011** ^The [sqlite3_memory_highwater()] routine returns the maximum 3012** value of [sqlite3_memory_used()] since the high-water mark 3013** was last reset. ^The values returned by [sqlite3_memory_used()] and 3014** [sqlite3_memory_highwater()] include any overhead 3015** added by SQLite in its implementation of [sqlite3_malloc()], 3016** but not overhead added by the any underlying system library 3017** routines that [sqlite3_malloc()] may call. 3018** 3019** ^The memory high-water mark is reset to the current value of 3020** [sqlite3_memory_used()] if and only if the parameter to 3021** [sqlite3_memory_highwater()] is true. ^The value returned 3022** by [sqlite3_memory_highwater(1)] is the high-water mark 3023** prior to the reset. 3024*/ 3025sqlite3_int64 sqlite3_memory_used(void); 3026sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 3027 3028/* 3029** CAPI3REF: Pseudo-Random Number Generator 3030** 3031** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 3032** select random [ROWID | ROWIDs] when inserting new records into a table that 3033** already uses the largest possible [ROWID]. The PRNG is also used for 3034** the built-in random() and randomblob() SQL functions. This interface allows 3035** applications to access the same PRNG for other purposes. 3036** 3037** ^A call to this routine stores N bytes of randomness into buffer P. 3038** ^The P parameter can be a NULL pointer. 3039** 3040** ^If this routine has not been previously called or if the previous 3041** call had N less than one or a NULL pointer for P, then the PRNG is 3042** seeded using randomness obtained from the xRandomness method of 3043** the default [sqlite3_vfs] object. 3044** ^If the previous call to this routine had an N of 1 or more and a 3045** non-NULL P then the pseudo-randomness is generated 3046** internally and without recourse to the [sqlite3_vfs] xRandomness 3047** method. 3048*/ 3049void sqlite3_randomness(int N, void *P); 3050 3051/* 3052** CAPI3REF: Compile-Time Authorization Callbacks 3053** METHOD: sqlite3 3054** KEYWORDS: {authorizer callback} 3055** 3056** ^This routine registers an authorizer callback with a particular 3057** [database connection], supplied in the first argument. 3058** ^The authorizer callback is invoked as SQL statements are being compiled 3059** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 3060** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 3061** and [sqlite3_prepare16_v3()]. ^At various 3062** points during the compilation process, as logic is being created 3063** to perform various actions, the authorizer callback is invoked to 3064** see if those actions are allowed. ^The authorizer callback should 3065** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 3066** specific action but allow the SQL statement to continue to be 3067** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 3068** rejected with an error. ^If the authorizer callback returns 3069** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 3070** then the [sqlite3_prepare_v2()] or equivalent call that triggered 3071** the authorizer will fail with an error message. 3072** 3073** When the callback returns [SQLITE_OK], that means the operation 3074** requested is ok. ^When the callback returns [SQLITE_DENY], the 3075** [sqlite3_prepare_v2()] or equivalent call that triggered the 3076** authorizer will fail with an error message explaining that 3077** access is denied. 3078** 3079** ^The first parameter to the authorizer callback is a copy of the third 3080** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 3081** to the callback is an integer [SQLITE_COPY | action code] that specifies 3082** the particular action to be authorized. ^The third through sixth parameters 3083** to the callback are either NULL pointers or zero-terminated strings 3084** that contain additional details about the action to be authorized. 3085** Applications must always be prepared to encounter a NULL pointer in any 3086** of the third through the sixth parameters of the authorization callback. 3087** 3088** ^If the action code is [SQLITE_READ] 3089** and the callback returns [SQLITE_IGNORE] then the 3090** [prepared statement] statement is constructed to substitute 3091** a NULL value in place of the table column that would have 3092** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 3093** return can be used to deny an untrusted user access to individual 3094** columns of a table. 3095** ^When a table is referenced by a [SELECT] but no column values are 3096** extracted from that table (for example in a query like 3097** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3098** is invoked once for that table with a column name that is an empty string. 3099** ^If the action code is [SQLITE_DELETE] and the callback returns 3100** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3101** [truncate optimization] is disabled and all rows are deleted individually. 3102** 3103** An authorizer is used when [sqlite3_prepare | preparing] 3104** SQL statements from an untrusted source, to ensure that the SQL statements 3105** do not try to access data they are not allowed to see, or that they do not 3106** try to execute malicious statements that damage the database. For 3107** example, an application may allow a user to enter arbitrary 3108** SQL queries for evaluation by a database. But the application does 3109** not want the user to be able to make arbitrary changes to the 3110** database. An authorizer could then be put in place while the 3111** user-entered SQL is being [sqlite3_prepare | prepared] that 3112** disallows everything except [SELECT] statements. 3113** 3114** Applications that need to process SQL from untrusted sources 3115** might also consider lowering resource limits using [sqlite3_limit()] 3116** and limiting database size using the [max_page_count] [PRAGMA] 3117** in addition to using an authorizer. 3118** 3119** ^(Only a single authorizer can be in place on a database connection 3120** at a time. Each call to sqlite3_set_authorizer overrides the 3121** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3122** The authorizer is disabled by default. 3123** 3124** The authorizer callback must not do anything that will modify 3125** the database connection that invoked the authorizer callback. 3126** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3127** database connections for the meaning of "modify" in this paragraph. 3128** 3129** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3130** statement might be re-prepared during [sqlite3_step()] due to a 3131** schema change. Hence, the application should ensure that the 3132** correct authorizer callback remains in place during the [sqlite3_step()]. 3133** 3134** ^Note that the authorizer callback is invoked only during 3135** [sqlite3_prepare()] or its variants. Authorization is not 3136** performed during statement evaluation in [sqlite3_step()], unless 3137** as stated in the previous paragraph, sqlite3_step() invokes 3138** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3139*/ 3140int sqlite3_set_authorizer( 3141 sqlite3*, 3142 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3143 void *pUserData 3144); 3145 3146/* 3147** CAPI3REF: Authorizer Return Codes 3148** 3149** The [sqlite3_set_authorizer | authorizer callback function] must 3150** return either [SQLITE_OK] or one of these two constants in order 3151** to signal SQLite whether or not the action is permitted. See the 3152** [sqlite3_set_authorizer | authorizer documentation] for additional 3153** information. 3154** 3155** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3156** returned from the [sqlite3_vtab_on_conflict()] interface. 3157*/ 3158#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3159#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3160 3161/* 3162** CAPI3REF: Authorizer Action Codes 3163** 3164** The [sqlite3_set_authorizer()] interface registers a callback function 3165** that is invoked to authorize certain SQL statement actions. The 3166** second parameter to the callback is an integer code that specifies 3167** what action is being authorized. These are the integer action codes that 3168** the authorizer callback may be passed. 3169** 3170** These action code values signify what kind of operation is to be 3171** authorized. The 3rd and 4th parameters to the authorization 3172** callback function will be parameters or NULL depending on which of these 3173** codes is used as the second parameter. ^(The 5th parameter to the 3174** authorizer callback is the name of the database ("main", "temp", 3175** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3176** is the name of the inner-most trigger or view that is responsible for 3177** the access attempt or NULL if this access attempt is directly from 3178** top-level SQL code. 3179*/ 3180/******************************************* 3rd ************ 4th ***********/ 3181#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3182#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3183#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3184#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3185#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3186#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3187#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3188#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3189#define SQLITE_DELETE 9 /* Table Name NULL */ 3190#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3191#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3192#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3193#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3194#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3195#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3196#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3197#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3198#define SQLITE_INSERT 18 /* Table Name NULL */ 3199#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3200#define SQLITE_READ 20 /* Table Name Column Name */ 3201#define SQLITE_SELECT 21 /* NULL NULL */ 3202#define SQLITE_TRANSACTION 22 /* Operation NULL */ 3203#define SQLITE_UPDATE 23 /* Table Name Column Name */ 3204#define SQLITE_ATTACH 24 /* Filename NULL */ 3205#define SQLITE_DETACH 25 /* Database Name NULL */ 3206#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3207#define SQLITE_REINDEX 27 /* Index Name NULL */ 3208#define SQLITE_ANALYZE 28 /* Table Name NULL */ 3209#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3210#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3211#define SQLITE_FUNCTION 31 /* NULL Function Name */ 3212#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3213#define SQLITE_COPY 0 /* No longer used */ 3214#define SQLITE_RECURSIVE 33 /* NULL NULL */ 3215 3216/* 3217** CAPI3REF: Tracing And Profiling Functions 3218** METHOD: sqlite3 3219** 3220** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3221** instead of the routines described here. 3222** 3223** These routines register callback functions that can be used for 3224** tracing and profiling the execution of SQL statements. 3225** 3226** ^The callback function registered by sqlite3_trace() is invoked at 3227** various times when an SQL statement is being run by [sqlite3_step()]. 3228** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3229** SQL statement text as the statement first begins executing. 3230** ^(Additional sqlite3_trace() callbacks might occur 3231** as each triggered subprogram is entered. The callbacks for triggers 3232** contain a UTF-8 SQL comment that identifies the trigger.)^ 3233** 3234** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3235** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3236** 3237** ^The callback function registered by sqlite3_profile() is invoked 3238** as each SQL statement finishes. ^The profile callback contains 3239** the original statement text and an estimate of wall-clock time 3240** of how long that statement took to run. ^The profile callback 3241** time is in units of nanoseconds, however the current implementation 3242** is only capable of millisecond resolution so the six least significant 3243** digits in the time are meaningless. Future versions of SQLite 3244** might provide greater resolution on the profiler callback. Invoking 3245** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3246** profile callback. 3247*/ 3248SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3249 void(*xTrace)(void*,const char*), void*); 3250SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3251 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3252 3253/* 3254** CAPI3REF: SQL Trace Event Codes 3255** KEYWORDS: SQLITE_TRACE 3256** 3257** These constants identify classes of events that can be monitored 3258** using the [sqlite3_trace_v2()] tracing logic. The M argument 3259** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3260** the following constants. ^The first argument to the trace callback 3261** is one of the following constants. 3262** 3263** New tracing constants may be added in future releases. 3264** 3265** ^A trace callback has four arguments: xCallback(T,C,P,X). 3266** ^The T argument is one of the integer type codes above. 3267** ^The C argument is a copy of the context pointer passed in as the 3268** fourth argument to [sqlite3_trace_v2()]. 3269** The P and X arguments are pointers whose meanings depend on T. 3270** 3271** <dl> 3272** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3273** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3274** first begins running and possibly at other times during the 3275** execution of the prepared statement, such as at the start of each 3276** trigger subprogram. ^The P argument is a pointer to the 3277** [prepared statement]. ^The X argument is a pointer to a string which 3278** is the unexpanded SQL text of the prepared statement or an SQL comment 3279** that indicates the invocation of a trigger. ^The callback can compute 3280** the same text that would have been returned by the legacy [sqlite3_trace()] 3281** interface by using the X argument when X begins with "--" and invoking 3282** [sqlite3_expanded_sql(P)] otherwise. 3283** 3284** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3285** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3286** information as is provided by the [sqlite3_profile()] callback. 3287** ^The P argument is a pointer to the [prepared statement] and the 3288** X argument points to a 64-bit integer which is the estimated of 3289** the number of nanosecond that the prepared statement took to run. 3290** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3291** 3292** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3293** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3294** statement generates a single row of result. 3295** ^The P argument is a pointer to the [prepared statement] and the 3296** X argument is unused. 3297** 3298** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3299** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3300** connection closes. 3301** ^The P argument is a pointer to the [database connection] object 3302** and the X argument is unused. 3303** </dl> 3304*/ 3305#define SQLITE_TRACE_STMT 0x01 3306#define SQLITE_TRACE_PROFILE 0x02 3307#define SQLITE_TRACE_ROW 0x04 3308#define SQLITE_TRACE_CLOSE 0x08 3309 3310/* 3311** CAPI3REF: SQL Trace Hook 3312** METHOD: sqlite3 3313** 3314** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3315** function X against [database connection] D, using property mask M 3316** and context pointer P. ^If the X callback is 3317** NULL or if the M mask is zero, then tracing is disabled. The 3318** M argument should be the bitwise OR-ed combination of 3319** zero or more [SQLITE_TRACE] constants. 3320** 3321** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 3322** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). 3323** 3324** ^The X callback is invoked whenever any of the events identified by 3325** mask M occur. ^The integer return value from the callback is currently 3326** ignored, though this may change in future releases. Callback 3327** implementations should return zero to ensure future compatibility. 3328** 3329** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3330** ^The T argument is one of the [SQLITE_TRACE] 3331** constants to indicate why the callback was invoked. 3332** ^The C argument is a copy of the context pointer. 3333** The P and X arguments are pointers whose meanings depend on T. 3334** 3335** The sqlite3_trace_v2() interface is intended to replace the legacy 3336** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3337** are deprecated. 3338*/ 3339int sqlite3_trace_v2( 3340 sqlite3*, 3341 unsigned uMask, 3342 int(*xCallback)(unsigned,void*,void*,void*), 3343 void *pCtx 3344); 3345 3346/* 3347** CAPI3REF: Query Progress Callbacks 3348** METHOD: sqlite3 3349** 3350** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3351** function X to be invoked periodically during long running calls to 3352** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 3353** database connection D. An example use for this 3354** interface is to keep a GUI updated during a large query. 3355** 3356** ^The parameter P is passed through as the only parameter to the 3357** callback function X. ^The parameter N is the approximate number of 3358** [virtual machine instructions] that are evaluated between successive 3359** invocations of the callback X. ^If N is less than one then the progress 3360** handler is disabled. 3361** 3362** ^Only a single progress handler may be defined at one time per 3363** [database connection]; setting a new progress handler cancels the 3364** old one. ^Setting parameter X to NULL disables the progress handler. 3365** ^The progress handler is also disabled by setting N to a value less 3366** than 1. 3367** 3368** ^If the progress callback returns non-zero, the operation is 3369** interrupted. This feature can be used to implement a 3370** "Cancel" button on a GUI progress dialog box. 3371** 3372** The progress handler callback must not do anything that will modify 3373** the database connection that invoked the progress handler. 3374** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3375** database connections for the meaning of "modify" in this paragraph. 3376** 3377*/ 3378void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3379 3380/* 3381** CAPI3REF: Opening A New Database Connection 3382** CONSTRUCTOR: sqlite3 3383** 3384** ^These routines open an SQLite database file as specified by the 3385** filename argument. ^The filename argument is interpreted as UTF-8 for 3386** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3387** order for sqlite3_open16(). ^(A [database connection] handle is usually 3388** returned in *ppDb, even if an error occurs. The only exception is that 3389** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3390** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3391** object.)^ ^(If the database is opened (and/or created) successfully, then 3392** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3393** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3394** an English language description of the error following a failure of any 3395** of the sqlite3_open() routines. 3396** 3397** ^The default encoding will be UTF-8 for databases created using 3398** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3399** created using sqlite3_open16() will be UTF-16 in the native byte order. 3400** 3401** Whether or not an error occurs when it is opened, resources 3402** associated with the [database connection] handle should be released by 3403** passing it to [sqlite3_close()] when it is no longer required. 3404** 3405** The sqlite3_open_v2() interface works like sqlite3_open() 3406** except that it accepts two additional parameters for additional control 3407** over the new database connection. ^(The flags parameter to 3408** sqlite3_open_v2() must include, at a minimum, one of the following 3409** three flag combinations:)^ 3410** 3411** <dl> 3412** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3413** <dd>The database is opened in read-only mode. If the database does not 3414** already exist, an error is returned.</dd>)^ 3415** 3416** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3417** <dd>The database is opened for reading and writing if possible, or reading 3418** only if the file is write protected by the operating system. In either 3419** case the database must already exist, otherwise an error is returned.</dd>)^ 3420** 3421** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3422** <dd>The database is opened for reading and writing, and is created if 3423** it does not already exist. This is the behavior that is always used for 3424** sqlite3_open() and sqlite3_open16().</dd>)^ 3425** </dl> 3426** 3427** In addition to the required flags, the following optional flags are 3428** also supported: 3429** 3430** <dl> 3431** ^(<dt>[SQLITE_OPEN_URI]</dt> 3432** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3433** 3434** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3435** <dd>The database will be opened as an in-memory database. The database 3436** is named by the "filename" argument for the purposes of cache-sharing, 3437** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3438** </dd>)^ 3439** 3440** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3441** <dd>The new database connection will use the "multi-thread" 3442** [threading mode].)^ This means that separate threads are allowed 3443** to use SQLite at the same time, as long as each thread is using 3444** a different [database connection]. 3445** 3446** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3447** <dd>The new database connection will use the "serialized" 3448** [threading mode].)^ This means the multiple threads can safely 3449** attempt to use the same database connection at the same time. 3450** (Mutexes will block any actual concurrency, but in this mode 3451** there is no harm in trying.) 3452** 3453** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3454** <dd>The database is opened [shared cache] enabled, overriding 3455** the default shared cache setting provided by 3456** [sqlite3_enable_shared_cache()].)^ 3457** The [use of shared cache mode is discouraged] and hence shared cache 3458** capabilities may be omitted from many builds of SQLite. In such cases, 3459** this option is a no-op. 3460** 3461** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3462** <dd>The database is opened [shared cache] disabled, overriding 3463** the default shared cache setting provided by 3464** [sqlite3_enable_shared_cache()].)^ 3465** 3466** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt> 3467** <dd>The database connection comes up in "extended result code mode". 3468** In other words, the database behaves has if 3469** [sqlite3_extended_result_codes(db,1)] where called on the database 3470** connection as soon as the connection is created. In addition to setting 3471** the extended result code mode, this flag also causes [sqlite3_open_v2()] 3472** to return an extended result code.</dd> 3473** 3474** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3475** <dd>The database filename is not allowed to contain a symbolic link</dd> 3476** </dl>)^ 3477** 3478** If the 3rd parameter to sqlite3_open_v2() is not one of the 3479** required combinations shown above optionally combined with other 3480** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3481** then the behavior is undefined. Historic versions of SQLite 3482** have silently ignored surplus bits in the flags parameter to 3483** sqlite3_open_v2(), however that behavior might not be carried through 3484** into future versions of SQLite and so applications should not rely 3485** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op 3486** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause 3487** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE 3488** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not 3489** by sqlite3_open_v2(). 3490** 3491** ^The fourth parameter to sqlite3_open_v2() is the name of the 3492** [sqlite3_vfs] object that defines the operating system interface that 3493** the new database connection should use. ^If the fourth parameter is 3494** a NULL pointer then the default [sqlite3_vfs] object is used. 3495** 3496** ^If the filename is ":memory:", then a private, temporary in-memory database 3497** is created for the connection. ^This in-memory database will vanish when 3498** the database connection is closed. Future versions of SQLite might 3499** make use of additional special filenames that begin with the ":" character. 3500** It is recommended that when a database filename actually does begin with 3501** a ":" character you should prefix the filename with a pathname such as 3502** "./" to avoid ambiguity. 3503** 3504** ^If the filename is an empty string, then a private, temporary 3505** on-disk database will be created. ^This private database will be 3506** automatically deleted as soon as the database connection is closed. 3507** 3508** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3509** 3510** ^If [URI filename] interpretation is enabled, and the filename argument 3511** begins with "file:", then the filename is interpreted as a URI. ^URI 3512** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3513** set in the third argument to sqlite3_open_v2(), or if it has 3514** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3515** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3516** URI filename interpretation is turned off 3517** by default, but future releases of SQLite might enable URI filename 3518** interpretation by default. See "[URI filenames]" for additional 3519** information. 3520** 3521** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3522** authority, then it must be either an empty string or the string 3523** "localhost". ^If the authority is not an empty string or "localhost", an 3524** error is returned to the caller. ^The fragment component of a URI, if 3525** present, is ignored. 3526** 3527** ^SQLite uses the path component of the URI as the name of the disk file 3528** which contains the database. ^If the path begins with a '/' character, 3529** then it is interpreted as an absolute path. ^If the path does not begin 3530** with a '/' (meaning that the authority section is omitted from the URI) 3531** then the path is interpreted as a relative path. 3532** ^(On windows, the first component of an absolute path 3533** is a drive specification (e.g. "C:").)^ 3534** 3535** [[core URI query parameters]] 3536** The query component of a URI may contain parameters that are interpreted 3537** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3538** SQLite and its built-in [VFSes] interpret the 3539** following query parameters: 3540** 3541** <ul> 3542** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3543** a VFS object that provides the operating system interface that should 3544** be used to access the database file on disk. ^If this option is set to 3545** an empty string the default VFS object is used. ^Specifying an unknown 3546** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3547** present, then the VFS specified by the option takes precedence over 3548** the value passed as the fourth parameter to sqlite3_open_v2(). 3549** 3550** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3551** "rwc", or "memory". Attempting to set it to any other value is 3552** an error)^. 3553** ^If "ro" is specified, then the database is opened for read-only 3554** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3555** third argument to sqlite3_open_v2(). ^If the mode option is set to 3556** "rw", then the database is opened for read-write (but not create) 3557** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3558** been set. ^Value "rwc" is equivalent to setting both 3559** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3560** set to "memory" then a pure [in-memory database] that never reads 3561** or writes from disk is used. ^It is an error to specify a value for 3562** the mode parameter that is less restrictive than that specified by 3563** the flags passed in the third parameter to sqlite3_open_v2(). 3564** 3565** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3566** "private". ^Setting it to "shared" is equivalent to setting the 3567** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3568** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3569** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3570** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3571** a URI filename, its value overrides any behavior requested by setting 3572** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3573** 3574** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3575** [powersafe overwrite] property does or does not apply to the 3576** storage media on which the database file resides. 3577** 3578** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3579** which if set disables file locking in rollback journal modes. This 3580** is useful for accessing a database on a filesystem that does not 3581** support locking. Caution: Database corruption might result if two 3582** or more processes write to the same database and any one of those 3583** processes uses nolock=1. 3584** 3585** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3586** parameter that indicates that the database file is stored on 3587** read-only media. ^When immutable is set, SQLite assumes that the 3588** database file cannot be changed, even by a process with higher 3589** privilege, and so the database is opened read-only and all locking 3590** and change detection is disabled. Caution: Setting the immutable 3591** property on a database file that does in fact change can result 3592** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3593** See also: [SQLITE_IOCAP_IMMUTABLE]. 3594** 3595** </ul> 3596** 3597** ^Specifying an unknown parameter in the query component of a URI is not an 3598** error. Future versions of SQLite might understand additional query 3599** parameters. See "[query parameters with special meaning to SQLite]" for 3600** additional information. 3601** 3602** [[URI filename examples]] <h3>URI filename examples</h3> 3603** 3604** <table border="1" align=center cellpadding=5> 3605** <tr><th> URI filenames <th> Results 3606** <tr><td> file:data.db <td> 3607** Open the file "data.db" in the current directory. 3608** <tr><td> file:/home/fred/data.db<br> 3609** file:///home/fred/data.db <br> 3610** file://localhost/home/fred/data.db <br> <td> 3611** Open the database file "/home/fred/data.db". 3612** <tr><td> file://darkstar/home/fred/data.db <td> 3613** An error. "darkstar" is not a recognized authority. 3614** <tr><td style="white-space:nowrap"> 3615** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3616** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3617** C:. Note that the %20 escaping in this example is not strictly 3618** necessary - space characters can be used literally 3619** in URI filenames. 3620** <tr><td> file:data.db?mode=ro&cache=private <td> 3621** Open file "data.db" in the current directory for read-only access. 3622** Regardless of whether or not shared-cache mode is enabled by 3623** default, use a private cache. 3624** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3625** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3626** that uses dot-files in place of posix advisory locking. 3627** <tr><td> file:data.db?mode=readonly <td> 3628** An error. "readonly" is not a valid option for the "mode" parameter. 3629** Use "ro" instead: "file:data.db?mode=ro". 3630** </table> 3631** 3632** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3633** query components of a URI. A hexadecimal escape sequence consists of a 3634** percent sign - "%" - followed by exactly two hexadecimal digits 3635** specifying an octet value. ^Before the path or query components of a 3636** URI filename are interpreted, they are encoded using UTF-8 and all 3637** hexadecimal escape sequences replaced by a single byte containing the 3638** corresponding octet. If this process generates an invalid UTF-8 encoding, 3639** the results are undefined. 3640** 3641** <b>Note to Windows users:</b> The encoding used for the filename argument 3642** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3643** codepage is currently defined. Filenames containing international 3644** characters must be converted to UTF-8 prior to passing them into 3645** sqlite3_open() or sqlite3_open_v2(). 3646** 3647** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3648** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3649** features that require the use of temporary files may fail. 3650** 3651** See also: [sqlite3_temp_directory] 3652*/ 3653int sqlite3_open( 3654 const char *filename, /* Database filename (UTF-8) */ 3655 sqlite3 **ppDb /* OUT: SQLite db handle */ 3656); 3657int sqlite3_open16( 3658 const void *filename, /* Database filename (UTF-16) */ 3659 sqlite3 **ppDb /* OUT: SQLite db handle */ 3660); 3661int sqlite3_open_v2( 3662 const char *filename, /* Database filename (UTF-8) */ 3663 sqlite3 **ppDb, /* OUT: SQLite db handle */ 3664 int flags, /* Flags */ 3665 const char *zVfs /* Name of VFS module to use */ 3666); 3667 3668/* 3669** CAPI3REF: Obtain Values For URI Parameters 3670** 3671** These are utility routines, useful to [VFS|custom VFS implementations], 3672** that check if a database file was a URI that contained a specific query 3673** parameter, and if so obtains the value of that query parameter. 3674** 3675** The first parameter to these interfaces (hereafter referred to 3676** as F) must be one of: 3677** <ul> 3678** <li> A database filename pointer created by the SQLite core and 3679** passed into the xOpen() method of a VFS implemention, or 3680** <li> A filename obtained from [sqlite3_db_filename()], or 3681** <li> A new filename constructed using [sqlite3_create_filename()]. 3682** </ul> 3683** If the F parameter is not one of the above, then the behavior is 3684** undefined and probably undesirable. Older versions of SQLite were 3685** more tolerant of invalid F parameters than newer versions. 3686** 3687** If F is a suitable filename (as described in the previous paragraph) 3688** and if P is the name of the query parameter, then 3689** sqlite3_uri_parameter(F,P) returns the value of the P 3690** parameter if it exists or a NULL pointer if P does not appear as a 3691** query parameter on F. If P is a query parameter of F and it 3692** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3693** a pointer to an empty string. 3694** 3695** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3696** parameter and returns true (1) or false (0) according to the value 3697** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3698** value of query parameter P is one of "yes", "true", or "on" in any 3699** case or if the value begins with a non-zero number. The 3700** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3701** query parameter P is one of "no", "false", or "off" in any case or 3702** if the value begins with a numeric zero. If P is not a query 3703** parameter on F or if the value of P does not match any of the 3704** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3705** 3706** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3707** 64-bit signed integer and returns that integer, or D if P does not 3708** exist. If the value of P is something other than an integer, then 3709** zero is returned. 3710** 3711** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3712** the value) of the N-th query parameter for filename F, or a NULL 3713** pointer if N is less than zero or greater than the number of query 3714** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3715** the name of the first query parameter, 1 for the second parameter, and 3716** so forth. 3717** 3718** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3719** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3720** is not a database file pathname pointer that the SQLite core passed 3721** into the xOpen VFS method, then the behavior of this routine is undefined 3722** and probably undesirable. 3723** 3724** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3725** parameter can also be the name of a rollback journal file or WAL file 3726** in addition to the main database file. Prior to version 3.31.0, these 3727** routines would only work if F was the name of the main database file. 3728** When the F parameter is the name of the rollback journal or WAL file, 3729** it has access to all the same query parameters as were found on the 3730** main database file. 3731** 3732** See the [URI filename] documentation for additional information. 3733*/ 3734const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam); 3735int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault); 3736sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64); 3737const char *sqlite3_uri_key(sqlite3_filename z, int N); 3738 3739/* 3740** CAPI3REF: Translate filenames 3741** 3742** These routines are available to [VFS|custom VFS implementations] for 3743** translating filenames between the main database file, the journal file, 3744** and the WAL file. 3745** 3746** If F is the name of an sqlite database file, journal file, or WAL file 3747** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3748** returns the name of the corresponding database file. 3749** 3750** If F is the name of an sqlite database file, journal file, or WAL file 3751** passed by the SQLite core into the VFS, or if F is a database filename 3752** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3753** returns the name of the corresponding rollback journal file. 3754** 3755** If F is the name of an sqlite database file, journal file, or WAL file 3756** that was passed by the SQLite core into the VFS, or if F is a database 3757** filename obtained from [sqlite3_db_filename()], then 3758** sqlite3_filename_wal(F) returns the name of the corresponding 3759** WAL file. 3760** 3761** In all of the above, if F is not the name of a database, journal or WAL 3762** filename passed into the VFS from the SQLite core and F is not the 3763** return value from [sqlite3_db_filename()], then the result is 3764** undefined and is likely a memory access violation. 3765*/ 3766const char *sqlite3_filename_database(sqlite3_filename); 3767const char *sqlite3_filename_journal(sqlite3_filename); 3768const char *sqlite3_filename_wal(sqlite3_filename); 3769 3770/* 3771** CAPI3REF: Database File Corresponding To A Journal 3772** 3773** ^If X is the name of a rollback or WAL-mode journal file that is 3774** passed into the xOpen method of [sqlite3_vfs], then 3775** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 3776** object that represents the main database file. 3777** 3778** This routine is intended for use in custom [VFS] implementations 3779** only. It is not a general-purpose interface. 3780** The argument sqlite3_file_object(X) must be a filename pointer that 3781** has been passed into [sqlite3_vfs].xOpen method where the 3782** flags parameter to xOpen contains one of the bits 3783** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 3784** of this routine results in undefined and probably undesirable 3785** behavior. 3786*/ 3787sqlite3_file *sqlite3_database_file_object(const char*); 3788 3789/* 3790** CAPI3REF: Create and Destroy VFS Filenames 3791** 3792** These interfces are provided for use by [VFS shim] implementations and 3793** are not useful outside of that context. 3794** 3795** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 3796** database filename D with corresponding journal file J and WAL file W and 3797** with N URI parameters key/values pairs in the array P. The result from 3798** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 3799** is safe to pass to routines like: 3800** <ul> 3801** <li> [sqlite3_uri_parameter()], 3802** <li> [sqlite3_uri_boolean()], 3803** <li> [sqlite3_uri_int64()], 3804** <li> [sqlite3_uri_key()], 3805** <li> [sqlite3_filename_database()], 3806** <li> [sqlite3_filename_journal()], or 3807** <li> [sqlite3_filename_wal()]. 3808** </ul> 3809** If a memory allocation error occurs, sqlite3_create_filename() might 3810** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 3811** must be released by a corresponding call to sqlite3_free_filename(Y). 3812** 3813** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 3814** of 2*N pointers to strings. Each pair of pointers in this array corresponds 3815** to a key and value for a query parameter. The P parameter may be a NULL 3816** pointer if N is zero. None of the 2*N pointers in the P array may be 3817** NULL pointers and key pointers should not be empty strings. 3818** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 3819** be NULL pointers, though they can be empty strings. 3820** 3821** The sqlite3_free_filename(Y) routine releases a memory allocation 3822** previously obtained from sqlite3_create_filename(). Invoking 3823** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 3824** 3825** If the Y parameter to sqlite3_free_filename(Y) is anything other 3826** than a NULL pointer or a pointer previously acquired from 3827** sqlite3_create_filename(), then bad things such as heap 3828** corruption or segfaults may occur. The value Y should not be 3829** used again after sqlite3_free_filename(Y) has been called. This means 3830** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 3831** then the corresponding [sqlite3_module.xClose() method should also be 3832** invoked prior to calling sqlite3_free_filename(Y). 3833*/ 3834sqlite3_filename sqlite3_create_filename( 3835 const char *zDatabase, 3836 const char *zJournal, 3837 const char *zWal, 3838 int nParam, 3839 const char **azParam 3840); 3841void sqlite3_free_filename(sqlite3_filename); 3842 3843/* 3844** CAPI3REF: Error Codes And Messages 3845** METHOD: sqlite3 3846** 3847** ^If the most recent sqlite3_* API call associated with 3848** [database connection] D failed, then the sqlite3_errcode(D) interface 3849** returns the numeric [result code] or [extended result code] for that 3850** API call. 3851** ^The sqlite3_extended_errcode() 3852** interface is the same except that it always returns the 3853** [extended result code] even when extended result codes are 3854** disabled. 3855** 3856** The values returned by sqlite3_errcode() and/or 3857** sqlite3_extended_errcode() might change with each API call. 3858** Except, there are some interfaces that are guaranteed to never 3859** change the value of the error code. The error-code preserving 3860** interfaces include the following: 3861** 3862** <ul> 3863** <li> sqlite3_errcode() 3864** <li> sqlite3_extended_errcode() 3865** <li> sqlite3_errmsg() 3866** <li> sqlite3_errmsg16() 3867** <li> sqlite3_error_offset() 3868** </ul> 3869** 3870** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3871** text that describes the error, as either UTF-8 or UTF-16 respectively. 3872** ^(Memory to hold the error message string is managed internally. 3873** The application does not need to worry about freeing the result. 3874** However, the error string might be overwritten or deallocated by 3875** subsequent calls to other SQLite interface functions.)^ 3876** 3877** ^The sqlite3_errstr() interface returns the English-language text 3878** that describes the [result code], as UTF-8. 3879** ^(Memory to hold the error message string is managed internally 3880** and must not be freed by the application)^. 3881** 3882** ^If the most recent error references a specific token in the input 3883** SQL, the sqlite3_error_offset() interface returns the byte offset 3884** of the start of that token. ^The byte offset returned by 3885** sqlite3_error_offset() assumes that the input SQL is UTF8. 3886** ^If the most recent error does not reference a specific token in the input 3887** SQL, then the sqlite3_error_offset() function returns -1. 3888** 3889** When the serialized [threading mode] is in use, it might be the 3890** case that a second error occurs on a separate thread in between 3891** the time of the first error and the call to these interfaces. 3892** When that happens, the second error will be reported since these 3893** interfaces always report the most recent result. To avoid 3894** this, each thread can obtain exclusive use of the [database connection] D 3895** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3896** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3897** all calls to the interfaces listed here are completed. 3898** 3899** If an interface fails with SQLITE_MISUSE, that means the interface 3900** was invoked incorrectly by the application. In that case, the 3901** error code and message may or may not be set. 3902*/ 3903int sqlite3_errcode(sqlite3 *db); 3904int sqlite3_extended_errcode(sqlite3 *db); 3905const char *sqlite3_errmsg(sqlite3*); 3906const void *sqlite3_errmsg16(sqlite3*); 3907const char *sqlite3_errstr(int); 3908int sqlite3_error_offset(sqlite3 *db); 3909 3910/* 3911** CAPI3REF: Prepared Statement Object 3912** KEYWORDS: {prepared statement} {prepared statements} 3913** 3914** An instance of this object represents a single SQL statement that 3915** has been compiled into binary form and is ready to be evaluated. 3916** 3917** Think of each SQL statement as a separate computer program. The 3918** original SQL text is source code. A prepared statement object 3919** is the compiled object code. All SQL must be converted into a 3920** prepared statement before it can be run. 3921** 3922** The life-cycle of a prepared statement object usually goes like this: 3923** 3924** <ol> 3925** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3926** <li> Bind values to [parameters] using the sqlite3_bind_*() 3927** interfaces. 3928** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3929** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3930** to step 2. Do this zero or more times. 3931** <li> Destroy the object using [sqlite3_finalize()]. 3932** </ol> 3933*/ 3934typedef struct sqlite3_stmt sqlite3_stmt; 3935 3936/* 3937** CAPI3REF: Run-time Limits 3938** METHOD: sqlite3 3939** 3940** ^(This interface allows the size of various constructs to be limited 3941** on a connection by connection basis. The first parameter is the 3942** [database connection] whose limit is to be set or queried. The 3943** second parameter is one of the [limit categories] that define a 3944** class of constructs to be size limited. The third parameter is the 3945** new limit for that construct.)^ 3946** 3947** ^If the new limit is a negative number, the limit is unchanged. 3948** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3949** [limits | hard upper bound] 3950** set at compile-time by a C preprocessor macro called 3951** [limits | SQLITE_MAX_<i>NAME</i>]. 3952** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3953** ^Attempts to increase a limit above its hard upper bound are 3954** silently truncated to the hard upper bound. 3955** 3956** ^Regardless of whether or not the limit was changed, the 3957** [sqlite3_limit()] interface returns the prior value of the limit. 3958** ^Hence, to find the current value of a limit without changing it, 3959** simply invoke this interface with the third parameter set to -1. 3960** 3961** Run-time limits are intended for use in applications that manage 3962** both their own internal database and also databases that are controlled 3963** by untrusted external sources. An example application might be a 3964** web browser that has its own databases for storing history and 3965** separate databases controlled by JavaScript applications downloaded 3966** off the Internet. The internal databases can be given the 3967** large, default limits. Databases managed by external sources can 3968** be given much smaller limits designed to prevent a denial of service 3969** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3970** interface to further control untrusted SQL. The size of the database 3971** created by an untrusted script can be contained using the 3972** [max_page_count] [PRAGMA]. 3973** 3974** New run-time limit categories may be added in future releases. 3975*/ 3976int sqlite3_limit(sqlite3*, int id, int newVal); 3977 3978/* 3979** CAPI3REF: Run-Time Limit Categories 3980** KEYWORDS: {limit category} {*limit categories} 3981** 3982** These constants define various performance limits 3983** that can be lowered at run-time using [sqlite3_limit()]. 3984** The synopsis of the meanings of the various limits is shown below. 3985** Additional information is available at [limits | Limits in SQLite]. 3986** 3987** <dl> 3988** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3989** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3990** 3991** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3992** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3993** 3994** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3995** <dd>The maximum number of columns in a table definition or in the 3996** result set of a [SELECT] or the maximum number of columns in an index 3997** or in an ORDER BY or GROUP BY clause.</dd>)^ 3998** 3999** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 4000** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 4001** 4002** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 4003** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 4004** 4005** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 4006** <dd>The maximum number of instructions in a virtual machine program 4007** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 4008** the equivalent tries to allocate space for more than this many opcodes 4009** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 4010** 4011** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 4012** <dd>The maximum number of arguments on a function.</dd>)^ 4013** 4014** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 4015** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 4016** 4017** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 4018** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 4019** <dd>The maximum length of the pattern argument to the [LIKE] or 4020** [GLOB] operators.</dd>)^ 4021** 4022** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 4023** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 4024** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 4025** 4026** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 4027** <dd>The maximum depth of recursion for triggers.</dd>)^ 4028** 4029** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 4030** <dd>The maximum number of auxiliary worker threads that a single 4031** [prepared statement] may start.</dd>)^ 4032** </dl> 4033*/ 4034#define SQLITE_LIMIT_LENGTH 0 4035#define SQLITE_LIMIT_SQL_LENGTH 1 4036#define SQLITE_LIMIT_COLUMN 2 4037#define SQLITE_LIMIT_EXPR_DEPTH 3 4038#define SQLITE_LIMIT_COMPOUND_SELECT 4 4039#define SQLITE_LIMIT_VDBE_OP 5 4040#define SQLITE_LIMIT_FUNCTION_ARG 6 4041#define SQLITE_LIMIT_ATTACHED 7 4042#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 4043#define SQLITE_LIMIT_VARIABLE_NUMBER 9 4044#define SQLITE_LIMIT_TRIGGER_DEPTH 10 4045#define SQLITE_LIMIT_WORKER_THREADS 11 4046 4047/* 4048** CAPI3REF: Prepare Flags 4049** 4050** These constants define various flags that can be passed into 4051** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 4052** [sqlite3_prepare16_v3()] interfaces. 4053** 4054** New flags may be added in future releases of SQLite. 4055** 4056** <dl> 4057** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 4058** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 4059** that the prepared statement will be retained for a long time and 4060** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 4061** and [sqlite3_prepare16_v3()] assume that the prepared statement will 4062** be used just once or at most a few times and then destroyed using 4063** [sqlite3_finalize()] relatively soon. The current implementation acts 4064** on this hint by avoiding the use of [lookaside memory] so as not to 4065** deplete the limited store of lookaside memory. Future versions of 4066** SQLite may act on this hint differently. 4067** 4068** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 4069** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 4070** to be required for any prepared statement that wanted to use the 4071** [sqlite3_normalized_sql()] interface. However, the 4072** [sqlite3_normalized_sql()] interface is now available to all 4073** prepared statements, regardless of whether or not they use this 4074** flag. 4075** 4076** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 4077** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 4078** to return an error (error code SQLITE_ERROR) if the statement uses 4079** any virtual tables. 4080** </dl> 4081*/ 4082#define SQLITE_PREPARE_PERSISTENT 0x01 4083#define SQLITE_PREPARE_NORMALIZE 0x02 4084#define SQLITE_PREPARE_NO_VTAB 0x04 4085 4086/* 4087** CAPI3REF: Compiling An SQL Statement 4088** KEYWORDS: {SQL statement compiler} 4089** METHOD: sqlite3 4090** CONSTRUCTOR: sqlite3_stmt 4091** 4092** To execute an SQL statement, it must first be compiled into a byte-code 4093** program using one of these routines. Or, in other words, these routines 4094** are constructors for the [prepared statement] object. 4095** 4096** The preferred routine to use is [sqlite3_prepare_v2()]. The 4097** [sqlite3_prepare()] interface is legacy and should be avoided. 4098** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 4099** for special purposes. 4100** 4101** The use of the UTF-8 interfaces is preferred, as SQLite currently 4102** does all parsing using UTF-8. The UTF-16 interfaces are provided 4103** as a convenience. The UTF-16 interfaces work by converting the 4104** input text into UTF-8, then invoking the corresponding UTF-8 interface. 4105** 4106** The first argument, "db", is a [database connection] obtained from a 4107** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 4108** [sqlite3_open16()]. The database connection must not have been closed. 4109** 4110** The second argument, "zSql", is the statement to be compiled, encoded 4111** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 4112** and sqlite3_prepare_v3() 4113** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 4114** and sqlite3_prepare16_v3() use UTF-16. 4115** 4116** ^If the nByte argument is negative, then zSql is read up to the 4117** first zero terminator. ^If nByte is positive, then it is the 4118** number of bytes read from zSql. ^If nByte is zero, then no prepared 4119** statement is generated. 4120** If the caller knows that the supplied string is nul-terminated, then 4121** there is a small performance advantage to passing an nByte parameter that 4122** is the number of bytes in the input string <i>including</i> 4123** the nul-terminator. 4124** 4125** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4126** past the end of the first SQL statement in zSql. These routines only 4127** compile the first statement in zSql, so *pzTail is left pointing to 4128** what remains uncompiled. 4129** 4130** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4131** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4132** to NULL. ^If the input text contains no SQL (if the input is an empty 4133** string or a comment) then *ppStmt is set to NULL. 4134** The calling procedure is responsible for deleting the compiled 4135** SQL statement using [sqlite3_finalize()] after it has finished with it. 4136** ppStmt may not be NULL. 4137** 4138** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4139** otherwise an [error code] is returned. 4140** 4141** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4142** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4143** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4144** are retained for backwards compatibility, but their use is discouraged. 4145** ^In the "vX" interfaces, the prepared statement 4146** that is returned (the [sqlite3_stmt] object) contains a copy of the 4147** original SQL text. This causes the [sqlite3_step()] interface to 4148** behave differently in three ways: 4149** 4150** <ol> 4151** <li> 4152** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4153** always used to do, [sqlite3_step()] will automatically recompile the SQL 4154** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4155** retries will occur before sqlite3_step() gives up and returns an error. 4156** </li> 4157** 4158** <li> 4159** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4160** [error codes] or [extended error codes]. ^The legacy behavior was that 4161** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4162** and the application would have to make a second call to [sqlite3_reset()] 4163** in order to find the underlying cause of the problem. With the "v2" prepare 4164** interfaces, the underlying reason for the error is returned immediately. 4165** </li> 4166** 4167** <li> 4168** ^If the specific value bound to a [parameter | host parameter] in the 4169** WHERE clause might influence the choice of query plan for a statement, 4170** then the statement will be automatically recompiled, as if there had been 4171** a schema change, on the first [sqlite3_step()] call following any change 4172** to the [sqlite3_bind_text | bindings] of that [parameter]. 4173** ^The specific value of a WHERE-clause [parameter] might influence the 4174** choice of query plan if the parameter is the left-hand side of a [LIKE] 4175** or [GLOB] operator or if the parameter is compared to an indexed column 4176** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4177** </li> 4178** </ol> 4179** 4180** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4181** the extra prepFlags parameter, which is a bit array consisting of zero or 4182** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4183** sqlite3_prepare_v2() interface works exactly the same as 4184** sqlite3_prepare_v3() with a zero prepFlags parameter. 4185*/ 4186int sqlite3_prepare( 4187 sqlite3 *db, /* Database handle */ 4188 const char *zSql, /* SQL statement, UTF-8 encoded */ 4189 int nByte, /* Maximum length of zSql in bytes. */ 4190 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4191 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4192); 4193int sqlite3_prepare_v2( 4194 sqlite3 *db, /* Database handle */ 4195 const char *zSql, /* SQL statement, UTF-8 encoded */ 4196 int nByte, /* Maximum length of zSql in bytes. */ 4197 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4198 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4199); 4200int sqlite3_prepare_v3( 4201 sqlite3 *db, /* Database handle */ 4202 const char *zSql, /* SQL statement, UTF-8 encoded */ 4203 int nByte, /* Maximum length of zSql in bytes. */ 4204 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4205 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4206 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4207); 4208int sqlite3_prepare16( 4209 sqlite3 *db, /* Database handle */ 4210 const void *zSql, /* SQL statement, UTF-16 encoded */ 4211 int nByte, /* Maximum length of zSql in bytes. */ 4212 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4213 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4214); 4215int sqlite3_prepare16_v2( 4216 sqlite3 *db, /* Database handle */ 4217 const void *zSql, /* SQL statement, UTF-16 encoded */ 4218 int nByte, /* Maximum length of zSql in bytes. */ 4219 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4220 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4221); 4222int sqlite3_prepare16_v3( 4223 sqlite3 *db, /* Database handle */ 4224 const void *zSql, /* SQL statement, UTF-16 encoded */ 4225 int nByte, /* Maximum length of zSql in bytes. */ 4226 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4227 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4228 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4229); 4230 4231/* 4232** CAPI3REF: Retrieving Statement SQL 4233** METHOD: sqlite3_stmt 4234** 4235** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4236** SQL text used to create [prepared statement] P if P was 4237** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4238** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4239** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4240** string containing the SQL text of prepared statement P with 4241** [bound parameters] expanded. 4242** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4243** string containing the normalized SQL text of prepared statement P. The 4244** semantics used to normalize a SQL statement are unspecified and subject 4245** to change. At a minimum, literal values will be replaced with suitable 4246** placeholders. 4247** 4248** ^(For example, if a prepared statement is created using the SQL 4249** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4250** and parameter :xyz is unbound, then sqlite3_sql() will return 4251** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4252** will return "SELECT 2345,NULL".)^ 4253** 4254** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4255** is available to hold the result, or if the result would exceed the 4256** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4257** 4258** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4259** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4260** option causes sqlite3_expanded_sql() to always return NULL. 4261** 4262** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4263** are managed by SQLite and are automatically freed when the prepared 4264** statement is finalized. 4265** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4266** is obtained from [sqlite3_malloc()] and must be freed by the application 4267** by passing it to [sqlite3_free()]. 4268** 4269** ^The sqlite3_normalized_sql() interface is only available if 4270** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. 4271*/ 4272const char *sqlite3_sql(sqlite3_stmt *pStmt); 4273char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4274#ifdef SQLITE_ENABLE_NORMALIZE 4275const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4276#endif 4277 4278/* 4279** CAPI3REF: Determine If An SQL Statement Writes The Database 4280** METHOD: sqlite3_stmt 4281** 4282** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4283** and only if the [prepared statement] X makes no direct changes to 4284** the content of the database file. 4285** 4286** Note that [application-defined SQL functions] or 4287** [virtual tables] might change the database indirectly as a side effect. 4288** ^(For example, if an application defines a function "eval()" that 4289** calls [sqlite3_exec()], then the following SQL statement would 4290** change the database file through side-effects: 4291** 4292** <blockquote><pre> 4293** SELECT eval('DELETE FROM t1') FROM t2; 4294** </pre></blockquote> 4295** 4296** But because the [SELECT] statement does not change the database file 4297** directly, sqlite3_stmt_readonly() would still return true.)^ 4298** 4299** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4300** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4301** since the statements themselves do not actually modify the database but 4302** rather they control the timing of when other statements modify the 4303** database. ^The [ATTACH] and [DETACH] statements also cause 4304** sqlite3_stmt_readonly() to return true since, while those statements 4305** change the configuration of a database connection, they do not make 4306** changes to the content of the database files on disk. 4307** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4308** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4309** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4310** sqlite3_stmt_readonly() returns false for those commands. 4311** 4312** ^This routine returns false if there is any possibility that the 4313** statement might change the database file. ^A false return does 4314** not guarantee that the statement will change the database file. 4315** ^For example, an UPDATE statement might have a WHERE clause that 4316** makes it a no-op, but the sqlite3_stmt_readonly() result would still 4317** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a 4318** read-only no-op if the table already exists, but 4319** sqlite3_stmt_readonly() still returns false for such a statement. 4320** 4321** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] 4322** statement, then sqlite3_stmt_readonly(X) returns the same value as 4323** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. 4324*/ 4325int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4326 4327/* 4328** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4329** METHOD: sqlite3_stmt 4330** 4331** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4332** prepared statement S is an EXPLAIN statement, or 2 if the 4333** statement S is an EXPLAIN QUERY PLAN. 4334** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4335** an ordinary statement or a NULL pointer. 4336*/ 4337int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4338 4339/* 4340** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4341** METHOD: sqlite3_stmt 4342** 4343** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4344** [prepared statement] S has been stepped at least once using 4345** [sqlite3_step(S)] but has neither run to completion (returned 4346** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4347** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4348** interface returns false if S is a NULL pointer. If S is not a 4349** NULL pointer and is not a pointer to a valid [prepared statement] 4350** object, then the behavior is undefined and probably undesirable. 4351** 4352** This interface can be used in combination [sqlite3_next_stmt()] 4353** to locate all prepared statements associated with a database 4354** connection that are in need of being reset. This can be used, 4355** for example, in diagnostic routines to search for prepared 4356** statements that are holding a transaction open. 4357*/ 4358int sqlite3_stmt_busy(sqlite3_stmt*); 4359 4360/* 4361** CAPI3REF: Dynamically Typed Value Object 4362** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4363** 4364** SQLite uses the sqlite3_value object to represent all values 4365** that can be stored in a database table. SQLite uses dynamic typing 4366** for the values it stores. ^Values stored in sqlite3_value objects 4367** can be integers, floating point values, strings, BLOBs, or NULL. 4368** 4369** An sqlite3_value object may be either "protected" or "unprotected". 4370** Some interfaces require a protected sqlite3_value. Other interfaces 4371** will accept either a protected or an unprotected sqlite3_value. 4372** Every interface that accepts sqlite3_value arguments specifies 4373** whether or not it requires a protected sqlite3_value. The 4374** [sqlite3_value_dup()] interface can be used to construct a new 4375** protected sqlite3_value from an unprotected sqlite3_value. 4376** 4377** The terms "protected" and "unprotected" refer to whether or not 4378** a mutex is held. An internal mutex is held for a protected 4379** sqlite3_value object but no mutex is held for an unprotected 4380** sqlite3_value object. If SQLite is compiled to be single-threaded 4381** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4382** or if SQLite is run in one of reduced mutex modes 4383** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4384** then there is no distinction between protected and unprotected 4385** sqlite3_value objects and they can be used interchangeably. However, 4386** for maximum code portability it is recommended that applications 4387** still make the distinction between protected and unprotected 4388** sqlite3_value objects even when not strictly required. 4389** 4390** ^The sqlite3_value objects that are passed as parameters into the 4391** implementation of [application-defined SQL functions] are protected. 4392** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] 4393** are protected. 4394** ^The sqlite3_value object returned by 4395** [sqlite3_column_value()] is unprotected. 4396** Unprotected sqlite3_value objects may only be used as arguments 4397** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4398** [sqlite3_value_dup()]. 4399** The [sqlite3_value_blob | sqlite3_value_type()] family of 4400** interfaces require protected sqlite3_value objects. 4401*/ 4402typedef struct sqlite3_value sqlite3_value; 4403 4404/* 4405** CAPI3REF: SQL Function Context Object 4406** 4407** The context in which an SQL function executes is stored in an 4408** sqlite3_context object. ^A pointer to an sqlite3_context object 4409** is always first parameter to [application-defined SQL functions]. 4410** The application-defined SQL function implementation will pass this 4411** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4412** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4413** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4414** and/or [sqlite3_set_auxdata()]. 4415*/ 4416typedef struct sqlite3_context sqlite3_context; 4417 4418/* 4419** CAPI3REF: Binding Values To Prepared Statements 4420** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4421** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4422** METHOD: sqlite3_stmt 4423** 4424** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4425** literals may be replaced by a [parameter] that matches one of following 4426** templates: 4427** 4428** <ul> 4429** <li> ? 4430** <li> ?NNN 4431** <li> :VVV 4432** <li> @VVV 4433** <li> $VVV 4434** </ul> 4435** 4436** In the templates above, NNN represents an integer literal, 4437** and VVV represents an alphanumeric identifier.)^ ^The values of these 4438** parameters (also called "host parameter names" or "SQL parameters") 4439** can be set using the sqlite3_bind_*() routines defined here. 4440** 4441** ^The first argument to the sqlite3_bind_*() routines is always 4442** a pointer to the [sqlite3_stmt] object returned from 4443** [sqlite3_prepare_v2()] or its variants. 4444** 4445** ^The second argument is the index of the SQL parameter to be set. 4446** ^The leftmost SQL parameter has an index of 1. ^When the same named 4447** SQL parameter is used more than once, second and subsequent 4448** occurrences have the same index as the first occurrence. 4449** ^The index for named parameters can be looked up using the 4450** [sqlite3_bind_parameter_index()] API if desired. ^The index 4451** for "?NNN" parameters is the value of NNN. 4452** ^The NNN value must be between 1 and the [sqlite3_limit()] 4453** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4454** 4455** ^The third argument is the value to bind to the parameter. 4456** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4457** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4458** is ignored and the end result is the same as sqlite3_bind_null(). 4459** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4460** it should be a pointer to well-formed UTF8 text. 4461** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4462** it should be a pointer to well-formed UTF16 text. 4463** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4464** it should be a pointer to a well-formed unicode string that is 4465** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 4466** otherwise. 4467** 4468** [[byte-order determination rules]] ^The byte-order of 4469** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4470** found in first character, which is removed, or in the absence of a BOM 4471** the byte order is the native byte order of the host 4472** machine for sqlite3_bind_text16() or the byte order specified in 4473** the 6th parameter for sqlite3_bind_text64().)^ 4474** ^If UTF16 input text contains invalid unicode 4475** characters, then SQLite might change those invalid characters 4476** into the unicode replacement character: U+FFFD. 4477** 4478** ^(In those routines that have a fourth argument, its value is the 4479** number of bytes in the parameter. To be clear: the value is the 4480** number of <u>bytes</u> in the value, not the number of characters.)^ 4481** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4482** is negative, then the length of the string is 4483** the number of bytes up to the first zero terminator. 4484** If the fourth parameter to sqlite3_bind_blob() is negative, then 4485** the behavior is undefined. 4486** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4487** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4488** that parameter must be the byte offset 4489** where the NUL terminator would occur assuming the string were NUL 4490** terminated. If any NUL characters occurs at byte offsets less than 4491** the value of the fourth parameter then the resulting string value will 4492** contain embedded NULs. The result of expressions involving strings 4493** with embedded NULs is undefined. 4494** 4495** ^The fifth argument to the BLOB and string binding interfaces controls 4496** or indicates the lifetime of the object referenced by the third parameter. 4497** These three options exist: 4498** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished 4499** with it may be passed. ^It is called to dispose of the BLOB or string even 4500** if the call to the bind API fails, except the destructor is not called if 4501** the third parameter is a NULL pointer or the fourth parameter is negative. 4502** ^ (2) The special constant, [SQLITE_STATIC], may be passsed to indicate that 4503** the application remains responsible for disposing of the object. ^In this 4504** case, the object and the provided pointer to it must remain valid until 4505** either the prepared statement is finalized or the same SQL parameter is 4506** bound to something else, whichever occurs sooner. 4507** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the 4508** object is to be copied prior to the return from sqlite3_bind_*(). ^The 4509** object and pointer to it must remain valid until then. ^SQLite will then 4510** manage the lifetime of its private copy. 4511** 4512** ^The sixth argument to sqlite3_bind_text64() must be one of 4513** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4514** to specify the encoding of the text in the third parameter. If 4515** the sixth argument to sqlite3_bind_text64() is not one of the 4516** allowed values shown above, or if the text encoding is different 4517** from the encoding specified by the sixth parameter, then the behavior 4518** is undefined. 4519** 4520** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4521** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4522** (just an integer to hold its size) while it is being processed. 4523** Zeroblobs are intended to serve as placeholders for BLOBs whose 4524** content is later written using 4525** [sqlite3_blob_open | incremental BLOB I/O] routines. 4526** ^A negative value for the zeroblob results in a zero-length BLOB. 4527** 4528** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4529** [prepared statement] S to have an SQL value of NULL, but to also be 4530** associated with the pointer P of type T. ^D is either a NULL pointer or 4531** a pointer to a destructor function for P. ^SQLite will invoke the 4532** destructor D with a single argument of P when it is finished using 4533** P. The T parameter should be a static string, preferably a string 4534** literal. The sqlite3_bind_pointer() routine is part of the 4535** [pointer passing interface] added for SQLite 3.20.0. 4536** 4537** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4538** for the [prepared statement] or with a prepared statement for which 4539** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4540** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4541** routine is passed a [prepared statement] that has been finalized, the 4542** result is undefined and probably harmful. 4543** 4544** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4545** ^Unbound parameters are interpreted as NULL. 4546** 4547** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4548** [error code] if anything goes wrong. 4549** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4550** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4551** [SQLITE_MAX_LENGTH]. 4552** ^[SQLITE_RANGE] is returned if the parameter 4553** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4554** 4555** See also: [sqlite3_bind_parameter_count()], 4556** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4557*/ 4558int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4559int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4560 void(*)(void*)); 4561int sqlite3_bind_double(sqlite3_stmt*, int, double); 4562int sqlite3_bind_int(sqlite3_stmt*, int, int); 4563int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4564int sqlite3_bind_null(sqlite3_stmt*, int); 4565int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4566int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4567int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4568 void(*)(void*), unsigned char encoding); 4569int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4570int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4571int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4572int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4573 4574/* 4575** CAPI3REF: Number Of SQL Parameters 4576** METHOD: sqlite3_stmt 4577** 4578** ^This routine can be used to find the number of [SQL parameters] 4579** in a [prepared statement]. SQL parameters are tokens of the 4580** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4581** placeholders for values that are [sqlite3_bind_blob | bound] 4582** to the parameters at a later time. 4583** 4584** ^(This routine actually returns the index of the largest (rightmost) 4585** parameter. For all forms except ?NNN, this will correspond to the 4586** number of unique parameters. If parameters of the ?NNN form are used, 4587** there may be gaps in the list.)^ 4588** 4589** See also: [sqlite3_bind_blob|sqlite3_bind()], 4590** [sqlite3_bind_parameter_name()], and 4591** [sqlite3_bind_parameter_index()]. 4592*/ 4593int sqlite3_bind_parameter_count(sqlite3_stmt*); 4594 4595/* 4596** CAPI3REF: Name Of A Host Parameter 4597** METHOD: sqlite3_stmt 4598** 4599** ^The sqlite3_bind_parameter_name(P,N) interface returns 4600** the name of the N-th [SQL parameter] in the [prepared statement] P. 4601** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4602** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4603** respectively. 4604** In other words, the initial ":" or "$" or "@" or "?" 4605** is included as part of the name.)^ 4606** ^Parameters of the form "?" without a following integer have no name 4607** and are referred to as "nameless" or "anonymous parameters". 4608** 4609** ^The first host parameter has an index of 1, not 0. 4610** 4611** ^If the value N is out of range or if the N-th parameter is 4612** nameless, then NULL is returned. ^The returned string is 4613** always in UTF-8 encoding even if the named parameter was 4614** originally specified as UTF-16 in [sqlite3_prepare16()], 4615** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4616** 4617** See also: [sqlite3_bind_blob|sqlite3_bind()], 4618** [sqlite3_bind_parameter_count()], and 4619** [sqlite3_bind_parameter_index()]. 4620*/ 4621const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4622 4623/* 4624** CAPI3REF: Index Of A Parameter With A Given Name 4625** METHOD: sqlite3_stmt 4626** 4627** ^Return the index of an SQL parameter given its name. ^The 4628** index value returned is suitable for use as the second 4629** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4630** is returned if no matching parameter is found. ^The parameter 4631** name must be given in UTF-8 even if the original statement 4632** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4633** [sqlite3_prepare16_v3()]. 4634** 4635** See also: [sqlite3_bind_blob|sqlite3_bind()], 4636** [sqlite3_bind_parameter_count()], and 4637** [sqlite3_bind_parameter_name()]. 4638*/ 4639int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4640 4641/* 4642** CAPI3REF: Reset All Bindings On A Prepared Statement 4643** METHOD: sqlite3_stmt 4644** 4645** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4646** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4647** ^Use this routine to reset all host parameters to NULL. 4648*/ 4649int sqlite3_clear_bindings(sqlite3_stmt*); 4650 4651/* 4652** CAPI3REF: Number Of Columns In A Result Set 4653** METHOD: sqlite3_stmt 4654** 4655** ^Return the number of columns in the result set returned by the 4656** [prepared statement]. ^If this routine returns 0, that means the 4657** [prepared statement] returns no data (for example an [UPDATE]). 4658** ^However, just because this routine returns a positive number does not 4659** mean that one or more rows of data will be returned. ^A SELECT statement 4660** will always have a positive sqlite3_column_count() but depending on the 4661** WHERE clause constraints and the table content, it might return no rows. 4662** 4663** See also: [sqlite3_data_count()] 4664*/ 4665int sqlite3_column_count(sqlite3_stmt *pStmt); 4666 4667/* 4668** CAPI3REF: Column Names In A Result Set 4669** METHOD: sqlite3_stmt 4670** 4671** ^These routines return the name assigned to a particular column 4672** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4673** interface returns a pointer to a zero-terminated UTF-8 string 4674** and sqlite3_column_name16() returns a pointer to a zero-terminated 4675** UTF-16 string. ^The first parameter is the [prepared statement] 4676** that implements the [SELECT] statement. ^The second parameter is the 4677** column number. ^The leftmost column is number 0. 4678** 4679** ^The returned string pointer is valid until either the [prepared statement] 4680** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4681** reprepared by the first call to [sqlite3_step()] for a particular run 4682** or until the next call to 4683** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4684** 4685** ^If sqlite3_malloc() fails during the processing of either routine 4686** (for example during a conversion from UTF-8 to UTF-16) then a 4687** NULL pointer is returned. 4688** 4689** ^The name of a result column is the value of the "AS" clause for 4690** that column, if there is an AS clause. If there is no AS clause 4691** then the name of the column is unspecified and may change from 4692** one release of SQLite to the next. 4693*/ 4694const char *sqlite3_column_name(sqlite3_stmt*, int N); 4695const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4696 4697/* 4698** CAPI3REF: Source Of Data In A Query Result 4699** METHOD: sqlite3_stmt 4700** 4701** ^These routines provide a means to determine the database, table, and 4702** table column that is the origin of a particular result column in 4703** [SELECT] statement. 4704** ^The name of the database or table or column can be returned as 4705** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4706** the database name, the _table_ routines return the table name, and 4707** the origin_ routines return the column name. 4708** ^The returned string is valid until the [prepared statement] is destroyed 4709** using [sqlite3_finalize()] or until the statement is automatically 4710** reprepared by the first call to [sqlite3_step()] for a particular run 4711** or until the same information is requested 4712** again in a different encoding. 4713** 4714** ^The names returned are the original un-aliased names of the 4715** database, table, and column. 4716** 4717** ^The first argument to these interfaces is a [prepared statement]. 4718** ^These functions return information about the Nth result column returned by 4719** the statement, where N is the second function argument. 4720** ^The left-most column is column 0 for these routines. 4721** 4722** ^If the Nth column returned by the statement is an expression or 4723** subquery and is not a column value, then all of these functions return 4724** NULL. ^These routines might also return NULL if a memory allocation error 4725** occurs. ^Otherwise, they return the name of the attached database, table, 4726** or column that query result column was extracted from. 4727** 4728** ^As with all other SQLite APIs, those whose names end with "16" return 4729** UTF-16 encoded strings and the other functions return UTF-8. 4730** 4731** ^These APIs are only available if the library was compiled with the 4732** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4733** 4734** If two or more threads call one or more 4735** [sqlite3_column_database_name | column metadata interfaces] 4736** for the same [prepared statement] and result column 4737** at the same time then the results are undefined. 4738*/ 4739const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4740const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4741const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4742const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4743const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4744const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4745 4746/* 4747** CAPI3REF: Declared Datatype Of A Query Result 4748** METHOD: sqlite3_stmt 4749** 4750** ^(The first parameter is a [prepared statement]. 4751** If this statement is a [SELECT] statement and the Nth column of the 4752** returned result set of that [SELECT] is a table column (not an 4753** expression or subquery) then the declared type of the table 4754** column is returned.)^ ^If the Nth column of the result set is an 4755** expression or subquery, then a NULL pointer is returned. 4756** ^The returned string is always UTF-8 encoded. 4757** 4758** ^(For example, given the database schema: 4759** 4760** CREATE TABLE t1(c1 VARIANT); 4761** 4762** and the following statement to be compiled: 4763** 4764** SELECT c1 + 1, c1 FROM t1; 4765** 4766** this routine would return the string "VARIANT" for the second result 4767** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4768** 4769** ^SQLite uses dynamic run-time typing. ^So just because a column 4770** is declared to contain a particular type does not mean that the 4771** data stored in that column is of the declared type. SQLite is 4772** strongly typed, but the typing is dynamic not static. ^Type 4773** is associated with individual values, not with the containers 4774** used to hold those values. 4775*/ 4776const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4777const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4778 4779/* 4780** CAPI3REF: Evaluate An SQL Statement 4781** METHOD: sqlite3_stmt 4782** 4783** After a [prepared statement] has been prepared using any of 4784** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4785** or [sqlite3_prepare16_v3()] or one of the legacy 4786** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4787** must be called one or more times to evaluate the statement. 4788** 4789** The details of the behavior of the sqlite3_step() interface depend 4790** on whether the statement was prepared using the newer "vX" interfaces 4791** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4792** [sqlite3_prepare16_v2()] or the older legacy 4793** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4794** new "vX" interface is recommended for new applications but the legacy 4795** interface will continue to be supported. 4796** 4797** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4798** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4799** ^With the "v2" interface, any of the other [result codes] or 4800** [extended result codes] might be returned as well. 4801** 4802** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4803** database locks it needs to do its job. ^If the statement is a [COMMIT] 4804** or occurs outside of an explicit transaction, then you can retry the 4805** statement. If the statement is not a [COMMIT] and occurs within an 4806** explicit transaction then you should rollback the transaction before 4807** continuing. 4808** 4809** ^[SQLITE_DONE] means that the statement has finished executing 4810** successfully. sqlite3_step() should not be called again on this virtual 4811** machine without first calling [sqlite3_reset()] to reset the virtual 4812** machine back to its initial state. 4813** 4814** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4815** is returned each time a new row of data is ready for processing by the 4816** caller. The values may be accessed using the [column access functions]. 4817** sqlite3_step() is called again to retrieve the next row of data. 4818** 4819** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4820** violation) has occurred. sqlite3_step() should not be called again on 4821** the VM. More information may be found by calling [sqlite3_errmsg()]. 4822** ^With the legacy interface, a more specific error code (for example, 4823** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4824** can be obtained by calling [sqlite3_reset()] on the 4825** [prepared statement]. ^In the "v2" interface, 4826** the more specific error code is returned directly by sqlite3_step(). 4827** 4828** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4829** Perhaps it was called on a [prepared statement] that has 4830** already been [sqlite3_finalize | finalized] or on one that had 4831** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4832** be the case that the same database connection is being used by two or 4833** more threads at the same moment in time. 4834** 4835** For all versions of SQLite up to and including 3.6.23.1, a call to 4836** [sqlite3_reset()] was required after sqlite3_step() returned anything 4837** other than [SQLITE_ROW] before any subsequent invocation of 4838** sqlite3_step(). Failure to reset the prepared statement using 4839** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4840** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4841** sqlite3_step() began 4842** calling [sqlite3_reset()] automatically in this circumstance rather 4843** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4844** break because any application that ever receives an SQLITE_MISUSE error 4845** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4846** can be used to restore the legacy behavior. 4847** 4848** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4849** API always returns a generic error code, [SQLITE_ERROR], following any 4850** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4851** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4852** specific [error codes] that better describes the error. 4853** We admit that this is a goofy design. The problem has been fixed 4854** with the "v2" interface. If you prepare all of your SQL statements 4855** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4856** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 4857** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 4858** then the more specific [error codes] are returned directly 4859** by sqlite3_step(). The use of the "vX" interfaces is recommended. 4860*/ 4861int sqlite3_step(sqlite3_stmt*); 4862 4863/* 4864** CAPI3REF: Number of columns in a result set 4865** METHOD: sqlite3_stmt 4866** 4867** ^The sqlite3_data_count(P) interface returns the number of columns in the 4868** current row of the result set of [prepared statement] P. 4869** ^If prepared statement P does not have results ready to return 4870** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 4871** interfaces) then sqlite3_data_count(P) returns 0. 4872** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 4873** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 4874** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 4875** will return non-zero if previous call to [sqlite3_step](P) returned 4876** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 4877** where it always returns zero since each step of that multi-step 4878** pragma returns 0 columns of data. 4879** 4880** See also: [sqlite3_column_count()] 4881*/ 4882int sqlite3_data_count(sqlite3_stmt *pStmt); 4883 4884/* 4885** CAPI3REF: Fundamental Datatypes 4886** KEYWORDS: SQLITE_TEXT 4887** 4888** ^(Every value in SQLite has one of five fundamental datatypes: 4889** 4890** <ul> 4891** <li> 64-bit signed integer 4892** <li> 64-bit IEEE floating point number 4893** <li> string 4894** <li> BLOB 4895** <li> NULL 4896** </ul>)^ 4897** 4898** These constants are codes for each of those types. 4899** 4900** Note that the SQLITE_TEXT constant was also used in SQLite version 2 4901** for a completely different meaning. Software that links against both 4902** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 4903** SQLITE_TEXT. 4904*/ 4905#define SQLITE_INTEGER 1 4906#define SQLITE_FLOAT 2 4907#define SQLITE_BLOB 4 4908#define SQLITE_NULL 5 4909#ifdef SQLITE_TEXT 4910# undef SQLITE_TEXT 4911#else 4912# define SQLITE_TEXT 3 4913#endif 4914#define SQLITE3_TEXT 3 4915 4916/* 4917** CAPI3REF: Result Values From A Query 4918** KEYWORDS: {column access functions} 4919** METHOD: sqlite3_stmt 4920** 4921** <b>Summary:</b> 4922** <blockquote><table border=0 cellpadding=0 cellspacing=0> 4923** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 4924** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 4925** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 4926** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 4927** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 4928** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 4929** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 4930** [sqlite3_value|unprotected sqlite3_value] object. 4931** <tr><td> <td> <td> 4932** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 4933** or a UTF-8 TEXT result in bytes 4934** <tr><td><b>sqlite3_column_bytes16 </b> 4935** <td>→ <td>Size of UTF-16 4936** TEXT in bytes 4937** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 4938** datatype of the result 4939** </table></blockquote> 4940** 4941** <b>Details:</b> 4942** 4943** ^These routines return information about a single column of the current 4944** result row of a query. ^In every case the first argument is a pointer 4945** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 4946** that was returned from [sqlite3_prepare_v2()] or one of its variants) 4947** and the second argument is the index of the column for which information 4948** should be returned. ^The leftmost column of the result set has the index 0. 4949** ^The number of columns in the result can be determined using 4950** [sqlite3_column_count()]. 4951** 4952** If the SQL statement does not currently point to a valid row, or if the 4953** column index is out of range, the result is undefined. 4954** These routines may only be called when the most recent call to 4955** [sqlite3_step()] has returned [SQLITE_ROW] and neither 4956** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 4957** If any of these routines are called after [sqlite3_reset()] or 4958** [sqlite3_finalize()] or after [sqlite3_step()] has returned 4959** something other than [SQLITE_ROW], the results are undefined. 4960** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 4961** are called from a different thread while any of these routines 4962** are pending, then the results are undefined. 4963** 4964** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 4965** each return the value of a result column in a specific data format. If 4966** the result column is not initially in the requested format (for example, 4967** if the query returns an integer but the sqlite3_column_text() interface 4968** is used to extract the value) then an automatic type conversion is performed. 4969** 4970** ^The sqlite3_column_type() routine returns the 4971** [SQLITE_INTEGER | datatype code] for the initial data type 4972** of the result column. ^The returned value is one of [SQLITE_INTEGER], 4973** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 4974** The return value of sqlite3_column_type() can be used to decide which 4975** of the first six interface should be used to extract the column value. 4976** The value returned by sqlite3_column_type() is only meaningful if no 4977** automatic type conversions have occurred for the value in question. 4978** After a type conversion, the result of calling sqlite3_column_type() 4979** is undefined, though harmless. Future 4980** versions of SQLite may change the behavior of sqlite3_column_type() 4981** following a type conversion. 4982** 4983** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 4984** or sqlite3_column_bytes16() interfaces can be used to determine the size 4985** of that BLOB or string. 4986** 4987** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 4988** routine returns the number of bytes in that BLOB or string. 4989** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 4990** the string to UTF-8 and then returns the number of bytes. 4991** ^If the result is a numeric value then sqlite3_column_bytes() uses 4992** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 4993** the number of bytes in that string. 4994** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 4995** 4996** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 4997** routine returns the number of bytes in that BLOB or string. 4998** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 4999** the string to UTF-16 and then returns the number of bytes. 5000** ^If the result is a numeric value then sqlite3_column_bytes16() uses 5001** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 5002** the number of bytes in that string. 5003** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 5004** 5005** ^The values returned by [sqlite3_column_bytes()] and 5006** [sqlite3_column_bytes16()] do not include the zero terminators at the end 5007** of the string. ^For clarity: the values returned by 5008** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 5009** bytes in the string, not the number of characters. 5010** 5011** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 5012** even empty strings, are always zero-terminated. ^The return 5013** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 5014** 5015** ^Strings returned by sqlite3_column_text16() always have the endianness 5016** which is native to the platform, regardless of the text encoding set 5017** for the database. 5018** 5019** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 5020** [unprotected sqlite3_value] object. In a multithreaded environment, 5021** an unprotected sqlite3_value object may only be used safely with 5022** [sqlite3_bind_value()] and [sqlite3_result_value()]. 5023** If the [unprotected sqlite3_value] object returned by 5024** [sqlite3_column_value()] is used in any other way, including calls 5025** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 5026** or [sqlite3_value_bytes()], the behavior is not threadsafe. 5027** Hence, the sqlite3_column_value() interface 5028** is normally only useful within the implementation of 5029** [application-defined SQL functions] or [virtual tables], not within 5030** top-level application code. 5031** 5032** These routines may attempt to convert the datatype of the result. 5033** ^For example, if the internal representation is FLOAT and a text result 5034** is requested, [sqlite3_snprintf()] is used internally to perform the 5035** conversion automatically. ^(The following table details the conversions 5036** that are applied: 5037** 5038** <blockquote> 5039** <table border="1"> 5040** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 5041** 5042** <tr><td> NULL <td> INTEGER <td> Result is 0 5043** <tr><td> NULL <td> FLOAT <td> Result is 0.0 5044** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 5045** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 5046** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 5047** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 5048** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 5049** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 5050** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 5051** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 5052** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 5053** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 5054** <tr><td> TEXT <td> BLOB <td> No change 5055** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 5056** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 5057** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator 5058** </table> 5059** </blockquote>)^ 5060** 5061** Note that when type conversions occur, pointers returned by prior 5062** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 5063** sqlite3_column_text16() may be invalidated. 5064** Type conversions and pointer invalidations might occur 5065** in the following cases: 5066** 5067** <ul> 5068** <li> The initial content is a BLOB and sqlite3_column_text() or 5069** sqlite3_column_text16() is called. A zero-terminator might 5070** need to be added to the string.</li> 5071** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 5072** sqlite3_column_text16() is called. The content must be converted 5073** to UTF-16.</li> 5074** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 5075** sqlite3_column_text() is called. The content must be converted 5076** to UTF-8.</li> 5077** </ul> 5078** 5079** ^Conversions between UTF-16be and UTF-16le are always done in place and do 5080** not invalidate a prior pointer, though of course the content of the buffer 5081** that the prior pointer references will have been modified. Other kinds 5082** of conversion are done in place when it is possible, but sometimes they 5083** are not possible and in those cases prior pointers are invalidated. 5084** 5085** The safest policy is to invoke these routines 5086** in one of the following ways: 5087** 5088** <ul> 5089** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 5090** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 5091** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 5092** </ul> 5093** 5094** In other words, you should call sqlite3_column_text(), 5095** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 5096** into the desired format, then invoke sqlite3_column_bytes() or 5097** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 5098** to sqlite3_column_text() or sqlite3_column_blob() with calls to 5099** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 5100** with calls to sqlite3_column_bytes(). 5101** 5102** ^The pointers returned are valid until a type conversion occurs as 5103** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 5104** [sqlite3_finalize()] is called. ^The memory space used to hold strings 5105** and BLOBs is freed automatically. Do not pass the pointers returned 5106** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 5107** [sqlite3_free()]. 5108** 5109** As long as the input parameters are correct, these routines will only 5110** fail if an out-of-memory error occurs during a format conversion. 5111** Only the following subset of interfaces are subject to out-of-memory 5112** errors: 5113** 5114** <ul> 5115** <li> sqlite3_column_blob() 5116** <li> sqlite3_column_text() 5117** <li> sqlite3_column_text16() 5118** <li> sqlite3_column_bytes() 5119** <li> sqlite3_column_bytes16() 5120** </ul> 5121** 5122** If an out-of-memory error occurs, then the return value from these 5123** routines is the same as if the column had contained an SQL NULL value. 5124** Valid SQL NULL returns can be distinguished from out-of-memory errors 5125** by invoking the [sqlite3_errcode()] immediately after the suspect 5126** return value is obtained and before any 5127** other SQLite interface is called on the same [database connection]. 5128*/ 5129const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 5130double sqlite3_column_double(sqlite3_stmt*, int iCol); 5131int sqlite3_column_int(sqlite3_stmt*, int iCol); 5132sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 5133const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 5134const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 5135sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 5136int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 5137int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 5138int sqlite3_column_type(sqlite3_stmt*, int iCol); 5139 5140/* 5141** CAPI3REF: Destroy A Prepared Statement Object 5142** DESTRUCTOR: sqlite3_stmt 5143** 5144** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 5145** ^If the most recent evaluation of the statement encountered no errors 5146** or if the statement is never been evaluated, then sqlite3_finalize() returns 5147** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 5148** sqlite3_finalize(S) returns the appropriate [error code] or 5149** [extended error code]. 5150** 5151** ^The sqlite3_finalize(S) routine can be called at any point during 5152** the life cycle of [prepared statement] S: 5153** before statement S is ever evaluated, after 5154** one or more calls to [sqlite3_reset()], or after any call 5155** to [sqlite3_step()] regardless of whether or not the statement has 5156** completed execution. 5157** 5158** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5159** 5160** The application must finalize every [prepared statement] in order to avoid 5161** resource leaks. It is a grievous error for the application to try to use 5162** a prepared statement after it has been finalized. Any use of a prepared 5163** statement after it has been finalized can result in undefined and 5164** undesirable behavior such as segfaults and heap corruption. 5165*/ 5166int sqlite3_finalize(sqlite3_stmt *pStmt); 5167 5168/* 5169** CAPI3REF: Reset A Prepared Statement Object 5170** METHOD: sqlite3_stmt 5171** 5172** The sqlite3_reset() function is called to reset a [prepared statement] 5173** object back to its initial state, ready to be re-executed. 5174** ^Any SQL statement variables that had values bound to them using 5175** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5176** Use [sqlite3_clear_bindings()] to reset the bindings. 5177** 5178** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5179** back to the beginning of its program. 5180** 5181** ^If the most recent call to [sqlite3_step(S)] for the 5182** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 5183** or if [sqlite3_step(S)] has never before been called on S, 5184** then [sqlite3_reset(S)] returns [SQLITE_OK]. 5185** 5186** ^If the most recent call to [sqlite3_step(S)] for the 5187** [prepared statement] S indicated an error, then 5188** [sqlite3_reset(S)] returns an appropriate [error code]. 5189** 5190** ^The [sqlite3_reset(S)] interface does not change the values 5191** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5192*/ 5193int sqlite3_reset(sqlite3_stmt *pStmt); 5194 5195/* 5196** CAPI3REF: Create Or Redefine SQL Functions 5197** KEYWORDS: {function creation routines} 5198** METHOD: sqlite3 5199** 5200** ^These functions (collectively known as "function creation routines") 5201** are used to add SQL functions or aggregates or to redefine the behavior 5202** of existing SQL functions or aggregates. The only differences between 5203** the three "sqlite3_create_function*" routines are the text encoding 5204** expected for the second parameter (the name of the function being 5205** created) and the presence or absence of a destructor callback for 5206** the application data pointer. Function sqlite3_create_window_function() 5207** is similar, but allows the user to supply the extra callback functions 5208** needed by [aggregate window functions]. 5209** 5210** ^The first parameter is the [database connection] to which the SQL 5211** function is to be added. ^If an application uses more than one database 5212** connection then application-defined SQL functions must be added 5213** to each database connection separately. 5214** 5215** ^The second parameter is the name of the SQL function to be created or 5216** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5217** representation, exclusive of the zero-terminator. ^Note that the name 5218** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5219** ^Any attempt to create a function with a longer name 5220** will result in [SQLITE_MISUSE] being returned. 5221** 5222** ^The third parameter (nArg) 5223** is the number of arguments that the SQL function or 5224** aggregate takes. ^If this parameter is -1, then the SQL function or 5225** aggregate may take any number of arguments between 0 and the limit 5226** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5227** parameter is less than -1 or greater than 127 then the behavior is 5228** undefined. 5229** 5230** ^The fourth parameter, eTextRep, specifies what 5231** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5232** its parameters. The application should set this parameter to 5233** [SQLITE_UTF16LE] if the function implementation invokes 5234** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5235** implementation invokes [sqlite3_value_text16be()] on an input, or 5236** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5237** otherwise. ^The same SQL function may be registered multiple times using 5238** different preferred text encodings, with different implementations for 5239** each encoding. 5240** ^When multiple implementations of the same function are available, SQLite 5241** will pick the one that involves the least amount of data conversion. 5242** 5243** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5244** to signal that the function will always return the same result given 5245** the same inputs within a single SQL statement. Most SQL functions are 5246** deterministic. The built-in [random()] SQL function is an example of a 5247** function that is not deterministic. The SQLite query planner is able to 5248** perform additional optimizations on deterministic functions, so use 5249** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5250** 5251** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5252** flag, which if present prevents the function from being invoked from 5253** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5254** index expressions, or the WHERE clause of partial indexes. 5255** 5256** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5257** all application-defined SQL functions that do not need to be 5258** used inside of triggers, view, CHECK constraints, or other elements of 5259** the database schema. This flags is especially recommended for SQL 5260** functions that have side effects or reveal internal application state. 5261** Without this flag, an attacker might be able to modify the schema of 5262** a database file to include invocations of the function with parameters 5263** chosen by the attacker, which the application will then execute when 5264** the database file is opened and read. 5265** 5266** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5267** function can gain access to this pointer using [sqlite3_user_data()].)^ 5268** 5269** ^The sixth, seventh and eighth parameters passed to the three 5270** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5271** pointers to C-language functions that implement the SQL function or 5272** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5273** callback only; NULL pointers must be passed as the xStep and xFinal 5274** parameters. ^An aggregate SQL function requires an implementation of xStep 5275** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5276** SQL function or aggregate, pass NULL pointers for all three function 5277** callbacks. 5278** 5279** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5280** and xInverse) passed to sqlite3_create_window_function are pointers to 5281** C-language callbacks that implement the new function. xStep and xFinal 5282** must both be non-NULL. xValue and xInverse may either both be NULL, in 5283** which case a regular aggregate function is created, or must both be 5284** non-NULL, in which case the new function may be used as either an aggregate 5285** or aggregate window function. More details regarding the implementation 5286** of aggregate window functions are 5287** [user-defined window functions|available here]. 5288** 5289** ^(If the final parameter to sqlite3_create_function_v2() or 5290** sqlite3_create_window_function() is not NULL, then it is destructor for 5291** the application data pointer. The destructor is invoked when the function 5292** is deleted, either by being overloaded or when the database connection 5293** closes.)^ ^The destructor is also invoked if the call to 5294** sqlite3_create_function_v2() fails. ^When the destructor callback is 5295** invoked, it is passed a single argument which is a copy of the application 5296** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5297** 5298** ^It is permitted to register multiple implementations of the same 5299** functions with the same name but with either differing numbers of 5300** arguments or differing preferred text encodings. ^SQLite will use 5301** the implementation that most closely matches the way in which the 5302** SQL function is used. ^A function implementation with a non-negative 5303** nArg parameter is a better match than a function implementation with 5304** a negative nArg. ^A function where the preferred text encoding 5305** matches the database encoding is a better 5306** match than a function where the encoding is different. 5307** ^A function where the encoding difference is between UTF16le and UTF16be 5308** is a closer match than a function where the encoding difference is 5309** between UTF8 and UTF16. 5310** 5311** ^Built-in functions may be overloaded by new application-defined functions. 5312** 5313** ^An application-defined function is permitted to call other 5314** SQLite interfaces. However, such calls must not 5315** close the database connection nor finalize or reset the prepared 5316** statement in which the function is running. 5317*/ 5318int sqlite3_create_function( 5319 sqlite3 *db, 5320 const char *zFunctionName, 5321 int nArg, 5322 int eTextRep, 5323 void *pApp, 5324 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5325 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5326 void (*xFinal)(sqlite3_context*) 5327); 5328int sqlite3_create_function16( 5329 sqlite3 *db, 5330 const void *zFunctionName, 5331 int nArg, 5332 int eTextRep, 5333 void *pApp, 5334 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5335 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5336 void (*xFinal)(sqlite3_context*) 5337); 5338int sqlite3_create_function_v2( 5339 sqlite3 *db, 5340 const char *zFunctionName, 5341 int nArg, 5342 int eTextRep, 5343 void *pApp, 5344 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5345 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5346 void (*xFinal)(sqlite3_context*), 5347 void(*xDestroy)(void*) 5348); 5349int sqlite3_create_window_function( 5350 sqlite3 *db, 5351 const char *zFunctionName, 5352 int nArg, 5353 int eTextRep, 5354 void *pApp, 5355 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5356 void (*xFinal)(sqlite3_context*), 5357 void (*xValue)(sqlite3_context*), 5358 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5359 void(*xDestroy)(void*) 5360); 5361 5362/* 5363** CAPI3REF: Text Encodings 5364** 5365** These constant define integer codes that represent the various 5366** text encodings supported by SQLite. 5367*/ 5368#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5369#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5370#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5371#define SQLITE_UTF16 4 /* Use native byte order */ 5372#define SQLITE_ANY 5 /* Deprecated */ 5373#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5374 5375/* 5376** CAPI3REF: Function Flags 5377** 5378** These constants may be ORed together with the 5379** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5380** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5381** [sqlite3_create_function_v2()]. 5382** 5383** <dl> 5384** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5385** The SQLITE_DETERMINISTIC flag means that the new function always gives 5386** the same output when the input parameters are the same. 5387** The [abs|abs() function] is deterministic, for example, but 5388** [randomblob|randomblob()] is not. Functions must 5389** be deterministic in order to be used in certain contexts such as 5390** with the WHERE clause of [partial indexes] or in [generated columns]. 5391** SQLite might also optimize deterministic functions by factoring them 5392** out of inner loops. 5393** </dd> 5394** 5395** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5396** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5397** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5398** schema structures such as [CHECK constraints], [DEFAULT clauses], 5399** [expression indexes], [partial indexes], or [generated columns]. 5400** The SQLITE_DIRECTONLY flags is a security feature which is recommended 5401** for all [application-defined SQL functions], and especially for functions 5402** that have side-effects or that could potentially leak sensitive 5403** information. 5404** </dd> 5405** 5406** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5407** The SQLITE_INNOCUOUS flag means that the function is unlikely 5408** to cause problems even if misused. An innocuous function should have 5409** no side effects and should not depend on any values other than its 5410** input parameters. The [abs|abs() function] is an example of an 5411** innocuous function. 5412** The [load_extension() SQL function] is not innocuous because of its 5413** side effects. 5414** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5415** exactly the same. The [random|random() function] is an example of a 5416** function that is innocuous but not deterministic. 5417** <p>Some heightened security settings 5418** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5419** disable the use of SQL functions inside views and triggers and in 5420** schema structures such as [CHECK constraints], [DEFAULT clauses], 5421** [expression indexes], [partial indexes], and [generated columns] unless 5422** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5423** are innocuous. Developers are advised to avoid using the 5424** SQLITE_INNOCUOUS flag for application-defined functions unless the 5425** function has been carefully audited and found to be free of potentially 5426** security-adverse side-effects and information-leaks. 5427** </dd> 5428** 5429** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5430** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call 5431** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5432** Specifying this flag makes no difference for scalar or aggregate user 5433** functions. However, if it is not specified for a user-defined window 5434** function, then any sub-types belonging to arguments passed to the window 5435** function may be discarded before the window function is called (i.e. 5436** sqlite3_value_subtype() will always return 0). 5437** </dd> 5438** </dl> 5439*/ 5440#define SQLITE_DETERMINISTIC 0x000000800 5441#define SQLITE_DIRECTONLY 0x000080000 5442#define SQLITE_SUBTYPE 0x000100000 5443#define SQLITE_INNOCUOUS 0x000200000 5444 5445/* 5446** CAPI3REF: Deprecated Functions 5447** DEPRECATED 5448** 5449** These functions are [deprecated]. In order to maintain 5450** backwards compatibility with older code, these functions continue 5451** to be supported. However, new applications should avoid 5452** the use of these functions. To encourage programmers to avoid 5453** these functions, we will not explain what they do. 5454*/ 5455#ifndef SQLITE_OMIT_DEPRECATED 5456SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5457SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5458SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5459SQLITE_DEPRECATED int sqlite3_global_recover(void); 5460SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5461SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5462 void*,sqlite3_int64); 5463#endif 5464 5465/* 5466** CAPI3REF: Obtaining SQL Values 5467** METHOD: sqlite3_value 5468** 5469** <b>Summary:</b> 5470** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5471** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5472** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5473** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5474** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5475** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5476** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5477** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5478** the native byteorder 5479** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5480** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5481** <tr><td> <td> <td> 5482** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5483** or a UTF-8 TEXT in bytes 5484** <tr><td><b>sqlite3_value_bytes16 </b> 5485** <td>→ <td>Size of UTF-16 5486** TEXT in bytes 5487** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5488** datatype of the value 5489** <tr><td><b>sqlite3_value_numeric_type </b> 5490** <td>→ <td>Best numeric datatype of the value 5491** <tr><td><b>sqlite3_value_nochange </b> 5492** <td>→ <td>True if the column is unchanged in an UPDATE 5493** against a virtual table. 5494** <tr><td><b>sqlite3_value_frombind </b> 5495** <td>→ <td>True if value originated from a [bound parameter] 5496** </table></blockquote> 5497** 5498** <b>Details:</b> 5499** 5500** These routines extract type, size, and content information from 5501** [protected sqlite3_value] objects. Protected sqlite3_value objects 5502** are used to pass parameter information into the functions that 5503** implement [application-defined SQL functions] and [virtual tables]. 5504** 5505** These routines work only with [protected sqlite3_value] objects. 5506** Any attempt to use these routines on an [unprotected sqlite3_value] 5507** is not threadsafe. 5508** 5509** ^These routines work just like the corresponding [column access functions] 5510** except that these routines take a single [protected sqlite3_value] object 5511** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5512** 5513** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5514** in the native byte-order of the host machine. ^The 5515** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5516** extract UTF-16 strings as big-endian and little-endian respectively. 5517** 5518** ^If [sqlite3_value] object V was initialized 5519** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5520** and if X and Y are strings that compare equal according to strcmp(X,Y), 5521** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5522** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5523** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5524** 5525** ^(The sqlite3_value_type(V) interface returns the 5526** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5527** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5528** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5529** Other interfaces might change the datatype for an sqlite3_value object. 5530** For example, if the datatype is initially SQLITE_INTEGER and 5531** sqlite3_value_text(V) is called to extract a text value for that 5532** integer, then subsequent calls to sqlite3_value_type(V) might return 5533** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5534** occurs is undefined and may change from one release of SQLite to the next. 5535** 5536** ^(The sqlite3_value_numeric_type() interface attempts to apply 5537** numeric affinity to the value. This means that an attempt is 5538** made to convert the value to an integer or floating point. If 5539** such a conversion is possible without loss of information (in other 5540** words, if the value is a string that looks like a number) 5541** then the conversion is performed. Otherwise no conversion occurs. 5542** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5543** 5544** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8], 5545** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current encoding 5546** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X) 5547** returns something other than SQLITE_TEXT, then the return value from 5548** sqlite3_value_encoding(X) is meaningless. ^Calls to 5549** sqlite3_value_text(X), sqlite3_value_text16(X), sqlite3_value_text16be(X), 5550** sqlite3_value_text16le(X), sqlite3_value_bytes(X), or 5551** sqlite3_value_bytes16(X) might change the encoding of the value X and 5552** thus change the return from subsequent calls to sqlite3_value_encoding(X). 5553** 5554** ^Within the [xUpdate] method of a [virtual table], the 5555** sqlite3_value_nochange(X) interface returns true if and only if 5556** the column corresponding to X is unchanged by the UPDATE operation 5557** that the xUpdate method call was invoked to implement and if 5558** and the prior [xColumn] method call that was invoked to extracted 5559** the value for that column returned without setting a result (probably 5560** because it queried [sqlite3_vtab_nochange()] and found that the column 5561** was unchanging). ^Within an [xUpdate] method, any value for which 5562** sqlite3_value_nochange(X) is true will in all other respects appear 5563** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5564** than within an [xUpdate] method call for an UPDATE statement, then 5565** the return value is arbitrary and meaningless. 5566** 5567** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5568** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5569** interfaces. ^If X comes from an SQL literal value, or a table column, 5570** or an expression, then sqlite3_value_frombind(X) returns zero. 5571** 5572** Please pay particular attention to the fact that the pointer returned 5573** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5574** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5575** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5576** or [sqlite3_value_text16()]. 5577** 5578** These routines must be called from the same thread as 5579** the SQL function that supplied the [sqlite3_value*] parameters. 5580** 5581** As long as the input parameter is correct, these routines can only 5582** fail if an out-of-memory error occurs during a format conversion. 5583** Only the following subset of interfaces are subject to out-of-memory 5584** errors: 5585** 5586** <ul> 5587** <li> sqlite3_value_blob() 5588** <li> sqlite3_value_text() 5589** <li> sqlite3_value_text16() 5590** <li> sqlite3_value_text16le() 5591** <li> sqlite3_value_text16be() 5592** <li> sqlite3_value_bytes() 5593** <li> sqlite3_value_bytes16() 5594** </ul> 5595** 5596** If an out-of-memory error occurs, then the return value from these 5597** routines is the same as if the column had contained an SQL NULL value. 5598** Valid SQL NULL returns can be distinguished from out-of-memory errors 5599** by invoking the [sqlite3_errcode()] immediately after the suspect 5600** return value is obtained and before any 5601** other SQLite interface is called on the same [database connection]. 5602*/ 5603const void *sqlite3_value_blob(sqlite3_value*); 5604double sqlite3_value_double(sqlite3_value*); 5605int sqlite3_value_int(sqlite3_value*); 5606sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5607void *sqlite3_value_pointer(sqlite3_value*, const char*); 5608const unsigned char *sqlite3_value_text(sqlite3_value*); 5609const void *sqlite3_value_text16(sqlite3_value*); 5610const void *sqlite3_value_text16le(sqlite3_value*); 5611const void *sqlite3_value_text16be(sqlite3_value*); 5612int sqlite3_value_bytes(sqlite3_value*); 5613int sqlite3_value_bytes16(sqlite3_value*); 5614int sqlite3_value_type(sqlite3_value*); 5615int sqlite3_value_numeric_type(sqlite3_value*); 5616int sqlite3_value_nochange(sqlite3_value*); 5617int sqlite3_value_frombind(sqlite3_value*); 5618int sqlite3_value_encoding(sqlite3_value*); 5619 5620/* 5621** CAPI3REF: Finding The Subtype Of SQL Values 5622** METHOD: sqlite3_value 5623** 5624** The sqlite3_value_subtype(V) function returns the subtype for 5625** an [application-defined SQL function] argument V. The subtype 5626** information can be used to pass a limited amount of context from 5627** one SQL function to another. Use the [sqlite3_result_subtype()] 5628** routine to set the subtype for the return value of an SQL function. 5629*/ 5630unsigned int sqlite3_value_subtype(sqlite3_value*); 5631 5632/* 5633** CAPI3REF: Copy And Free SQL Values 5634** METHOD: sqlite3_value 5635** 5636** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5637** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5638** is a [protected sqlite3_value] object even if the input is not. 5639** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5640** memory allocation fails. ^If V is a [pointer value], then the result 5641** of sqlite3_value_dup(V) is a NULL value. 5642** 5643** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5644** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5645** then sqlite3_value_free(V) is a harmless no-op. 5646*/ 5647sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5648void sqlite3_value_free(sqlite3_value*); 5649 5650/* 5651** CAPI3REF: Obtain Aggregate Function Context 5652** METHOD: sqlite3_context 5653** 5654** Implementations of aggregate SQL functions use this 5655** routine to allocate memory for storing their state. 5656** 5657** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5658** for a particular aggregate function, SQLite allocates 5659** N bytes of memory, zeroes out that memory, and returns a pointer 5660** to the new memory. ^On second and subsequent calls to 5661** sqlite3_aggregate_context() for the same aggregate function instance, 5662** the same buffer is returned. Sqlite3_aggregate_context() is normally 5663** called once for each invocation of the xStep callback and then one 5664** last time when the xFinal callback is invoked. ^(When no rows match 5665** an aggregate query, the xStep() callback of the aggregate function 5666** implementation is never called and xFinal() is called exactly once. 5667** In those cases, sqlite3_aggregate_context() might be called for the 5668** first time from within xFinal().)^ 5669** 5670** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5671** when first called if N is less than or equal to zero or if a memory 5672** allocation error occurs. 5673** 5674** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5675** determined by the N parameter on first successful call. Changing the 5676** value of N in any subsequent call to sqlite3_aggregate_context() within 5677** the same aggregate function instance will not resize the memory 5678** allocation.)^ Within the xFinal callback, it is customary to set 5679** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5680** pointless memory allocations occur. 5681** 5682** ^SQLite automatically frees the memory allocated by 5683** sqlite3_aggregate_context() when the aggregate query concludes. 5684** 5685** The first parameter must be a copy of the 5686** [sqlite3_context | SQL function context] that is the first parameter 5687** to the xStep or xFinal callback routine that implements the aggregate 5688** function. 5689** 5690** This routine must be called from the same thread in which 5691** the aggregate SQL function is running. 5692*/ 5693void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5694 5695/* 5696** CAPI3REF: User Data For Functions 5697** METHOD: sqlite3_context 5698** 5699** ^The sqlite3_user_data() interface returns a copy of 5700** the pointer that was the pUserData parameter (the 5th parameter) 5701** of the [sqlite3_create_function()] 5702** and [sqlite3_create_function16()] routines that originally 5703** registered the application defined function. 5704** 5705** This routine must be called from the same thread in which 5706** the application-defined function is running. 5707*/ 5708void *sqlite3_user_data(sqlite3_context*); 5709 5710/* 5711** CAPI3REF: Database Connection For Functions 5712** METHOD: sqlite3_context 5713** 5714** ^The sqlite3_context_db_handle() interface returns a copy of 5715** the pointer to the [database connection] (the 1st parameter) 5716** of the [sqlite3_create_function()] 5717** and [sqlite3_create_function16()] routines that originally 5718** registered the application defined function. 5719*/ 5720sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5721 5722/* 5723** CAPI3REF: Function Auxiliary Data 5724** METHOD: sqlite3_context 5725** 5726** These functions may be used by (non-aggregate) SQL functions to 5727** associate metadata with argument values. If the same value is passed to 5728** multiple invocations of the same SQL function during query execution, under 5729** some circumstances the associated metadata may be preserved. An example 5730** of where this might be useful is in a regular-expression matching 5731** function. The compiled version of the regular expression can be stored as 5732** metadata associated with the pattern string. 5733** Then as long as the pattern string remains the same, 5734** the compiled regular expression can be reused on multiple 5735** invocations of the same function. 5736** 5737** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata 5738** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5739** value to the application-defined function. ^N is zero for the left-most 5740** function argument. ^If there is no metadata 5741** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5742** returns a NULL pointer. 5743** 5744** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 5745** argument of the application-defined function. ^Subsequent 5746** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5747** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 5748** NULL if the metadata has been discarded. 5749** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5750** SQLite will invoke the destructor function X with parameter P exactly 5751** once, when the metadata is discarded. 5752** SQLite is free to discard the metadata at any time, including: <ul> 5753** <li> ^(when the corresponding function parameter changes)^, or 5754** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5755** SQL statement)^, or 5756** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5757** parameter)^, or 5758** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5759** allocation error occurs.)^ </ul> 5760** 5761** Note the last bullet in particular. The destructor X in 5762** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5763** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5764** should be called near the end of the function implementation and the 5765** function implementation should not make any use of P after 5766** sqlite3_set_auxdata() has been called. 5767** 5768** ^(In practice, metadata is preserved between function calls for 5769** function parameters that are compile-time constants, including literal 5770** values and [parameters] and expressions composed from the same.)^ 5771** 5772** The value of the N parameter to these interfaces should be non-negative. 5773** Future enhancements may make use of negative N values to define new 5774** kinds of function caching behavior. 5775** 5776** These routines must be called from the same thread in which 5777** the SQL function is running. 5778*/ 5779void *sqlite3_get_auxdata(sqlite3_context*, int N); 5780void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5781 5782 5783/* 5784** CAPI3REF: Constants Defining Special Destructor Behavior 5785** 5786** These are special values for the destructor that is passed in as the 5787** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 5788** argument is SQLITE_STATIC, it means that the content pointer is constant 5789** and will never change. It does not need to be destroyed. ^The 5790** SQLITE_TRANSIENT value means that the content will likely change in 5791** the near future and that SQLite should make its own private copy of 5792** the content before returning. 5793** 5794** The typedef is necessary to work around problems in certain 5795** C++ compilers. 5796*/ 5797typedef void (*sqlite3_destructor_type)(void*); 5798#define SQLITE_STATIC ((sqlite3_destructor_type)0) 5799#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 5800 5801/* 5802** CAPI3REF: Setting The Result Of An SQL Function 5803** METHOD: sqlite3_context 5804** 5805** These routines are used by the xFunc or xFinal callbacks that 5806** implement SQL functions and aggregates. See 5807** [sqlite3_create_function()] and [sqlite3_create_function16()] 5808** for additional information. 5809** 5810** These functions work very much like the [parameter binding] family of 5811** functions used to bind values to host parameters in prepared statements. 5812** Refer to the [SQL parameter] documentation for additional information. 5813** 5814** ^The sqlite3_result_blob() interface sets the result from 5815** an application-defined function to be the BLOB whose content is pointed 5816** to by the second parameter and which is N bytes long where N is the 5817** third parameter. 5818** 5819** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 5820** interfaces set the result of the application-defined function to be 5821** a BLOB containing all zero bytes and N bytes in size. 5822** 5823** ^The sqlite3_result_double() interface sets the result from 5824** an application-defined function to be a floating point value specified 5825** by its 2nd argument. 5826** 5827** ^The sqlite3_result_error() and sqlite3_result_error16() functions 5828** cause the implemented SQL function to throw an exception. 5829** ^SQLite uses the string pointed to by the 5830** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 5831** as the text of an error message. ^SQLite interprets the error 5832** message string from sqlite3_result_error() as UTF-8. ^SQLite 5833** interprets the string from sqlite3_result_error16() as UTF-16 using 5834** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 5835** ^If the third parameter to sqlite3_result_error() 5836** or sqlite3_result_error16() is negative then SQLite takes as the error 5837** message all text up through the first zero character. 5838** ^If the third parameter to sqlite3_result_error() or 5839** sqlite3_result_error16() is non-negative then SQLite takes that many 5840** bytes (not characters) from the 2nd parameter as the error message. 5841** ^The sqlite3_result_error() and sqlite3_result_error16() 5842** routines make a private copy of the error message text before 5843** they return. Hence, the calling function can deallocate or 5844** modify the text after they return without harm. 5845** ^The sqlite3_result_error_code() function changes the error code 5846** returned by SQLite as a result of an error in a function. ^By default, 5847** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 5848** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 5849** 5850** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 5851** error indicating that a string or BLOB is too long to represent. 5852** 5853** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 5854** error indicating that a memory allocation failed. 5855** 5856** ^The sqlite3_result_int() interface sets the return value 5857** of the application-defined function to be the 32-bit signed integer 5858** value given in the 2nd argument. 5859** ^The sqlite3_result_int64() interface sets the return value 5860** of the application-defined function to be the 64-bit signed integer 5861** value given in the 2nd argument. 5862** 5863** ^The sqlite3_result_null() interface sets the return value 5864** of the application-defined function to be NULL. 5865** 5866** ^The sqlite3_result_text(), sqlite3_result_text16(), 5867** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 5868** set the return value of the application-defined function to be 5869** a text string which is represented as UTF-8, UTF-16 native byte order, 5870** UTF-16 little endian, or UTF-16 big endian, respectively. 5871** ^The sqlite3_result_text64() interface sets the return value of an 5872** application-defined function to be a text string in an encoding 5873** specified by the fifth (and last) parameter, which must be one 5874** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 5875** ^SQLite takes the text result from the application from 5876** the 2nd parameter of the sqlite3_result_text* interfaces. 5877** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5878** is negative, then SQLite takes result text from the 2nd parameter 5879** through the first zero character. 5880** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5881** is non-negative, then as many bytes (not characters) of the text 5882** pointed to by the 2nd parameter are taken as the application-defined 5883** function result. If the 3rd parameter is non-negative, then it 5884** must be the byte offset into the string where the NUL terminator would 5885** appear if the string where NUL terminated. If any NUL characters occur 5886** in the string at a byte offset that is less than the value of the 3rd 5887** parameter, then the resulting string will contain embedded NULs and the 5888** result of expressions operating on strings with embedded NULs is undefined. 5889** ^If the 4th parameter to the sqlite3_result_text* interfaces 5890** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 5891** function as the destructor on the text or BLOB result when it has 5892** finished using that result. 5893** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 5894** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 5895** assumes that the text or BLOB result is in constant space and does not 5896** copy the content of the parameter nor call a destructor on the content 5897** when it has finished using that result. 5898** ^If the 4th parameter to the sqlite3_result_text* interfaces 5899** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 5900** then SQLite makes a copy of the result into space obtained 5901** from [sqlite3_malloc()] before it returns. 5902** 5903** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 5904** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 5905** when the encoding is not UTF8, if the input UTF16 begins with a 5906** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 5907** string and the rest of the string is interpreted according to the 5908** byte-order specified by the BOM. ^The byte-order specified by 5909** the BOM at the beginning of the text overrides the byte-order 5910** specified by the interface procedure. ^So, for example, if 5911** sqlite3_result_text16le() is invoked with text that begins 5912** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 5913** first two bytes of input are skipped and the remaining input 5914** is interpreted as UTF16BE text. 5915** 5916** ^For UTF16 input text to the sqlite3_result_text16(), 5917** sqlite3_result_text16be(), sqlite3_result_text16le(), and 5918** sqlite3_result_text64() routines, if the text contains invalid 5919** UTF16 characters, the invalid characters might be converted 5920** into the unicode replacement character, U+FFFD. 5921** 5922** ^The sqlite3_result_value() interface sets the result of 5923** the application-defined function to be a copy of the 5924** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 5925** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 5926** so that the [sqlite3_value] specified in the parameter may change or 5927** be deallocated after sqlite3_result_value() returns without harm. 5928** ^A [protected sqlite3_value] object may always be used where an 5929** [unprotected sqlite3_value] object is required, so either 5930** kind of [sqlite3_value] object can be used with this interface. 5931** 5932** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 5933** SQL NULL value, just like [sqlite3_result_null(C)], except that it 5934** also associates the host-language pointer P or type T with that 5935** NULL value such that the pointer can be retrieved within an 5936** [application-defined SQL function] using [sqlite3_value_pointer()]. 5937** ^If the D parameter is not NULL, then it is a pointer to a destructor 5938** for the P parameter. ^SQLite invokes D with P as its only argument 5939** when SQLite is finished with P. The T parameter should be a static 5940** string and preferably a string literal. The sqlite3_result_pointer() 5941** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5942** 5943** If these routines are called from within the different thread 5944** than the one containing the application-defined function that received 5945** the [sqlite3_context] pointer, the results are undefined. 5946*/ 5947void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 5948void sqlite3_result_blob64(sqlite3_context*,const void*, 5949 sqlite3_uint64,void(*)(void*)); 5950void sqlite3_result_double(sqlite3_context*, double); 5951void sqlite3_result_error(sqlite3_context*, const char*, int); 5952void sqlite3_result_error16(sqlite3_context*, const void*, int); 5953void sqlite3_result_error_toobig(sqlite3_context*); 5954void sqlite3_result_error_nomem(sqlite3_context*); 5955void sqlite3_result_error_code(sqlite3_context*, int); 5956void sqlite3_result_int(sqlite3_context*, int); 5957void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 5958void sqlite3_result_null(sqlite3_context*); 5959void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 5960void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 5961 void(*)(void*), unsigned char encoding); 5962void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 5963void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 5964void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 5965void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 5966void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 5967void sqlite3_result_zeroblob(sqlite3_context*, int n); 5968int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 5969 5970 5971/* 5972** CAPI3REF: Setting The Subtype Of An SQL Function 5973** METHOD: sqlite3_context 5974** 5975** The sqlite3_result_subtype(C,T) function causes the subtype of 5976** the result from the [application-defined SQL function] with 5977** [sqlite3_context] C to be the value T. Only the lower 8 bits 5978** of the subtype T are preserved in current versions of SQLite; 5979** higher order bits are discarded. 5980** The number of subtype bytes preserved by SQLite might increase 5981** in future releases of SQLite. 5982*/ 5983void sqlite3_result_subtype(sqlite3_context*,unsigned int); 5984 5985/* 5986** CAPI3REF: Define New Collating Sequences 5987** METHOD: sqlite3 5988** 5989** ^These functions add, remove, or modify a [collation] associated 5990** with the [database connection] specified as the first argument. 5991** 5992** ^The name of the collation is a UTF-8 string 5993** for sqlite3_create_collation() and sqlite3_create_collation_v2() 5994** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 5995** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 5996** considered to be the same name. 5997** 5998** ^(The third argument (eTextRep) must be one of the constants: 5999** <ul> 6000** <li> [SQLITE_UTF8], 6001** <li> [SQLITE_UTF16LE], 6002** <li> [SQLITE_UTF16BE], 6003** <li> [SQLITE_UTF16], or 6004** <li> [SQLITE_UTF16_ALIGNED]. 6005** </ul>)^ 6006** ^The eTextRep argument determines the encoding of strings passed 6007** to the collating function callback, xCompare. 6008** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 6009** force strings to be UTF16 with native byte order. 6010** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 6011** on an even byte address. 6012** 6013** ^The fourth argument, pArg, is an application data pointer that is passed 6014** through as the first argument to the collating function callback. 6015** 6016** ^The fifth argument, xCompare, is a pointer to the collating function. 6017** ^Multiple collating functions can be registered using the same name but 6018** with different eTextRep parameters and SQLite will use whichever 6019** function requires the least amount of data transformation. 6020** ^If the xCompare argument is NULL then the collating function is 6021** deleted. ^When all collating functions having the same name are deleted, 6022** that collation is no longer usable. 6023** 6024** ^The collating function callback is invoked with a copy of the pArg 6025** application data pointer and with two strings in the encoding specified 6026** by the eTextRep argument. The two integer parameters to the collating 6027** function callback are the length of the two strings, in bytes. The collating 6028** function must return an integer that is negative, zero, or positive 6029** if the first string is less than, equal to, or greater than the second, 6030** respectively. A collating function must always return the same answer 6031** given the same inputs. If two or more collating functions are registered 6032** to the same collation name (using different eTextRep values) then all 6033** must give an equivalent answer when invoked with equivalent strings. 6034** The collating function must obey the following properties for all 6035** strings A, B, and C: 6036** 6037** <ol> 6038** <li> If A==B then B==A. 6039** <li> If A==B and B==C then A==C. 6040** <li> If A<B THEN B>A. 6041** <li> If A<B and B<C then A<C. 6042** </ol> 6043** 6044** If a collating function fails any of the above constraints and that 6045** collating function is registered and used, then the behavior of SQLite 6046** is undefined. 6047** 6048** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 6049** with the addition that the xDestroy callback is invoked on pArg when 6050** the collating function is deleted. 6051** ^Collating functions are deleted when they are overridden by later 6052** calls to the collation creation functions or when the 6053** [database connection] is closed using [sqlite3_close()]. 6054** 6055** ^The xDestroy callback is <u>not</u> called if the 6056** sqlite3_create_collation_v2() function fails. Applications that invoke 6057** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 6058** check the return code and dispose of the application data pointer 6059** themselves rather than expecting SQLite to deal with it for them. 6060** This is different from every other SQLite interface. The inconsistency 6061** is unfortunate but cannot be changed without breaking backwards 6062** compatibility. 6063** 6064** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 6065*/ 6066int sqlite3_create_collation( 6067 sqlite3*, 6068 const char *zName, 6069 int eTextRep, 6070 void *pArg, 6071 int(*xCompare)(void*,int,const void*,int,const void*) 6072); 6073int sqlite3_create_collation_v2( 6074 sqlite3*, 6075 const char *zName, 6076 int eTextRep, 6077 void *pArg, 6078 int(*xCompare)(void*,int,const void*,int,const void*), 6079 void(*xDestroy)(void*) 6080); 6081int sqlite3_create_collation16( 6082 sqlite3*, 6083 const void *zName, 6084 int eTextRep, 6085 void *pArg, 6086 int(*xCompare)(void*,int,const void*,int,const void*) 6087); 6088 6089/* 6090** CAPI3REF: Collation Needed Callbacks 6091** METHOD: sqlite3 6092** 6093** ^To avoid having to register all collation sequences before a database 6094** can be used, a single callback function may be registered with the 6095** [database connection] to be invoked whenever an undefined collation 6096** sequence is required. 6097** 6098** ^If the function is registered using the sqlite3_collation_needed() API, 6099** then it is passed the names of undefined collation sequences as strings 6100** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 6101** the names are passed as UTF-16 in machine native byte order. 6102** ^A call to either function replaces the existing collation-needed callback. 6103** 6104** ^(When the callback is invoked, the first argument passed is a copy 6105** of the second argument to sqlite3_collation_needed() or 6106** sqlite3_collation_needed16(). The second argument is the database 6107** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 6108** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 6109** sequence function required. The fourth parameter is the name of the 6110** required collation sequence.)^ 6111** 6112** The callback function should register the desired collation using 6113** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 6114** [sqlite3_create_collation_v2()]. 6115*/ 6116int sqlite3_collation_needed( 6117 sqlite3*, 6118 void*, 6119 void(*)(void*,sqlite3*,int eTextRep,const char*) 6120); 6121int sqlite3_collation_needed16( 6122 sqlite3*, 6123 void*, 6124 void(*)(void*,sqlite3*,int eTextRep,const void*) 6125); 6126 6127#ifdef SQLITE_ENABLE_CEROD 6128/* 6129** Specify the activation key for a CEROD database. Unless 6130** activated, none of the CEROD routines will work. 6131*/ 6132void sqlite3_activate_cerod( 6133 const char *zPassPhrase /* Activation phrase */ 6134); 6135#endif 6136 6137/* 6138** CAPI3REF: Suspend Execution For A Short Time 6139** 6140** The sqlite3_sleep() function causes the current thread to suspend execution 6141** for at least a number of milliseconds specified in its parameter. 6142** 6143** If the operating system does not support sleep requests with 6144** millisecond time resolution, then the time will be rounded up to 6145** the nearest second. The number of milliseconds of sleep actually 6146** requested from the operating system is returned. 6147** 6148** ^SQLite implements this interface by calling the xSleep() 6149** method of the default [sqlite3_vfs] object. If the xSleep() method 6150** of the default VFS is not implemented correctly, or not implemented at 6151** all, then the behavior of sqlite3_sleep() may deviate from the description 6152** in the previous paragraphs. 6153*/ 6154int sqlite3_sleep(int); 6155 6156/* 6157** CAPI3REF: Name Of The Folder Holding Temporary Files 6158** 6159** ^(If this global variable is made to point to a string which is 6160** the name of a folder (a.k.a. directory), then all temporary files 6161** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6162** will be placed in that directory.)^ ^If this variable 6163** is a NULL pointer, then SQLite performs a search for an appropriate 6164** temporary file directory. 6165** 6166** Applications are strongly discouraged from using this global variable. 6167** It is required to set a temporary folder on Windows Runtime (WinRT). 6168** But for all other platforms, it is highly recommended that applications 6169** neither read nor write this variable. This global variable is a relic 6170** that exists for backwards compatibility of legacy applications and should 6171** be avoided in new projects. 6172** 6173** It is not safe to read or modify this variable in more than one 6174** thread at a time. It is not safe to read or modify this variable 6175** if a [database connection] is being used at the same time in a separate 6176** thread. 6177** It is intended that this variable be set once 6178** as part of process initialization and before any SQLite interface 6179** routines have been called and that this variable remain unchanged 6180** thereafter. 6181** 6182** ^The [temp_store_directory pragma] may modify this variable and cause 6183** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6184** the [temp_store_directory pragma] always assumes that any string 6185** that this variable points to is held in memory obtained from 6186** [sqlite3_malloc] and the pragma may attempt to free that memory 6187** using [sqlite3_free]. 6188** Hence, if this variable is modified directly, either it should be 6189** made NULL or made to point to memory obtained from [sqlite3_malloc] 6190** or else the use of the [temp_store_directory pragma] should be avoided. 6191** Except when requested by the [temp_store_directory pragma], SQLite 6192** does not free the memory that sqlite3_temp_directory points to. If 6193** the application wants that memory to be freed, it must do 6194** so itself, taking care to only do so after all [database connection] 6195** objects have been destroyed. 6196** 6197** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6198** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6199** features that require the use of temporary files may fail. Here is an 6200** example of how to do this using C++ with the Windows Runtime: 6201** 6202** <blockquote><pre> 6203** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6204** TemporaryFolder->Path->Data(); 6205** char zPathBuf[MAX_PATH + 1]; 6206** memset(zPathBuf, 0, sizeof(zPathBuf)); 6207** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6208** NULL, NULL); 6209** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6210** </pre></blockquote> 6211*/ 6212SQLITE_EXTERN char *sqlite3_temp_directory; 6213 6214/* 6215** CAPI3REF: Name Of The Folder Holding Database Files 6216** 6217** ^(If this global variable is made to point to a string which is 6218** the name of a folder (a.k.a. directory), then all database files 6219** specified with a relative pathname and created or accessed by 6220** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6221** to be relative to that directory.)^ ^If this variable is a NULL 6222** pointer, then SQLite assumes that all database files specified 6223** with a relative pathname are relative to the current directory 6224** for the process. Only the windows VFS makes use of this global 6225** variable; it is ignored by the unix VFS. 6226** 6227** Changing the value of this variable while a database connection is 6228** open can result in a corrupt database. 6229** 6230** It is not safe to read or modify this variable in more than one 6231** thread at a time. It is not safe to read or modify this variable 6232** if a [database connection] is being used at the same time in a separate 6233** thread. 6234** It is intended that this variable be set once 6235** as part of process initialization and before any SQLite interface 6236** routines have been called and that this variable remain unchanged 6237** thereafter. 6238** 6239** ^The [data_store_directory pragma] may modify this variable and cause 6240** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6241** the [data_store_directory pragma] always assumes that any string 6242** that this variable points to is held in memory obtained from 6243** [sqlite3_malloc] and the pragma may attempt to free that memory 6244** using [sqlite3_free]. 6245** Hence, if this variable is modified directly, either it should be 6246** made NULL or made to point to memory obtained from [sqlite3_malloc] 6247** or else the use of the [data_store_directory pragma] should be avoided. 6248*/ 6249SQLITE_EXTERN char *sqlite3_data_directory; 6250 6251/* 6252** CAPI3REF: Win32 Specific Interface 6253** 6254** These interfaces are available only on Windows. The 6255** [sqlite3_win32_set_directory] interface is used to set the value associated 6256** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6257** zValue, depending on the value of the type parameter. The zValue parameter 6258** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6259** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6260** prior to being used. The [sqlite3_win32_set_directory] interface returns 6261** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6262** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6263** [sqlite3_data_directory] variable is intended to act as a replacement for 6264** the current directory on the sub-platforms of Win32 where that concept is 6265** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6266** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6267** sqlite3_win32_set_directory interface except the string parameter must be 6268** UTF-8 or UTF-16, respectively. 6269*/ 6270int sqlite3_win32_set_directory( 6271 unsigned long type, /* Identifier for directory being set or reset */ 6272 void *zValue /* New value for directory being set or reset */ 6273); 6274int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6275int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6276 6277/* 6278** CAPI3REF: Win32 Directory Types 6279** 6280** These macros are only available on Windows. They define the allowed values 6281** for the type argument to the [sqlite3_win32_set_directory] interface. 6282*/ 6283#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6284#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6285 6286/* 6287** CAPI3REF: Test For Auto-Commit Mode 6288** KEYWORDS: {autocommit mode} 6289** METHOD: sqlite3 6290** 6291** ^The sqlite3_get_autocommit() interface returns non-zero or 6292** zero if the given database connection is or is not in autocommit mode, 6293** respectively. ^Autocommit mode is on by default. 6294** ^Autocommit mode is disabled by a [BEGIN] statement. 6295** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6296** 6297** If certain kinds of errors occur on a statement within a multi-statement 6298** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6299** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6300** transaction might be rolled back automatically. The only way to 6301** find out whether SQLite automatically rolled back the transaction after 6302** an error is to use this function. 6303** 6304** If another thread changes the autocommit status of the database 6305** connection while this routine is running, then the return value 6306** is undefined. 6307*/ 6308int sqlite3_get_autocommit(sqlite3*); 6309 6310/* 6311** CAPI3REF: Find The Database Handle Of A Prepared Statement 6312** METHOD: sqlite3_stmt 6313** 6314** ^The sqlite3_db_handle interface returns the [database connection] handle 6315** to which a [prepared statement] belongs. ^The [database connection] 6316** returned by sqlite3_db_handle is the same [database connection] 6317** that was the first argument 6318** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6319** create the statement in the first place. 6320*/ 6321sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6322 6323/* 6324** CAPI3REF: Return The Schema Name For A Database Connection 6325** METHOD: sqlite3 6326** 6327** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name 6328** for the N-th database on database connection D, or a NULL pointer of N is 6329** out of range. An N value of 0 means the main database file. An N of 1 is 6330** the "temp" schema. Larger values of N correspond to various ATTACH-ed 6331** databases. 6332** 6333** Space to hold the string that is returned by sqlite3_db_name() is managed 6334** by SQLite itself. The string might be deallocated by any operation that 6335** changes the schema, including [ATTACH] or [DETACH] or calls to 6336** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that 6337** occur on a different thread. Applications that need to 6338** remember the string long-term should make their own copy. Applications that 6339** are accessing the same database connection simultaneously on multiple 6340** threads should mutex-protect calls to this API and should make their own 6341** private copy of the result prior to releasing the mutex. 6342*/ 6343const char *sqlite3_db_name(sqlite3 *db, int N); 6344 6345/* 6346** CAPI3REF: Return The Filename For A Database Connection 6347** METHOD: sqlite3 6348** 6349** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6350** associated with database N of connection D. 6351** ^If there is no attached database N on the database 6352** connection D, or if database N is a temporary or in-memory database, then 6353** this function will return either a NULL pointer or an empty string. 6354** 6355** ^The string value returned by this routine is owned and managed by 6356** the database connection. ^The value will be valid until the database N 6357** is [DETACH]-ed or until the database connection closes. 6358** 6359** ^The filename returned by this function is the output of the 6360** xFullPathname method of the [VFS]. ^In other words, the filename 6361** will be an absolute pathname, even if the filename used 6362** to open the database originally was a URI or relative pathname. 6363** 6364** If the filename pointer returned by this routine is not NULL, then it 6365** can be used as the filename input parameter to these routines: 6366** <ul> 6367** <li> [sqlite3_uri_parameter()] 6368** <li> [sqlite3_uri_boolean()] 6369** <li> [sqlite3_uri_int64()] 6370** <li> [sqlite3_filename_database()] 6371** <li> [sqlite3_filename_journal()] 6372** <li> [sqlite3_filename_wal()] 6373** </ul> 6374*/ 6375sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6376 6377/* 6378** CAPI3REF: Determine if a database is read-only 6379** METHOD: sqlite3 6380** 6381** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6382** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6383** the name of a database on connection D. 6384*/ 6385int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6386 6387/* 6388** CAPI3REF: Determine the transaction state of a database 6389** METHOD: sqlite3 6390** 6391** ^The sqlite3_txn_state(D,S) interface returns the current 6392** [transaction state] of schema S in database connection D. ^If S is NULL, 6393** then the highest transaction state of any schema on database connection D 6394** is returned. Transaction states are (in order of lowest to highest): 6395** <ol> 6396** <li value="0"> SQLITE_TXN_NONE 6397** <li value="1"> SQLITE_TXN_READ 6398** <li value="2"> SQLITE_TXN_WRITE 6399** </ol> 6400** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 6401** a valid schema, then -1 is returned. 6402*/ 6403int sqlite3_txn_state(sqlite3*,const char *zSchema); 6404 6405/* 6406** CAPI3REF: Allowed return values from [sqlite3_txn_state()] 6407** KEYWORDS: {transaction state} 6408** 6409** These constants define the current transaction state of a database file. 6410** ^The [sqlite3_txn_state(D,S)] interface returns one of these 6411** constants in order to describe the transaction state of schema S 6412** in [database connection] D. 6413** 6414** <dl> 6415** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 6416** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 6417** pending.</dd> 6418** 6419** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 6420** <dd>The SQLITE_TXN_READ state means that the database is currently 6421** in a read transaction. Content has been read from the database file 6422** but nothing in the database file has changed. The transaction state 6423** will advanced to SQLITE_TXN_WRITE if any changes occur and there are 6424** no other conflicting concurrent write transactions. The transaction 6425** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 6426** [COMMIT].</dd> 6427** 6428** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 6429** <dd>The SQLITE_TXN_WRITE state means that the database is currently 6430** in a write transaction. Content has been written to the database file 6431** but has not yet committed. The transaction state will change to 6432** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 6433*/ 6434#define SQLITE_TXN_NONE 0 6435#define SQLITE_TXN_READ 1 6436#define SQLITE_TXN_WRITE 2 6437 6438/* 6439** CAPI3REF: Find the next prepared statement 6440** METHOD: sqlite3 6441** 6442** ^This interface returns a pointer to the next [prepared statement] after 6443** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6444** then this interface returns a pointer to the first prepared statement 6445** associated with the database connection pDb. ^If no prepared statement 6446** satisfies the conditions of this routine, it returns NULL. 6447** 6448** The [database connection] pointer D in a call to 6449** [sqlite3_next_stmt(D,S)] must refer to an open database 6450** connection and in particular must not be a NULL pointer. 6451*/ 6452sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6453 6454/* 6455** CAPI3REF: Commit And Rollback Notification Callbacks 6456** METHOD: sqlite3 6457** 6458** ^The sqlite3_commit_hook() interface registers a callback 6459** function to be invoked whenever a transaction is [COMMIT | committed]. 6460** ^Any callback set by a previous call to sqlite3_commit_hook() 6461** for the same database connection is overridden. 6462** ^The sqlite3_rollback_hook() interface registers a callback 6463** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6464** ^Any callback set by a previous call to sqlite3_rollback_hook() 6465** for the same database connection is overridden. 6466** ^The pArg argument is passed through to the callback. 6467** ^If the callback on a commit hook function returns non-zero, 6468** then the commit is converted into a rollback. 6469** 6470** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6471** return the P argument from the previous call of the same function 6472** on the same [database connection] D, or NULL for 6473** the first call for each function on D. 6474** 6475** The commit and rollback hook callbacks are not reentrant. 6476** The callback implementation must not do anything that will modify 6477** the database connection that invoked the callback. Any actions 6478** to modify the database connection must be deferred until after the 6479** completion of the [sqlite3_step()] call that triggered the commit 6480** or rollback hook in the first place. 6481** Note that running any other SQL statements, including SELECT statements, 6482** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6483** the database connections for the meaning of "modify" in this paragraph. 6484** 6485** ^Registering a NULL function disables the callback. 6486** 6487** ^When the commit hook callback routine returns zero, the [COMMIT] 6488** operation is allowed to continue normally. ^If the commit hook 6489** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6490** ^The rollback hook is invoked on a rollback that results from a commit 6491** hook returning non-zero, just as it would be with any other rollback. 6492** 6493** ^For the purposes of this API, a transaction is said to have been 6494** rolled back if an explicit "ROLLBACK" statement is executed, or 6495** an error or constraint causes an implicit rollback to occur. 6496** ^The rollback callback is not invoked if a transaction is 6497** automatically rolled back because the database connection is closed. 6498** 6499** See also the [sqlite3_update_hook()] interface. 6500*/ 6501void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6502void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6503 6504/* 6505** CAPI3REF: Autovacuum Compaction Amount Callback 6506** METHOD: sqlite3 6507** 6508** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback 6509** function C that is invoked prior to each autovacuum of the database 6510** file. ^The callback is passed a copy of the generic data pointer (P), 6511** the schema-name of the attached database that is being autovacuumed, 6512** the size of the database file in pages, the number of free pages, 6513** and the number of bytes per page, respectively. The callback should 6514** return the number of free pages that should be removed by the 6515** autovacuum. ^If the callback returns zero, then no autovacuum happens. 6516** ^If the value returned is greater than or equal to the number of 6517** free pages, then a complete autovacuum happens. 6518** 6519** <p>^If there are multiple ATTACH-ed database files that are being 6520** modified as part of a transaction commit, then the autovacuum pages 6521** callback is invoked separately for each file. 6522** 6523** <p><b>The callback is not reentrant.</b> The callback function should 6524** not attempt to invoke any other SQLite interface. If it does, bad 6525** things may happen, including segmentation faults and corrupt database 6526** files. The callback function should be a simple function that 6527** does some arithmetic on its input parameters and returns a result. 6528** 6529** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional 6530** destructor for the P parameter. ^If X is not NULL, then X(P) is 6531** invoked whenever the database connection closes or when the callback 6532** is overwritten by another invocation of sqlite3_autovacuum_pages(). 6533** 6534** <p>^There is only one autovacuum pages callback per database connection. 6535** ^Each call to the sqlite3_autovacuum_pages() interface overrides all 6536** previous invocations for that database connection. ^If the callback 6537** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, 6538** then the autovacuum steps callback is cancelled. The return value 6539** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might 6540** be some other error code if something goes wrong. The current 6541** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other 6542** return codes might be added in future releases. 6543** 6544** <p>If no autovacuum pages callback is specified (the usual case) or 6545** a NULL pointer is provided for the callback, 6546** then the default behavior is to vacuum all free pages. So, in other 6547** words, the default behavior is the same as if the callback function 6548** were something like this: 6549** 6550** <blockquote><pre> 6551** unsigned int demonstration_autovac_pages_callback( 6552** void *pClientData, 6553** const char *zSchema, 6554** unsigned int nDbPage, 6555** unsigned int nFreePage, 6556** unsigned int nBytePerPage 6557** ){ 6558** return nFreePage; 6559** } 6560** </pre></blockquote> 6561*/ 6562int sqlite3_autovacuum_pages( 6563 sqlite3 *db, 6564 unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), 6565 void*, 6566 void(*)(void*) 6567); 6568 6569 6570/* 6571** CAPI3REF: Data Change Notification Callbacks 6572** METHOD: sqlite3 6573** 6574** ^The sqlite3_update_hook() interface registers a callback function 6575** with the [database connection] identified by the first argument 6576** to be invoked whenever a row is updated, inserted or deleted in 6577** a [rowid table]. 6578** ^Any callback set by a previous call to this function 6579** for the same database connection is overridden. 6580** 6581** ^The second argument is a pointer to the function to invoke when a 6582** row is updated, inserted or deleted in a rowid table. 6583** ^The first argument to the callback is a copy of the third argument 6584** to sqlite3_update_hook(). 6585** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6586** or [SQLITE_UPDATE], depending on the operation that caused the callback 6587** to be invoked. 6588** ^The third and fourth arguments to the callback contain pointers to the 6589** database and table name containing the affected row. 6590** ^The final callback parameter is the [rowid] of the row. 6591** ^In the case of an update, this is the [rowid] after the update takes place. 6592** 6593** ^(The update hook is not invoked when internal system tables are 6594** modified (i.e. sqlite_sequence).)^ 6595** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6596** 6597** ^In the current implementation, the update hook 6598** is not invoked when conflicting rows are deleted because of an 6599** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6600** invoked when rows are deleted using the [truncate optimization]. 6601** The exceptions defined in this paragraph might change in a future 6602** release of SQLite. 6603** 6604** The update hook implementation must not do anything that will modify 6605** the database connection that invoked the update hook. Any actions 6606** to modify the database connection must be deferred until after the 6607** completion of the [sqlite3_step()] call that triggered the update hook. 6608** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6609** database connections for the meaning of "modify" in this paragraph. 6610** 6611** ^The sqlite3_update_hook(D,C,P) function 6612** returns the P argument from the previous call 6613** on the same [database connection] D, or NULL for 6614** the first call on D. 6615** 6616** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6617** and [sqlite3_preupdate_hook()] interfaces. 6618*/ 6619void *sqlite3_update_hook( 6620 sqlite3*, 6621 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6622 void* 6623); 6624 6625/* 6626** CAPI3REF: Enable Or Disable Shared Pager Cache 6627** 6628** ^(This routine enables or disables the sharing of the database cache 6629** and schema data structures between [database connection | connections] 6630** to the same database. Sharing is enabled if the argument is true 6631** and disabled if the argument is false.)^ 6632** 6633** This interface is omitted if SQLite is compiled with 6634** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] 6635** compile-time option is recommended because the 6636** [use of shared cache mode is discouraged]. 6637** 6638** ^Cache sharing is enabled and disabled for an entire process. 6639** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6640** In prior versions of SQLite, 6641** sharing was enabled or disabled for each thread separately. 6642** 6643** ^(The cache sharing mode set by this interface effects all subsequent 6644** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6645** Existing database connections continue to use the sharing mode 6646** that was in effect at the time they were opened.)^ 6647** 6648** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6649** successfully. An [error code] is returned otherwise.)^ 6650** 6651** ^Shared cache is disabled by default. It is recommended that it stay 6652** that way. In other words, do not use this routine. This interface 6653** continues to be provided for historical compatibility, but its use is 6654** discouraged. Any use of shared cache is discouraged. If shared cache 6655** must be used, it is recommended that shared cache only be enabled for 6656** individual database connections using the [sqlite3_open_v2()] interface 6657** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6658** 6659** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6660** and will always return SQLITE_MISUSE. On those systems, 6661** shared cache mode should be enabled per-database connection via 6662** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6663** 6664** This interface is threadsafe on processors where writing a 6665** 32-bit integer is atomic. 6666** 6667** See Also: [SQLite Shared-Cache Mode] 6668*/ 6669int sqlite3_enable_shared_cache(int); 6670 6671/* 6672** CAPI3REF: Attempt To Free Heap Memory 6673** 6674** ^The sqlite3_release_memory() interface attempts to free N bytes 6675** of heap memory by deallocating non-essential memory allocations 6676** held by the database library. Memory used to cache database 6677** pages to improve performance is an example of non-essential memory. 6678** ^sqlite3_release_memory() returns the number of bytes actually freed, 6679** which might be more or less than the amount requested. 6680** ^The sqlite3_release_memory() routine is a no-op returning zero 6681** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6682** 6683** See also: [sqlite3_db_release_memory()] 6684*/ 6685int sqlite3_release_memory(int); 6686 6687/* 6688** CAPI3REF: Free Memory Used By A Database Connection 6689** METHOD: sqlite3 6690** 6691** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6692** memory as possible from database connection D. Unlike the 6693** [sqlite3_release_memory()] interface, this interface is in effect even 6694** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6695** omitted. 6696** 6697** See also: [sqlite3_release_memory()] 6698*/ 6699int sqlite3_db_release_memory(sqlite3*); 6700 6701/* 6702** CAPI3REF: Impose A Limit On Heap Size 6703** 6704** These interfaces impose limits on the amount of heap memory that will be 6705** by all database connections within a single process. 6706** 6707** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 6708** soft limit on the amount of heap memory that may be allocated by SQLite. 6709** ^SQLite strives to keep heap memory utilization below the soft heap 6710** limit by reducing the number of pages held in the page cache 6711** as heap memory usages approaches the limit. 6712** ^The soft heap limit is "soft" because even though SQLite strives to stay 6713** below the limit, it will exceed the limit rather than generate 6714** an [SQLITE_NOMEM] error. In other words, the soft heap limit 6715** is advisory only. 6716** 6717** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 6718** N bytes on the amount of memory that will be allocated. ^The 6719** sqlite3_hard_heap_limit64(N) interface is similar to 6720** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 6721** when the hard heap limit is reached. 6722** 6723** ^The return value from both sqlite3_soft_heap_limit64() and 6724** sqlite3_hard_heap_limit64() is the size of 6725** the heap limit prior to the call, or negative in the case of an 6726** error. ^If the argument N is negative 6727** then no change is made to the heap limit. Hence, the current 6728** size of heap limits can be determined by invoking 6729** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 6730** 6731** ^Setting the heap limits to zero disables the heap limiter mechanism. 6732** 6733** ^The soft heap limit may not be greater than the hard heap limit. 6734** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 6735** is invoked with a value of N that is greater than the hard heap limit, 6736** the soft heap limit is set to the value of the hard heap limit. 6737** ^The soft heap limit is automatically enabled whenever the hard heap 6738** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 6739** the soft heap limit is outside the range of 1..N, then the soft heap 6740** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 6741** hard heap limit is enabled makes the soft heap limit equal to the 6742** hard heap limit. 6743** 6744** The memory allocation limits can also be adjusted using 6745** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 6746** 6747** ^(The heap limits are not enforced in the current implementation 6748** if one or more of following conditions are true: 6749** 6750** <ul> 6751** <li> The limit value is set to zero. 6752** <li> Memory accounting is disabled using a combination of the 6753** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 6754** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 6755** <li> An alternative page cache implementation is specified using 6756** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 6757** <li> The page cache allocates from its own memory pool supplied 6758** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 6759** from the heap. 6760** </ul>)^ 6761** 6762** The circumstances under which SQLite will enforce the heap limits may 6763** changes in future releases of SQLite. 6764*/ 6765sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 6766sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 6767 6768/* 6769** CAPI3REF: Deprecated Soft Heap Limit Interface 6770** DEPRECATED 6771** 6772** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 6773** interface. This routine is provided for historical compatibility 6774** only. All new applications should use the 6775** [sqlite3_soft_heap_limit64()] interface rather than this one. 6776*/ 6777SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 6778 6779 6780/* 6781** CAPI3REF: Extract Metadata About A Column Of A Table 6782** METHOD: sqlite3 6783** 6784** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 6785** information about column C of table T in database D 6786** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 6787** interface returns SQLITE_OK and fills in the non-NULL pointers in 6788** the final five arguments with appropriate values if the specified 6789** column exists. ^The sqlite3_table_column_metadata() interface returns 6790** SQLITE_ERROR if the specified column does not exist. 6791** ^If the column-name parameter to sqlite3_table_column_metadata() is a 6792** NULL pointer, then this routine simply checks for the existence of the 6793** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 6794** does not. If the table name parameter T in a call to 6795** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 6796** undefined behavior. 6797** 6798** ^The column is identified by the second, third and fourth parameters to 6799** this function. ^(The second parameter is either the name of the database 6800** (i.e. "main", "temp", or an attached database) containing the specified 6801** table or NULL.)^ ^If it is NULL, then all attached databases are searched 6802** for the table using the same algorithm used by the database engine to 6803** resolve unqualified table references. 6804** 6805** ^The third and fourth parameters to this function are the table and column 6806** name of the desired column, respectively. 6807** 6808** ^Metadata is returned by writing to the memory locations passed as the 5th 6809** and subsequent parameters to this function. ^Any of these arguments may be 6810** NULL, in which case the corresponding element of metadata is omitted. 6811** 6812** ^(<blockquote> 6813** <table border="1"> 6814** <tr><th> Parameter <th> Output<br>Type <th> Description 6815** 6816** <tr><td> 5th <td> const char* <td> Data type 6817** <tr><td> 6th <td> const char* <td> Name of default collation sequence 6818** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 6819** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 6820** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 6821** </table> 6822** </blockquote>)^ 6823** 6824** ^The memory pointed to by the character pointers returned for the 6825** declaration type and collation sequence is valid until the next 6826** call to any SQLite API function. 6827** 6828** ^If the specified table is actually a view, an [error code] is returned. 6829** 6830** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 6831** is not a [WITHOUT ROWID] table and an 6832** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 6833** parameters are set for the explicitly declared column. ^(If there is no 6834** [INTEGER PRIMARY KEY] column, then the outputs 6835** for the [rowid] are set as follows: 6836** 6837** <pre> 6838** data type: "INTEGER" 6839** collation sequence: "BINARY" 6840** not null: 0 6841** primary key: 1 6842** auto increment: 0 6843** </pre>)^ 6844** 6845** ^This function causes all database schemas to be read from disk and 6846** parsed, if that has not already been done, and returns an error if 6847** any errors are encountered while loading the schema. 6848*/ 6849int sqlite3_table_column_metadata( 6850 sqlite3 *db, /* Connection handle */ 6851 const char *zDbName, /* Database name or NULL */ 6852 const char *zTableName, /* Table name */ 6853 const char *zColumnName, /* Column name */ 6854 char const **pzDataType, /* OUTPUT: Declared data type */ 6855 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 6856 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 6857 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 6858 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 6859); 6860 6861/* 6862** CAPI3REF: Load An Extension 6863** METHOD: sqlite3 6864** 6865** ^This interface loads an SQLite extension library from the named file. 6866** 6867** ^The sqlite3_load_extension() interface attempts to load an 6868** [SQLite extension] library contained in the file zFile. If 6869** the file cannot be loaded directly, attempts are made to load 6870** with various operating-system specific extensions added. 6871** So for example, if "samplelib" cannot be loaded, then names like 6872** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 6873** be tried also. 6874** 6875** ^The entry point is zProc. 6876** ^(zProc may be 0, in which case SQLite will try to come up with an 6877** entry point name on its own. It first tries "sqlite3_extension_init". 6878** If that does not work, it constructs a name "sqlite3_X_init" where the 6879** X is consists of the lower-case equivalent of all ASCII alphabetic 6880** characters in the filename from the last "/" to the first following 6881** "." and omitting any initial "lib".)^ 6882** ^The sqlite3_load_extension() interface returns 6883** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 6884** ^If an error occurs and pzErrMsg is not 0, then the 6885** [sqlite3_load_extension()] interface shall attempt to 6886** fill *pzErrMsg with error message text stored in memory 6887** obtained from [sqlite3_malloc()]. The calling function 6888** should free this memory by calling [sqlite3_free()]. 6889** 6890** ^Extension loading must be enabled using 6891** [sqlite3_enable_load_extension()] or 6892** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 6893** prior to calling this API, 6894** otherwise an error will be returned. 6895** 6896** <b>Security warning:</b> It is recommended that the 6897** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 6898** interface. The use of the [sqlite3_enable_load_extension()] interface 6899** should be avoided. This will keep the SQL function [load_extension()] 6900** disabled and prevent SQL injections from giving attackers 6901** access to extension loading capabilities. 6902** 6903** See also the [load_extension() SQL function]. 6904*/ 6905int sqlite3_load_extension( 6906 sqlite3 *db, /* Load the extension into this database connection */ 6907 const char *zFile, /* Name of the shared library containing extension */ 6908 const char *zProc, /* Entry point. Derived from zFile if 0 */ 6909 char **pzErrMsg /* Put error message here if not 0 */ 6910); 6911 6912/* 6913** CAPI3REF: Enable Or Disable Extension Loading 6914** METHOD: sqlite3 6915** 6916** ^So as not to open security holes in older applications that are 6917** unprepared to deal with [extension loading], and as a means of disabling 6918** [extension loading] while evaluating user-entered SQL, the following API 6919** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 6920** 6921** ^Extension loading is off by default. 6922** ^Call the sqlite3_enable_load_extension() routine with onoff==1 6923** to turn extension loading on and call it with onoff==0 to turn 6924** it back off again. 6925** 6926** ^This interface enables or disables both the C-API 6927** [sqlite3_load_extension()] and the SQL function [load_extension()]. 6928** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 6929** to enable or disable only the C-API.)^ 6930** 6931** <b>Security warning:</b> It is recommended that extension loading 6932** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 6933** rather than this interface, so the [load_extension()] SQL function 6934** remains disabled. This will prevent SQL injections from giving attackers 6935** access to extension loading capabilities. 6936*/ 6937int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 6938 6939/* 6940** CAPI3REF: Automatically Load Statically Linked Extensions 6941** 6942** ^This interface causes the xEntryPoint() function to be invoked for 6943** each new [database connection] that is created. The idea here is that 6944** xEntryPoint() is the entry point for a statically linked [SQLite extension] 6945** that is to be automatically loaded into all new database connections. 6946** 6947** ^(Even though the function prototype shows that xEntryPoint() takes 6948** no arguments and returns void, SQLite invokes xEntryPoint() with three 6949** arguments and expects an integer result as if the signature of the 6950** entry point where as follows: 6951** 6952** <blockquote><pre> 6953** int xEntryPoint( 6954** sqlite3 *db, 6955** const char **pzErrMsg, 6956** const struct sqlite3_api_routines *pThunk 6957** ); 6958** </pre></blockquote>)^ 6959** 6960** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 6961** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 6962** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 6963** is NULL before calling the xEntryPoint(). ^SQLite will invoke 6964** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 6965** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 6966** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 6967** 6968** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 6969** on the list of automatic extensions is a harmless no-op. ^No entry point 6970** will be called more than once for each database connection that is opened. 6971** 6972** See also: [sqlite3_reset_auto_extension()] 6973** and [sqlite3_cancel_auto_extension()] 6974*/ 6975int sqlite3_auto_extension(void(*xEntryPoint)(void)); 6976 6977/* 6978** CAPI3REF: Cancel Automatic Extension Loading 6979** 6980** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 6981** initialization routine X that was registered using a prior call to 6982** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 6983** routine returns 1 if initialization routine X was successfully 6984** unregistered and it returns 0 if X was not on the list of initialization 6985** routines. 6986*/ 6987int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 6988 6989/* 6990** CAPI3REF: Reset Automatic Extension Loading 6991** 6992** ^This interface disables all automatic extensions previously 6993** registered using [sqlite3_auto_extension()]. 6994*/ 6995void sqlite3_reset_auto_extension(void); 6996 6997/* 6998** The interface to the virtual-table mechanism is currently considered 6999** to be experimental. The interface might change in incompatible ways. 7000** If this is a problem for you, do not use the interface at this time. 7001** 7002** When the virtual-table mechanism stabilizes, we will declare the 7003** interface fixed, support it indefinitely, and remove this comment. 7004*/ 7005 7006/* 7007** Structures used by the virtual table interface 7008*/ 7009typedef struct sqlite3_vtab sqlite3_vtab; 7010typedef struct sqlite3_index_info sqlite3_index_info; 7011typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 7012typedef struct sqlite3_module sqlite3_module; 7013 7014/* 7015** CAPI3REF: Virtual Table Object 7016** KEYWORDS: sqlite3_module {virtual table module} 7017** 7018** This structure, sometimes called a "virtual table module", 7019** defines the implementation of a [virtual table]. 7020** This structure consists mostly of methods for the module. 7021** 7022** ^A virtual table module is created by filling in a persistent 7023** instance of this structure and passing a pointer to that instance 7024** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 7025** ^The registration remains valid until it is replaced by a different 7026** module or until the [database connection] closes. The content 7027** of this structure must not change while it is registered with 7028** any database connection. 7029*/ 7030struct sqlite3_module { 7031 int iVersion; 7032 int (*xCreate)(sqlite3*, void *pAux, 7033 int argc, const char *const*argv, 7034 sqlite3_vtab **ppVTab, char**); 7035 int (*xConnect)(sqlite3*, void *pAux, 7036 int argc, const char *const*argv, 7037 sqlite3_vtab **ppVTab, char**); 7038 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 7039 int (*xDisconnect)(sqlite3_vtab *pVTab); 7040 int (*xDestroy)(sqlite3_vtab *pVTab); 7041 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 7042 int (*xClose)(sqlite3_vtab_cursor*); 7043 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 7044 int argc, sqlite3_value **argv); 7045 int (*xNext)(sqlite3_vtab_cursor*); 7046 int (*xEof)(sqlite3_vtab_cursor*); 7047 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 7048 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 7049 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 7050 int (*xBegin)(sqlite3_vtab *pVTab); 7051 int (*xSync)(sqlite3_vtab *pVTab); 7052 int (*xCommit)(sqlite3_vtab *pVTab); 7053 int (*xRollback)(sqlite3_vtab *pVTab); 7054 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 7055 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 7056 void **ppArg); 7057 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 7058 /* The methods above are in version 1 of the sqlite_module object. Those 7059 ** below are for version 2 and greater. */ 7060 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 7061 int (*xRelease)(sqlite3_vtab *pVTab, int); 7062 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 7063 /* The methods above are in versions 1 and 2 of the sqlite_module object. 7064 ** Those below are for version 3 and greater. */ 7065 int (*xShadowName)(const char*); 7066}; 7067 7068/* 7069** CAPI3REF: Virtual Table Indexing Information 7070** KEYWORDS: sqlite3_index_info 7071** 7072** The sqlite3_index_info structure and its substructures is used as part 7073** of the [virtual table] interface to 7074** pass information into and receive the reply from the [xBestIndex] 7075** method of a [virtual table module]. The fields under **Inputs** are the 7076** inputs to xBestIndex and are read-only. xBestIndex inserts its 7077** results into the **Outputs** fields. 7078** 7079** ^(The aConstraint[] array records WHERE clause constraints of the form: 7080** 7081** <blockquote>column OP expr</blockquote> 7082** 7083** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 7084** stored in aConstraint[].op using one of the 7085** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 7086** ^(The index of the column is stored in 7087** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 7088** expr on the right-hand side can be evaluated (and thus the constraint 7089** is usable) and false if it cannot.)^ 7090** 7091** ^The optimizer automatically inverts terms of the form "expr OP column" 7092** and makes other simplifications to the WHERE clause in an attempt to 7093** get as many WHERE clause terms into the form shown above as possible. 7094** ^The aConstraint[] array only reports WHERE clause terms that are 7095** relevant to the particular virtual table being queried. 7096** 7097** ^Information about the ORDER BY clause is stored in aOrderBy[]. 7098** ^Each term of aOrderBy records a column of the ORDER BY clause. 7099** 7100** The colUsed field indicates which columns of the virtual table may be 7101** required by the current scan. Virtual table columns are numbered from 7102** zero in the order in which they appear within the CREATE TABLE statement 7103** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 7104** the corresponding bit is set within the colUsed mask if the column may be 7105** required by SQLite. If the table has at least 64 columns and any column 7106** to the right of the first 63 is required, then bit 63 of colUsed is also 7107** set. In other words, column iCol may be required if the expression 7108** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 7109** non-zero. 7110** 7111** The [xBestIndex] method must fill aConstraintUsage[] with information 7112** about what parameters to pass to xFilter. ^If argvIndex>0 then 7113** the right-hand side of the corresponding aConstraint[] is evaluated 7114** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 7115** is true, then the constraint is assumed to be fully handled by the 7116** virtual table and might not be checked again by the byte code.)^ ^(The 7117** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 7118** is left in its default setting of false, the constraint will always be 7119** checked separately in byte code. If the omit flag is change to true, then 7120** the constraint may or may not be checked in byte code. In other words, 7121** when the omit flag is true there is no guarantee that the constraint will 7122** not be checked again using byte code.)^ 7123** 7124** ^The idxNum and idxPtr values are recorded and passed into the 7125** [xFilter] method. 7126** ^[sqlite3_free()] is used to free idxPtr if and only if 7127** needToFreeIdxPtr is true. 7128** 7129** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 7130** the correct order to satisfy the ORDER BY clause so that no separate 7131** sorting step is required. 7132** 7133** ^The estimatedCost value is an estimate of the cost of a particular 7134** strategy. A cost of N indicates that the cost of the strategy is similar 7135** to a linear scan of an SQLite table with N rows. A cost of log(N) 7136** indicates that the expense of the operation is similar to that of a 7137** binary search on a unique indexed field of an SQLite table with N rows. 7138** 7139** ^The estimatedRows value is an estimate of the number of rows that 7140** will be returned by the strategy. 7141** 7142** The xBestIndex method may optionally populate the idxFlags field with a 7143** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 7144** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 7145** assumes that the strategy may visit at most one row. 7146** 7147** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 7148** SQLite also assumes that if a call to the xUpdate() method is made as 7149** part of the same statement to delete or update a virtual table row and the 7150** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 7151** any database changes. In other words, if the xUpdate() returns 7152** SQLITE_CONSTRAINT, the database contents must be exactly as they were 7153** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 7154** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 7155** the xUpdate method are automatically rolled back by SQLite. 7156** 7157** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 7158** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 7159** If a virtual table extension is 7160** used with an SQLite version earlier than 3.8.2, the results of attempting 7161** to read or write the estimatedRows field are undefined (but are likely 7162** to include crashing the application). The estimatedRows field should 7163** therefore only be used if [sqlite3_libversion_number()] returns a 7164** value greater than or equal to 3008002. Similarly, the idxFlags field 7165** was added for [version 3.9.0] ([dateof:3.9.0]). 7166** It may therefore only be used if 7167** sqlite3_libversion_number() returns a value greater than or equal to 7168** 3009000. 7169*/ 7170struct sqlite3_index_info { 7171 /* Inputs */ 7172 int nConstraint; /* Number of entries in aConstraint */ 7173 struct sqlite3_index_constraint { 7174 int iColumn; /* Column constrained. -1 for ROWID */ 7175 unsigned char op; /* Constraint operator */ 7176 unsigned char usable; /* True if this constraint is usable */ 7177 int iTermOffset; /* Used internally - xBestIndex should ignore */ 7178 } *aConstraint; /* Table of WHERE clause constraints */ 7179 int nOrderBy; /* Number of terms in the ORDER BY clause */ 7180 struct sqlite3_index_orderby { 7181 int iColumn; /* Column number */ 7182 unsigned char desc; /* True for DESC. False for ASC. */ 7183 } *aOrderBy; /* The ORDER BY clause */ 7184 /* Outputs */ 7185 struct sqlite3_index_constraint_usage { 7186 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 7187 unsigned char omit; /* Do not code a test for this constraint */ 7188 } *aConstraintUsage; 7189 int idxNum; /* Number used to identify the index */ 7190 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 7191 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 7192 int orderByConsumed; /* True if output is already ordered */ 7193 double estimatedCost; /* Estimated cost of using this index */ 7194 /* Fields below are only available in SQLite 3.8.2 and later */ 7195 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 7196 /* Fields below are only available in SQLite 3.9.0 and later */ 7197 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 7198 /* Fields below are only available in SQLite 3.10.0 and later */ 7199 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 7200}; 7201 7202/* 7203** CAPI3REF: Virtual Table Scan Flags 7204** 7205** Virtual table implementations are allowed to set the 7206** [sqlite3_index_info].idxFlags field to some combination of 7207** these bits. 7208*/ 7209#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 7210 7211/* 7212** CAPI3REF: Virtual Table Constraint Operator Codes 7213** 7214** These macros define the allowed values for the 7215** [sqlite3_index_info].aConstraint[].op field. Each value represents 7216** an operator that is part of a constraint term in the WHERE clause of 7217** a query that uses a [virtual table]. 7218** 7219** ^The left-hand operand of the operator is given by the corresponding 7220** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand 7221** operand is the rowid. 7222** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET 7223** operators have no left-hand operand, and so for those operators the 7224** corresponding aConstraint[].iColumn is meaningless and should not be 7225** used. 7226** 7227** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through 7228** value 255 are reserved to represent functions that are overloaded 7229** by the [xFindFunction|xFindFunction method] of the virtual table 7230** implementation. 7231** 7232** The right-hand operands for each constraint might be accessible using 7233** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand 7234** operand is only available if it appears as a single constant literal 7235** in the input SQL. If the right-hand operand is another column or an 7236** expression (even a constant expression) or a parameter, then the 7237** sqlite3_vtab_rhs_value() probably will not be able to extract it. 7238** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and 7239** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand 7240** and hence calls to sqlite3_vtab_rhs_value() for those operators will 7241** always return SQLITE_NOTFOUND. 7242** 7243** The collating sequence to be used for comparison can be found using 7244** the [sqlite3_vtab_collation()] interface. For most real-world virtual 7245** tables, the collating sequence of constraints does not matter (for example 7246** because the constraints are numeric) and so the sqlite3_vtab_collation() 7247** interface is no commonly needed. 7248*/ 7249#define SQLITE_INDEX_CONSTRAINT_EQ 2 7250#define SQLITE_INDEX_CONSTRAINT_GT 4 7251#define SQLITE_INDEX_CONSTRAINT_LE 8 7252#define SQLITE_INDEX_CONSTRAINT_LT 16 7253#define SQLITE_INDEX_CONSTRAINT_GE 32 7254#define SQLITE_INDEX_CONSTRAINT_MATCH 64 7255#define SQLITE_INDEX_CONSTRAINT_LIKE 65 7256#define SQLITE_INDEX_CONSTRAINT_GLOB 66 7257#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 7258#define SQLITE_INDEX_CONSTRAINT_NE 68 7259#define SQLITE_INDEX_CONSTRAINT_ISNOT 69 7260#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 7261#define SQLITE_INDEX_CONSTRAINT_ISNULL 71 7262#define SQLITE_INDEX_CONSTRAINT_IS 72 7263#define SQLITE_INDEX_CONSTRAINT_LIMIT 73 7264#define SQLITE_INDEX_CONSTRAINT_OFFSET 74 7265#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 7266 7267/* 7268** CAPI3REF: Register A Virtual Table Implementation 7269** METHOD: sqlite3 7270** 7271** ^These routines are used to register a new [virtual table module] name. 7272** ^Module names must be registered before 7273** creating a new [virtual table] using the module and before using a 7274** preexisting [virtual table] for the module. 7275** 7276** ^The module name is registered on the [database connection] specified 7277** by the first parameter. ^The name of the module is given by the 7278** second parameter. ^The third parameter is a pointer to 7279** the implementation of the [virtual table module]. ^The fourth 7280** parameter is an arbitrary client data pointer that is passed through 7281** into the [xCreate] and [xConnect] methods of the virtual table module 7282** when a new virtual table is be being created or reinitialized. 7283** 7284** ^The sqlite3_create_module_v2() interface has a fifth parameter which 7285** is a pointer to a destructor for the pClientData. ^SQLite will 7286** invoke the destructor function (if it is not NULL) when SQLite 7287** no longer needs the pClientData pointer. ^The destructor will also 7288** be invoked if the call to sqlite3_create_module_v2() fails. 7289** ^The sqlite3_create_module() 7290** interface is equivalent to sqlite3_create_module_v2() with a NULL 7291** destructor. 7292** 7293** ^If the third parameter (the pointer to the sqlite3_module object) is 7294** NULL then no new module is created and any existing modules with the 7295** same name are dropped. 7296** 7297** See also: [sqlite3_drop_modules()] 7298*/ 7299int sqlite3_create_module( 7300 sqlite3 *db, /* SQLite connection to register module with */ 7301 const char *zName, /* Name of the module */ 7302 const sqlite3_module *p, /* Methods for the module */ 7303 void *pClientData /* Client data for xCreate/xConnect */ 7304); 7305int sqlite3_create_module_v2( 7306 sqlite3 *db, /* SQLite connection to register module with */ 7307 const char *zName, /* Name of the module */ 7308 const sqlite3_module *p, /* Methods for the module */ 7309 void *pClientData, /* Client data for xCreate/xConnect */ 7310 void(*xDestroy)(void*) /* Module destructor function */ 7311); 7312 7313/* 7314** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7315** METHOD: sqlite3 7316** 7317** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7318** table modules from database connection D except those named on list L. 7319** The L parameter must be either NULL or a pointer to an array of pointers 7320** to strings where the array is terminated by a single NULL pointer. 7321** ^If the L parameter is NULL, then all virtual table modules are removed. 7322** 7323** See also: [sqlite3_create_module()] 7324*/ 7325int sqlite3_drop_modules( 7326 sqlite3 *db, /* Remove modules from this connection */ 7327 const char **azKeep /* Except, do not remove the ones named here */ 7328); 7329 7330/* 7331** CAPI3REF: Virtual Table Instance Object 7332** KEYWORDS: sqlite3_vtab 7333** 7334** Every [virtual table module] implementation uses a subclass 7335** of this object to describe a particular instance 7336** of the [virtual table]. Each subclass will 7337** be tailored to the specific needs of the module implementation. 7338** The purpose of this superclass is to define certain fields that are 7339** common to all module implementations. 7340** 7341** ^Virtual tables methods can set an error message by assigning a 7342** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 7343** take care that any prior string is freed by a call to [sqlite3_free()] 7344** prior to assigning a new string to zErrMsg. ^After the error message 7345** is delivered up to the client application, the string will be automatically 7346** freed by sqlite3_free() and the zErrMsg field will be zeroed. 7347*/ 7348struct sqlite3_vtab { 7349 const sqlite3_module *pModule; /* The module for this virtual table */ 7350 int nRef; /* Number of open cursors */ 7351 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 7352 /* Virtual table implementations will typically add additional fields */ 7353}; 7354 7355/* 7356** CAPI3REF: Virtual Table Cursor Object 7357** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 7358** 7359** Every [virtual table module] implementation uses a subclass of the 7360** following structure to describe cursors that point into the 7361** [virtual table] and are used 7362** to loop through the virtual table. Cursors are created using the 7363** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 7364** by the [sqlite3_module.xClose | xClose] method. Cursors are used 7365** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 7366** of the module. Each module implementation will define 7367** the content of a cursor structure to suit its own needs. 7368** 7369** This superclass exists in order to define fields of the cursor that 7370** are common to all implementations. 7371*/ 7372struct sqlite3_vtab_cursor { 7373 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 7374 /* Virtual table implementations will typically add additional fields */ 7375}; 7376 7377/* 7378** CAPI3REF: Declare The Schema Of A Virtual Table 7379** 7380** ^The [xCreate] and [xConnect] methods of a 7381** [virtual table module] call this interface 7382** to declare the format (the names and datatypes of the columns) of 7383** the virtual tables they implement. 7384*/ 7385int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 7386 7387/* 7388** CAPI3REF: Overload A Function For A Virtual Table 7389** METHOD: sqlite3 7390** 7391** ^(Virtual tables can provide alternative implementations of functions 7392** using the [xFindFunction] method of the [virtual table module]. 7393** But global versions of those functions 7394** must exist in order to be overloaded.)^ 7395** 7396** ^(This API makes sure a global version of a function with a particular 7397** name and number of parameters exists. If no such function exists 7398** before this API is called, a new function is created.)^ ^The implementation 7399** of the new function always causes an exception to be thrown. So 7400** the new function is not good for anything by itself. Its only 7401** purpose is to be a placeholder function that can be overloaded 7402** by a [virtual table]. 7403*/ 7404int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 7405 7406/* 7407** The interface to the virtual-table mechanism defined above (back up 7408** to a comment remarkably similar to this one) is currently considered 7409** to be experimental. The interface might change in incompatible ways. 7410** If this is a problem for you, do not use the interface at this time. 7411** 7412** When the virtual-table mechanism stabilizes, we will declare the 7413** interface fixed, support it indefinitely, and remove this comment. 7414*/ 7415 7416/* 7417** CAPI3REF: A Handle To An Open BLOB 7418** KEYWORDS: {BLOB handle} {BLOB handles} 7419** 7420** An instance of this object represents an open BLOB on which 7421** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 7422** ^Objects of this type are created by [sqlite3_blob_open()] 7423** and destroyed by [sqlite3_blob_close()]. 7424** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 7425** can be used to read or write small subsections of the BLOB. 7426** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 7427*/ 7428typedef struct sqlite3_blob sqlite3_blob; 7429 7430/* 7431** CAPI3REF: Open A BLOB For Incremental I/O 7432** METHOD: sqlite3 7433** CONSTRUCTOR: sqlite3_blob 7434** 7435** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 7436** in row iRow, column zColumn, table zTable in database zDb; 7437** in other words, the same BLOB that would be selected by: 7438** 7439** <pre> 7440** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7441** </pre>)^ 7442** 7443** ^(Parameter zDb is not the filename that contains the database, but 7444** rather the symbolic name of the database. For attached databases, this is 7445** the name that appears after the AS keyword in the [ATTACH] statement. 7446** For the main database file, the database name is "main". For TEMP 7447** tables, the database name is "temp".)^ 7448** 7449** ^If the flags parameter is non-zero, then the BLOB is opened for read 7450** and write access. ^If the flags parameter is zero, the BLOB is opened for 7451** read-only access. 7452** 7453** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7454** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7455** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7456** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7457** on *ppBlob after this function it returns. 7458** 7459** This function fails with SQLITE_ERROR if any of the following are true: 7460** <ul> 7461** <li> ^(Database zDb does not exist)^, 7462** <li> ^(Table zTable does not exist within database zDb)^, 7463** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7464** <li> ^(Column zColumn does not exist)^, 7465** <li> ^(Row iRow is not present in the table)^, 7466** <li> ^(The specified column of row iRow contains a value that is not 7467** a TEXT or BLOB value)^, 7468** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7469** constraint and the blob is being opened for read/write access)^, 7470** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7471** column zColumn is part of a [child key] definition and the blob is 7472** being opened for read/write access)^. 7473** </ul> 7474** 7475** ^Unless it returns SQLITE_MISUSE, this function sets the 7476** [database connection] error code and message accessible via 7477** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7478** 7479** A BLOB referenced by sqlite3_blob_open() may be read using the 7480** [sqlite3_blob_read()] interface and modified by using 7481** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7482** different row of the same table using the [sqlite3_blob_reopen()] 7483** interface. However, the column, table, or database of a [BLOB handle] 7484** cannot be changed after the [BLOB handle] is opened. 7485** 7486** ^(If the row that a BLOB handle points to is modified by an 7487** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7488** then the BLOB handle is marked as "expired". 7489** This is true if any column of the row is changed, even a column 7490** other than the one the BLOB handle is open on.)^ 7491** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7492** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7493** ^(Changes written into a BLOB prior to the BLOB expiring are not 7494** rolled back by the expiration of the BLOB. Such changes will eventually 7495** commit if the transaction continues to completion.)^ 7496** 7497** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7498** the opened blob. ^The size of a blob may not be changed by this 7499** interface. Use the [UPDATE] SQL command to change the size of a 7500** blob. 7501** 7502** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7503** and the built-in [zeroblob] SQL function may be used to create a 7504** zero-filled blob to read or write using the incremental-blob interface. 7505** 7506** To avoid a resource leak, every open [BLOB handle] should eventually 7507** be released by a call to [sqlite3_blob_close()]. 7508** 7509** See also: [sqlite3_blob_close()], 7510** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7511** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7512*/ 7513int sqlite3_blob_open( 7514 sqlite3*, 7515 const char *zDb, 7516 const char *zTable, 7517 const char *zColumn, 7518 sqlite3_int64 iRow, 7519 int flags, 7520 sqlite3_blob **ppBlob 7521); 7522 7523/* 7524** CAPI3REF: Move a BLOB Handle to a New Row 7525** METHOD: sqlite3_blob 7526** 7527** ^This function is used to move an existing [BLOB handle] so that it points 7528** to a different row of the same database table. ^The new row is identified 7529** by the rowid value passed as the second argument. Only the row can be 7530** changed. ^The database, table and column on which the blob handle is open 7531** remain the same. Moving an existing [BLOB handle] to a new row is 7532** faster than closing the existing handle and opening a new one. 7533** 7534** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7535** it must exist and there must be either a blob or text value stored in 7536** the nominated column.)^ ^If the new row is not present in the table, or if 7537** it does not contain a blob or text value, or if another error occurs, an 7538** SQLite error code is returned and the blob handle is considered aborted. 7539** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7540** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7541** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7542** always returns zero. 7543** 7544** ^This function sets the database handle error code and message. 7545*/ 7546int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7547 7548/* 7549** CAPI3REF: Close A BLOB Handle 7550** DESTRUCTOR: sqlite3_blob 7551** 7552** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7553** unconditionally. Even if this routine returns an error code, the 7554** handle is still closed.)^ 7555** 7556** ^If the blob handle being closed was opened for read-write access, and if 7557** the database is in auto-commit mode and there are no other open read-write 7558** blob handles or active write statements, the current transaction is 7559** committed. ^If an error occurs while committing the transaction, an error 7560** code is returned and the transaction rolled back. 7561** 7562** Calling this function with an argument that is not a NULL pointer or an 7563** open blob handle results in undefined behaviour. ^Calling this routine 7564** with a null pointer (such as would be returned by a failed call to 7565** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7566** is passed a valid open blob handle, the values returned by the 7567** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7568*/ 7569int sqlite3_blob_close(sqlite3_blob *); 7570 7571/* 7572** CAPI3REF: Return The Size Of An Open BLOB 7573** METHOD: sqlite3_blob 7574** 7575** ^Returns the size in bytes of the BLOB accessible via the 7576** successfully opened [BLOB handle] in its only argument. ^The 7577** incremental blob I/O routines can only read or overwriting existing 7578** blob content; they cannot change the size of a blob. 7579** 7580** This routine only works on a [BLOB handle] which has been created 7581** by a prior successful call to [sqlite3_blob_open()] and which has not 7582** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7583** to this routine results in undefined and probably undesirable behavior. 7584*/ 7585int sqlite3_blob_bytes(sqlite3_blob *); 7586 7587/* 7588** CAPI3REF: Read Data From A BLOB Incrementally 7589** METHOD: sqlite3_blob 7590** 7591** ^(This function is used to read data from an open [BLOB handle] into a 7592** caller-supplied buffer. N bytes of data are copied into buffer Z 7593** from the open BLOB, starting at offset iOffset.)^ 7594** 7595** ^If offset iOffset is less than N bytes from the end of the BLOB, 7596** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7597** less than zero, [SQLITE_ERROR] is returned and no data is read. 7598** ^The size of the blob (and hence the maximum value of N+iOffset) 7599** can be determined using the [sqlite3_blob_bytes()] interface. 7600** 7601** ^An attempt to read from an expired [BLOB handle] fails with an 7602** error code of [SQLITE_ABORT]. 7603** 7604** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7605** Otherwise, an [error code] or an [extended error code] is returned.)^ 7606** 7607** This routine only works on a [BLOB handle] which has been created 7608** by a prior successful call to [sqlite3_blob_open()] and which has not 7609** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7610** to this routine results in undefined and probably undesirable behavior. 7611** 7612** See also: [sqlite3_blob_write()]. 7613*/ 7614int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7615 7616/* 7617** CAPI3REF: Write Data Into A BLOB Incrementally 7618** METHOD: sqlite3_blob 7619** 7620** ^(This function is used to write data into an open [BLOB handle] from a 7621** caller-supplied buffer. N bytes of data are copied from the buffer Z 7622** into the open BLOB, starting at offset iOffset.)^ 7623** 7624** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7625** Otherwise, an [error code] or an [extended error code] is returned.)^ 7626** ^Unless SQLITE_MISUSE is returned, this function sets the 7627** [database connection] error code and message accessible via 7628** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7629** 7630** ^If the [BLOB handle] passed as the first argument was not opened for 7631** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7632** this function returns [SQLITE_READONLY]. 7633** 7634** This function may only modify the contents of the BLOB; it is 7635** not possible to increase the size of a BLOB using this API. 7636** ^If offset iOffset is less than N bytes from the end of the BLOB, 7637** [SQLITE_ERROR] is returned and no data is written. The size of the 7638** BLOB (and hence the maximum value of N+iOffset) can be determined 7639** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7640** than zero [SQLITE_ERROR] is returned and no data is written. 7641** 7642** ^An attempt to write to an expired [BLOB handle] fails with an 7643** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7644** before the [BLOB handle] expired are not rolled back by the 7645** expiration of the handle, though of course those changes might 7646** have been overwritten by the statement that expired the BLOB handle 7647** or by other independent statements. 7648** 7649** This routine only works on a [BLOB handle] which has been created 7650** by a prior successful call to [sqlite3_blob_open()] and which has not 7651** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7652** to this routine results in undefined and probably undesirable behavior. 7653** 7654** See also: [sqlite3_blob_read()]. 7655*/ 7656int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7657 7658/* 7659** CAPI3REF: Virtual File System Objects 7660** 7661** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7662** that SQLite uses to interact 7663** with the underlying operating system. Most SQLite builds come with a 7664** single default VFS that is appropriate for the host computer. 7665** New VFSes can be registered and existing VFSes can be unregistered. 7666** The following interfaces are provided. 7667** 7668** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7669** ^Names are case sensitive. 7670** ^Names are zero-terminated UTF-8 strings. 7671** ^If there is no match, a NULL pointer is returned. 7672** ^If zVfsName is NULL then the default VFS is returned. 7673** 7674** ^New VFSes are registered with sqlite3_vfs_register(). 7675** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7676** ^The same VFS can be registered multiple times without injury. 7677** ^To make an existing VFS into the default VFS, register it again 7678** with the makeDflt flag set. If two different VFSes with the 7679** same name are registered, the behavior is undefined. If a 7680** VFS is registered with a name that is NULL or an empty string, 7681** then the behavior is undefined. 7682** 7683** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7684** ^(If the default VFS is unregistered, another VFS is chosen as 7685** the default. The choice for the new VFS is arbitrary.)^ 7686*/ 7687sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7688int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7689int sqlite3_vfs_unregister(sqlite3_vfs*); 7690 7691/* 7692** CAPI3REF: Mutexes 7693** 7694** The SQLite core uses these routines for thread 7695** synchronization. Though they are intended for internal 7696** use by SQLite, code that links against SQLite is 7697** permitted to use any of these routines. 7698** 7699** The SQLite source code contains multiple implementations 7700** of these mutex routines. An appropriate implementation 7701** is selected automatically at compile-time. The following 7702** implementations are available in the SQLite core: 7703** 7704** <ul> 7705** <li> SQLITE_MUTEX_PTHREADS 7706** <li> SQLITE_MUTEX_W32 7707** <li> SQLITE_MUTEX_NOOP 7708** </ul> 7709** 7710** The SQLITE_MUTEX_NOOP implementation is a set of routines 7711** that does no real locking and is appropriate for use in 7712** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7713** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7714** and Windows. 7715** 7716** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7717** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7718** implementation is included with the library. In this case the 7719** application must supply a custom mutex implementation using the 7720** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7721** before calling sqlite3_initialize() or any other public sqlite3_ 7722** function that calls sqlite3_initialize(). 7723** 7724** ^The sqlite3_mutex_alloc() routine allocates a new 7725** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 7726** routine returns NULL if it is unable to allocate the requested 7727** mutex. The argument to sqlite3_mutex_alloc() must one of these 7728** integer constants: 7729** 7730** <ul> 7731** <li> SQLITE_MUTEX_FAST 7732** <li> SQLITE_MUTEX_RECURSIVE 7733** <li> SQLITE_MUTEX_STATIC_MAIN 7734** <li> SQLITE_MUTEX_STATIC_MEM 7735** <li> SQLITE_MUTEX_STATIC_OPEN 7736** <li> SQLITE_MUTEX_STATIC_PRNG 7737** <li> SQLITE_MUTEX_STATIC_LRU 7738** <li> SQLITE_MUTEX_STATIC_PMEM 7739** <li> SQLITE_MUTEX_STATIC_APP1 7740** <li> SQLITE_MUTEX_STATIC_APP2 7741** <li> SQLITE_MUTEX_STATIC_APP3 7742** <li> SQLITE_MUTEX_STATIC_VFS1 7743** <li> SQLITE_MUTEX_STATIC_VFS2 7744** <li> SQLITE_MUTEX_STATIC_VFS3 7745** </ul> 7746** 7747** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 7748** cause sqlite3_mutex_alloc() to create 7749** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 7750** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 7751** The mutex implementation does not need to make a distinction 7752** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 7753** not want to. SQLite will only request a recursive mutex in 7754** cases where it really needs one. If a faster non-recursive mutex 7755** implementation is available on the host platform, the mutex subsystem 7756** might return such a mutex in response to SQLITE_MUTEX_FAST. 7757** 7758** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 7759** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 7760** a pointer to a static preexisting mutex. ^Nine static mutexes are 7761** used by the current version of SQLite. Future versions of SQLite 7762** may add additional static mutexes. Static mutexes are for internal 7763** use by SQLite only. Applications that use SQLite mutexes should 7764** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 7765** SQLITE_MUTEX_RECURSIVE. 7766** 7767** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 7768** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 7769** returns a different mutex on every call. ^For the static 7770** mutex types, the same mutex is returned on every call that has 7771** the same type number. 7772** 7773** ^The sqlite3_mutex_free() routine deallocates a previously 7774** allocated dynamic mutex. Attempting to deallocate a static 7775** mutex results in undefined behavior. 7776** 7777** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 7778** to enter a mutex. ^If another thread is already within the mutex, 7779** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 7780** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 7781** upon successful entry. ^(Mutexes created using 7782** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 7783** In such cases, the 7784** mutex must be exited an equal number of times before another thread 7785** can enter.)^ If the same thread tries to enter any mutex other 7786** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 7787** 7788** ^(Some systems (for example, Windows 95) do not support the operation 7789** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 7790** will always return SQLITE_BUSY. The SQLite core only ever uses 7791** sqlite3_mutex_try() as an optimization so this is acceptable 7792** behavior.)^ 7793** 7794** ^The sqlite3_mutex_leave() routine exits a mutex that was 7795** previously entered by the same thread. The behavior 7796** is undefined if the mutex is not currently entered by the 7797** calling thread or is not currently allocated. 7798** 7799** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 7800** sqlite3_mutex_leave() is a NULL pointer, then all three routines 7801** behave as no-ops. 7802** 7803** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 7804*/ 7805sqlite3_mutex *sqlite3_mutex_alloc(int); 7806void sqlite3_mutex_free(sqlite3_mutex*); 7807void sqlite3_mutex_enter(sqlite3_mutex*); 7808int sqlite3_mutex_try(sqlite3_mutex*); 7809void sqlite3_mutex_leave(sqlite3_mutex*); 7810 7811/* 7812** CAPI3REF: Mutex Methods Object 7813** 7814** An instance of this structure defines the low-level routines 7815** used to allocate and use mutexes. 7816** 7817** Usually, the default mutex implementations provided by SQLite are 7818** sufficient, however the application has the option of substituting a custom 7819** implementation for specialized deployments or systems for which SQLite 7820** does not provide a suitable implementation. In this case, the application 7821** creates and populates an instance of this structure to pass 7822** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 7823** Additionally, an instance of this structure can be used as an 7824** output variable when querying the system for the current mutex 7825** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 7826** 7827** ^The xMutexInit method defined by this structure is invoked as 7828** part of system initialization by the sqlite3_initialize() function. 7829** ^The xMutexInit routine is called by SQLite exactly once for each 7830** effective call to [sqlite3_initialize()]. 7831** 7832** ^The xMutexEnd method defined by this structure is invoked as 7833** part of system shutdown by the sqlite3_shutdown() function. The 7834** implementation of this method is expected to release all outstanding 7835** resources obtained by the mutex methods implementation, especially 7836** those obtained by the xMutexInit method. ^The xMutexEnd() 7837** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 7838** 7839** ^(The remaining seven methods defined by this structure (xMutexAlloc, 7840** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 7841** xMutexNotheld) implement the following interfaces (respectively): 7842** 7843** <ul> 7844** <li> [sqlite3_mutex_alloc()] </li> 7845** <li> [sqlite3_mutex_free()] </li> 7846** <li> [sqlite3_mutex_enter()] </li> 7847** <li> [sqlite3_mutex_try()] </li> 7848** <li> [sqlite3_mutex_leave()] </li> 7849** <li> [sqlite3_mutex_held()] </li> 7850** <li> [sqlite3_mutex_notheld()] </li> 7851** </ul>)^ 7852** 7853** The only difference is that the public sqlite3_XXX functions enumerated 7854** above silently ignore any invocations that pass a NULL pointer instead 7855** of a valid mutex handle. The implementations of the methods defined 7856** by this structure are not required to handle this case. The results 7857** of passing a NULL pointer instead of a valid mutex handle are undefined 7858** (i.e. it is acceptable to provide an implementation that segfaults if 7859** it is passed a NULL pointer). 7860** 7861** The xMutexInit() method must be threadsafe. It must be harmless to 7862** invoke xMutexInit() multiple times within the same process and without 7863** intervening calls to xMutexEnd(). Second and subsequent calls to 7864** xMutexInit() must be no-ops. 7865** 7866** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 7867** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 7868** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 7869** memory allocation for a fast or recursive mutex. 7870** 7871** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 7872** called, but only if the prior call to xMutexInit returned SQLITE_OK. 7873** If xMutexInit fails in any way, it is expected to clean up after itself 7874** prior to returning. 7875*/ 7876typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 7877struct sqlite3_mutex_methods { 7878 int (*xMutexInit)(void); 7879 int (*xMutexEnd)(void); 7880 sqlite3_mutex *(*xMutexAlloc)(int); 7881 void (*xMutexFree)(sqlite3_mutex *); 7882 void (*xMutexEnter)(sqlite3_mutex *); 7883 int (*xMutexTry)(sqlite3_mutex *); 7884 void (*xMutexLeave)(sqlite3_mutex *); 7885 int (*xMutexHeld)(sqlite3_mutex *); 7886 int (*xMutexNotheld)(sqlite3_mutex *); 7887}; 7888 7889/* 7890** CAPI3REF: Mutex Verification Routines 7891** 7892** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 7893** are intended for use inside assert() statements. The SQLite core 7894** never uses these routines except inside an assert() and applications 7895** are advised to follow the lead of the core. The SQLite core only 7896** provides implementations for these routines when it is compiled 7897** with the SQLITE_DEBUG flag. External mutex implementations 7898** are only required to provide these routines if SQLITE_DEBUG is 7899** defined and if NDEBUG is not defined. 7900** 7901** These routines should return true if the mutex in their argument 7902** is held or not held, respectively, by the calling thread. 7903** 7904** The implementation is not required to provide versions of these 7905** routines that actually work. If the implementation does not provide working 7906** versions of these routines, it should at least provide stubs that always 7907** return true so that one does not get spurious assertion failures. 7908** 7909** If the argument to sqlite3_mutex_held() is a NULL pointer then 7910** the routine should return 1. This seems counter-intuitive since 7911** clearly the mutex cannot be held if it does not exist. But 7912** the reason the mutex does not exist is because the build is not 7913** using mutexes. And we do not want the assert() containing the 7914** call to sqlite3_mutex_held() to fail, so a non-zero return is 7915** the appropriate thing to do. The sqlite3_mutex_notheld() 7916** interface should also return 1 when given a NULL pointer. 7917*/ 7918#ifndef NDEBUG 7919int sqlite3_mutex_held(sqlite3_mutex*); 7920int sqlite3_mutex_notheld(sqlite3_mutex*); 7921#endif 7922 7923/* 7924** CAPI3REF: Mutex Types 7925** 7926** The [sqlite3_mutex_alloc()] interface takes a single argument 7927** which is one of these integer constants. 7928** 7929** The set of static mutexes may change from one SQLite release to the 7930** next. Applications that override the built-in mutex logic must be 7931** prepared to accommodate additional static mutexes. 7932*/ 7933#define SQLITE_MUTEX_FAST 0 7934#define SQLITE_MUTEX_RECURSIVE 1 7935#define SQLITE_MUTEX_STATIC_MAIN 2 7936#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 7937#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 7938#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 7939#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 7940#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 7941#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 7942#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 7943#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 7944#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 7945#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 7946#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 7947#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 7948#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 7949 7950/* Legacy compatibility: */ 7951#define SQLITE_MUTEX_STATIC_MASTER 2 7952 7953 7954/* 7955** CAPI3REF: Retrieve the mutex for a database connection 7956** METHOD: sqlite3 7957** 7958** ^This interface returns a pointer the [sqlite3_mutex] object that 7959** serializes access to the [database connection] given in the argument 7960** when the [threading mode] is Serialized. 7961** ^If the [threading mode] is Single-thread or Multi-thread then this 7962** routine returns a NULL pointer. 7963*/ 7964sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 7965 7966/* 7967** CAPI3REF: Low-Level Control Of Database Files 7968** METHOD: sqlite3 7969** KEYWORDS: {file control} 7970** 7971** ^The [sqlite3_file_control()] interface makes a direct call to the 7972** xFileControl method for the [sqlite3_io_methods] object associated 7973** with a particular database identified by the second argument. ^The 7974** name of the database is "main" for the main database or "temp" for the 7975** TEMP database, or the name that appears after the AS keyword for 7976** databases that are added using the [ATTACH] SQL command. 7977** ^A NULL pointer can be used in place of "main" to refer to the 7978** main database file. 7979** ^The third and fourth parameters to this routine 7980** are passed directly through to the second and third parameters of 7981** the xFileControl method. ^The return value of the xFileControl 7982** method becomes the return value of this routine. 7983** 7984** A few opcodes for [sqlite3_file_control()] are handled directly 7985** by the SQLite core and never invoke the 7986** sqlite3_io_methods.xFileControl method. 7987** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 7988** a pointer to the underlying [sqlite3_file] object to be written into 7989** the space pointed to by the 4th parameter. The 7990** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 7991** the [sqlite3_file] object associated with the journal file instead of 7992** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 7993** a pointer to the underlying [sqlite3_vfs] object for the file. 7994** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 7995** from the pager. 7996** 7997** ^If the second parameter (zDbName) does not match the name of any 7998** open database file, then SQLITE_ERROR is returned. ^This error 7999** code is not remembered and will not be recalled by [sqlite3_errcode()] 8000** or [sqlite3_errmsg()]. The underlying xFileControl method might 8001** also return SQLITE_ERROR. There is no way to distinguish between 8002** an incorrect zDbName and an SQLITE_ERROR return from the underlying 8003** xFileControl method. 8004** 8005** See also: [file control opcodes] 8006*/ 8007int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 8008 8009/* 8010** CAPI3REF: Testing Interface 8011** 8012** ^The sqlite3_test_control() interface is used to read out internal 8013** state of SQLite and to inject faults into SQLite for testing 8014** purposes. ^The first parameter is an operation code that determines 8015** the number, meaning, and operation of all subsequent parameters. 8016** 8017** This interface is not for use by applications. It exists solely 8018** for verifying the correct operation of the SQLite library. Depending 8019** on how the SQLite library is compiled, this interface might not exist. 8020** 8021** The details of the operation codes, their meanings, the parameters 8022** they take, and what they do are all subject to change without notice. 8023** Unlike most of the SQLite API, this function is not guaranteed to 8024** operate consistently from one release to the next. 8025*/ 8026int sqlite3_test_control(int op, ...); 8027 8028/* 8029** CAPI3REF: Testing Interface Operation Codes 8030** 8031** These constants are the valid operation code parameters used 8032** as the first argument to [sqlite3_test_control()]. 8033** 8034** These parameters and their meanings are subject to change 8035** without notice. These values are for testing purposes only. 8036** Applications should not use any of these parameters or the 8037** [sqlite3_test_control()] interface. 8038*/ 8039#define SQLITE_TESTCTRL_FIRST 5 8040#define SQLITE_TESTCTRL_PRNG_SAVE 5 8041#define SQLITE_TESTCTRL_PRNG_RESTORE 6 8042#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 8043#define SQLITE_TESTCTRL_BITVEC_TEST 8 8044#define SQLITE_TESTCTRL_FAULT_INSTALL 9 8045#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 8046#define SQLITE_TESTCTRL_PENDING_BYTE 11 8047#define SQLITE_TESTCTRL_ASSERT 12 8048#define SQLITE_TESTCTRL_ALWAYS 13 8049#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 8050#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 8051#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 8052#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 8053#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 8054#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 8055#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 8056#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 8057#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 8058#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 8059#define SQLITE_TESTCTRL_BYTEORDER 22 8060#define SQLITE_TESTCTRL_ISINIT 23 8061#define SQLITE_TESTCTRL_SORTER_MMAP 24 8062#define SQLITE_TESTCTRL_IMPOSTER 25 8063#define SQLITE_TESTCTRL_PARSER_COVERAGE 26 8064#define SQLITE_TESTCTRL_RESULT_INTREAL 27 8065#define SQLITE_TESTCTRL_PRNG_SEED 28 8066#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 8067#define SQLITE_TESTCTRL_SEEK_COUNT 30 8068#define SQLITE_TESTCTRL_TRACEFLAGS 31 8069#define SQLITE_TESTCTRL_TUNE 32 8070#define SQLITE_TESTCTRL_LOGEST 33 8071#define SQLITE_TESTCTRL_LAST 33 /* Largest TESTCTRL */ 8072 8073/* 8074** CAPI3REF: SQL Keyword Checking 8075** 8076** These routines provide access to the set of SQL language keywords 8077** recognized by SQLite. Applications can uses these routines to determine 8078** whether or not a specific identifier needs to be escaped (for example, 8079** by enclosing in double-quotes) so as not to confuse the parser. 8080** 8081** The sqlite3_keyword_count() interface returns the number of distinct 8082** keywords understood by SQLite. 8083** 8084** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and 8085** makes *Z point to that keyword expressed as UTF8 and writes the number 8086** of bytes in the keyword into *L. The string that *Z points to is not 8087** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 8088** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 8089** or L are NULL or invalid pointers then calls to 8090** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 8091** 8092** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 8093** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 8094** if it is and zero if not. 8095** 8096** The parser used by SQLite is forgiving. It is often possible to use 8097** a keyword as an identifier as long as such use does not result in a 8098** parsing ambiguity. For example, the statement 8099** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 8100** creates a new table named "BEGIN" with three columns named 8101** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 8102** using keywords as identifiers. Common techniques used to avoid keyword 8103** name collisions include: 8104** <ul> 8105** <li> Put all identifier names inside double-quotes. This is the official 8106** SQL way to escape identifier names. 8107** <li> Put identifier names inside [...]. This is not standard SQL, 8108** but it is what SQL Server does and so lots of programmers use this 8109** technique. 8110** <li> Begin every identifier with the letter "Z" as no SQL keywords start 8111** with "Z". 8112** <li> Include a digit somewhere in every identifier name. 8113** </ul> 8114** 8115** Note that the number of keywords understood by SQLite can depend on 8116** compile-time options. For example, "VACUUM" is not a keyword if 8117** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 8118** new keywords may be added to future releases of SQLite. 8119*/ 8120int sqlite3_keyword_count(void); 8121int sqlite3_keyword_name(int,const char**,int*); 8122int sqlite3_keyword_check(const char*,int); 8123 8124/* 8125** CAPI3REF: Dynamic String Object 8126** KEYWORDS: {dynamic string} 8127** 8128** An instance of the sqlite3_str object contains a dynamically-sized 8129** string under construction. 8130** 8131** The lifecycle of an sqlite3_str object is as follows: 8132** <ol> 8133** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 8134** <li> ^Text is appended to the sqlite3_str object using various 8135** methods, such as [sqlite3_str_appendf()]. 8136** <li> ^The sqlite3_str object is destroyed and the string it created 8137** is returned using the [sqlite3_str_finish()] interface. 8138** </ol> 8139*/ 8140typedef struct sqlite3_str sqlite3_str; 8141 8142/* 8143** CAPI3REF: Create A New Dynamic String Object 8144** CONSTRUCTOR: sqlite3_str 8145** 8146** ^The [sqlite3_str_new(D)] interface allocates and initializes 8147** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 8148** [sqlite3_str_new()] must be freed by a subsequent call to 8149** [sqlite3_str_finish(X)]. 8150** 8151** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 8152** valid [sqlite3_str] object, though in the event of an out-of-memory 8153** error the returned object might be a special singleton that will 8154** silently reject new text, always return SQLITE_NOMEM from 8155** [sqlite3_str_errcode()], always return 0 for 8156** [sqlite3_str_length()], and always return NULL from 8157** [sqlite3_str_finish(X)]. It is always safe to use the value 8158** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 8159** to any of the other [sqlite3_str] methods. 8160** 8161** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 8162** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 8163** length of the string contained in the [sqlite3_str] object will be 8164** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 8165** of [SQLITE_MAX_LENGTH]. 8166*/ 8167sqlite3_str *sqlite3_str_new(sqlite3*); 8168 8169/* 8170** CAPI3REF: Finalize A Dynamic String 8171** DESTRUCTOR: sqlite3_str 8172** 8173** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 8174** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 8175** that contains the constructed string. The calling application should 8176** pass the returned value to [sqlite3_free()] to avoid a memory leak. 8177** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 8178** errors were encountered during construction of the string. ^The 8179** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 8180** string in [sqlite3_str] object X is zero bytes long. 8181*/ 8182char *sqlite3_str_finish(sqlite3_str*); 8183 8184/* 8185** CAPI3REF: Add Content To A Dynamic String 8186** METHOD: sqlite3_str 8187** 8188** These interfaces add content to an sqlite3_str object previously obtained 8189** from [sqlite3_str_new()]. 8190** 8191** ^The [sqlite3_str_appendf(X,F,...)] and 8192** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 8193** functionality of SQLite to append formatted text onto the end of 8194** [sqlite3_str] object X. 8195** 8196** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 8197** onto the end of the [sqlite3_str] object X. N must be non-negative. 8198** S must contain at least N non-zero bytes of content. To append a 8199** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 8200** method instead. 8201** 8202** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 8203** zero-terminated string S onto the end of [sqlite3_str] object X. 8204** 8205** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 8206** single-byte character C onto the end of [sqlite3_str] object X. 8207** ^This method can be used, for example, to add whitespace indentation. 8208** 8209** ^The [sqlite3_str_reset(X)] method resets the string under construction 8210** inside [sqlite3_str] object X back to zero bytes in length. 8211** 8212** These methods do not return a result code. ^If an error occurs, that fact 8213** is recorded in the [sqlite3_str] object and can be recovered by a 8214** subsequent call to [sqlite3_str_errcode(X)]. 8215*/ 8216void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 8217void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 8218void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 8219void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 8220void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 8221void sqlite3_str_reset(sqlite3_str*); 8222 8223/* 8224** CAPI3REF: Status Of A Dynamic String 8225** METHOD: sqlite3_str 8226** 8227** These interfaces return the current status of an [sqlite3_str] object. 8228** 8229** ^If any prior errors have occurred while constructing the dynamic string 8230** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 8231** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 8232** [SQLITE_NOMEM] following any out-of-memory error, or 8233** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 8234** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 8235** 8236** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 8237** of the dynamic string under construction in [sqlite3_str] object X. 8238** ^The length returned by [sqlite3_str_length(X)] does not include the 8239** zero-termination byte. 8240** 8241** ^The [sqlite3_str_value(X)] method returns a pointer to the current 8242** content of the dynamic string under construction in X. The value 8243** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 8244** and might be freed or altered by any subsequent method on the same 8245** [sqlite3_str] object. Applications must not used the pointer returned 8246** [sqlite3_str_value(X)] after any subsequent method call on the same 8247** object. ^Applications may change the content of the string returned 8248** by [sqlite3_str_value(X)] as long as they do not write into any bytes 8249** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 8250** write any byte after any subsequent sqlite3_str method call. 8251*/ 8252int sqlite3_str_errcode(sqlite3_str*); 8253int sqlite3_str_length(sqlite3_str*); 8254char *sqlite3_str_value(sqlite3_str*); 8255 8256/* 8257** CAPI3REF: SQLite Runtime Status 8258** 8259** ^These interfaces are used to retrieve runtime status information 8260** about the performance of SQLite, and optionally to reset various 8261** highwater marks. ^The first argument is an integer code for 8262** the specific parameter to measure. ^(Recognized integer codes 8263** are of the form [status parameters | SQLITE_STATUS_...].)^ 8264** ^The current value of the parameter is returned into *pCurrent. 8265** ^The highest recorded value is returned in *pHighwater. ^If the 8266** resetFlag is true, then the highest record value is reset after 8267** *pHighwater is written. ^(Some parameters do not record the highest 8268** value. For those parameters 8269** nothing is written into *pHighwater and the resetFlag is ignored.)^ 8270** ^(Other parameters record only the highwater mark and not the current 8271** value. For these latter parameters nothing is written into *pCurrent.)^ 8272** 8273** ^The sqlite3_status() and sqlite3_status64() routines return 8274** SQLITE_OK on success and a non-zero [error code] on failure. 8275** 8276** If either the current value or the highwater mark is too large to 8277** be represented by a 32-bit integer, then the values returned by 8278** sqlite3_status() are undefined. 8279** 8280** See also: [sqlite3_db_status()] 8281*/ 8282int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 8283int sqlite3_status64( 8284 int op, 8285 sqlite3_int64 *pCurrent, 8286 sqlite3_int64 *pHighwater, 8287 int resetFlag 8288); 8289 8290 8291/* 8292** CAPI3REF: Status Parameters 8293** KEYWORDS: {status parameters} 8294** 8295** These integer constants designate various run-time status parameters 8296** that can be returned by [sqlite3_status()]. 8297** 8298** <dl> 8299** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8300** <dd>This parameter is the current amount of memory checked out 8301** using [sqlite3_malloc()], either directly or indirectly. The 8302** figure includes calls made to [sqlite3_malloc()] by the application 8303** and internal memory usage by the SQLite library. Auxiliary page-cache 8304** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8305** this parameter. The amount returned is the sum of the allocation 8306** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8307** 8308** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8309** <dd>This parameter records the largest memory allocation request 8310** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8311** internal equivalents). Only the value returned in the 8312** *pHighwater parameter to [sqlite3_status()] is of interest. 8313** The value written into the *pCurrent parameter is undefined.</dd>)^ 8314** 8315** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8316** <dd>This parameter records the number of separate memory allocations 8317** currently checked out.</dd>)^ 8318** 8319** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8320** <dd>This parameter returns the number of pages used out of the 8321** [pagecache memory allocator] that was configured using 8322** [SQLITE_CONFIG_PAGECACHE]. The 8323** value returned is in pages, not in bytes.</dd>)^ 8324** 8325** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8326** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8327** <dd>This parameter returns the number of bytes of page cache 8328** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8329** buffer and where forced to overflow to [sqlite3_malloc()]. The 8330** returned value includes allocations that overflowed because they 8331** where too large (they were larger than the "sz" parameter to 8332** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8333** no space was left in the page cache.</dd>)^ 8334** 8335** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 8336** <dd>This parameter records the largest memory allocation request 8337** handed to the [pagecache memory allocator]. Only the value returned in the 8338** *pHighwater parameter to [sqlite3_status()] is of interest. 8339** The value written into the *pCurrent parameter is undefined.</dd>)^ 8340** 8341** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 8342** <dd>No longer used.</dd> 8343** 8344** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 8345** <dd>No longer used.</dd> 8346** 8347** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 8348** <dd>No longer used.</dd> 8349** 8350** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 8351** <dd>The *pHighwater parameter records the deepest parser stack. 8352** The *pCurrent value is undefined. The *pHighwater value is only 8353** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 8354** </dl> 8355** 8356** New status parameters may be added from time to time. 8357*/ 8358#define SQLITE_STATUS_MEMORY_USED 0 8359#define SQLITE_STATUS_PAGECACHE_USED 1 8360#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 8361#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 8362#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 8363#define SQLITE_STATUS_MALLOC_SIZE 5 8364#define SQLITE_STATUS_PARSER_STACK 6 8365#define SQLITE_STATUS_PAGECACHE_SIZE 7 8366#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 8367#define SQLITE_STATUS_MALLOC_COUNT 9 8368 8369/* 8370** CAPI3REF: Database Connection Status 8371** METHOD: sqlite3 8372** 8373** ^This interface is used to retrieve runtime status information 8374** about a single [database connection]. ^The first argument is the 8375** database connection object to be interrogated. ^The second argument 8376** is an integer constant, taken from the set of 8377** [SQLITE_DBSTATUS options], that 8378** determines the parameter to interrogate. The set of 8379** [SQLITE_DBSTATUS options] is likely 8380** to grow in future releases of SQLite. 8381** 8382** ^The current value of the requested parameter is written into *pCur 8383** and the highest instantaneous value is written into *pHiwtr. ^If 8384** the resetFlg is true, then the highest instantaneous value is 8385** reset back down to the current value. 8386** 8387** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 8388** non-zero [error code] on failure. 8389** 8390** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 8391*/ 8392int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 8393 8394/* 8395** CAPI3REF: Status Parameters for database connections 8396** KEYWORDS: {SQLITE_DBSTATUS options} 8397** 8398** These constants are the available integer "verbs" that can be passed as 8399** the second argument to the [sqlite3_db_status()] interface. 8400** 8401** New verbs may be added in future releases of SQLite. Existing verbs 8402** might be discontinued. Applications should check the return code from 8403** [sqlite3_db_status()] to make sure that the call worked. 8404** The [sqlite3_db_status()] interface will return a non-zero error code 8405** if a discontinued or unsupported verb is invoked. 8406** 8407** <dl> 8408** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 8409** <dd>This parameter returns the number of lookaside memory slots currently 8410** checked out.</dd>)^ 8411** 8412** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 8413** <dd>This parameter returns the number of malloc attempts that were 8414** satisfied using lookaside memory. Only the high-water value is meaningful; 8415** the current value is always zero.)^ 8416** 8417** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 8418** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 8419** <dd>This parameter returns the number malloc attempts that might have 8420** been satisfied using lookaside memory but failed due to the amount of 8421** memory requested being larger than the lookaside slot size. 8422** Only the high-water value is meaningful; 8423** the current value is always zero.)^ 8424** 8425** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 8426** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 8427** <dd>This parameter returns the number malloc attempts that might have 8428** been satisfied using lookaside memory but failed due to all lookaside 8429** memory already being in use. 8430** Only the high-water value is meaningful; 8431** the current value is always zero.)^ 8432** 8433** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 8434** <dd>This parameter returns the approximate number of bytes of heap 8435** memory used by all pager caches associated with the database connection.)^ 8436** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 8437** 8438** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 8439** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 8440** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 8441** pager cache is shared between two or more connections the bytes of heap 8442** memory used by that pager cache is divided evenly between the attached 8443** connections.)^ In other words, if none of the pager caches associated 8444** with the database connection are shared, this request returns the same 8445** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8446** shared, the value returned by this call will be smaller than that returned 8447** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8448** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8449** 8450** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8451** <dd>This parameter returns the approximate number of bytes of heap 8452** memory used to store the schema for all databases associated 8453** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8454** ^The full amount of memory used by the schemas is reported, even if the 8455** schema memory is shared with other database connections due to 8456** [shared cache mode] being enabled. 8457** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8458** 8459** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8460** <dd>This parameter returns the approximate number of bytes of heap 8461** and lookaside memory used by all prepared statements associated with 8462** the database connection.)^ 8463** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8464** </dd> 8465** 8466** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8467** <dd>This parameter returns the number of pager cache hits that have 8468** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8469** is always 0. 8470** </dd> 8471** 8472** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8473** <dd>This parameter returns the number of pager cache misses that have 8474** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8475** is always 0. 8476** </dd> 8477** 8478** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8479** <dd>This parameter returns the number of dirty cache entries that have 8480** been written to disk. Specifically, the number of pages written to the 8481** wal file in wal mode databases, or the number of pages written to the 8482** database file in rollback mode databases. Any pages written as part of 8483** transaction rollback or database recovery operations are not included. 8484** If an IO or other error occurs while writing a page to disk, the effect 8485** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8486** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8487** </dd> 8488** 8489** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8490** <dd>This parameter returns the number of dirty cache entries that have 8491** been written to disk in the middle of a transaction due to the page 8492** cache overflowing. Transactions are more efficient if they are written 8493** to disk all at once. When pages spill mid-transaction, that introduces 8494** additional overhead. This parameter can be used help identify 8495** inefficiencies that can be resolved by increasing the cache size. 8496** </dd> 8497** 8498** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8499** <dd>This parameter returns zero for the current value if and only if 8500** all foreign key constraints (deferred or immediate) have been 8501** resolved.)^ ^The highwater mark is always 0. 8502** </dd> 8503** </dl> 8504*/ 8505#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8506#define SQLITE_DBSTATUS_CACHE_USED 1 8507#define SQLITE_DBSTATUS_SCHEMA_USED 2 8508#define SQLITE_DBSTATUS_STMT_USED 3 8509#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8510#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8511#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8512#define SQLITE_DBSTATUS_CACHE_HIT 7 8513#define SQLITE_DBSTATUS_CACHE_MISS 8 8514#define SQLITE_DBSTATUS_CACHE_WRITE 9 8515#define SQLITE_DBSTATUS_DEFERRED_FKS 10 8516#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8517#define SQLITE_DBSTATUS_CACHE_SPILL 12 8518#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8519 8520 8521/* 8522** CAPI3REF: Prepared Statement Status 8523** METHOD: sqlite3_stmt 8524** 8525** ^(Each prepared statement maintains various 8526** [SQLITE_STMTSTATUS counters] that measure the number 8527** of times it has performed specific operations.)^ These counters can 8528** be used to monitor the performance characteristics of the prepared 8529** statements. For example, if the number of table steps greatly exceeds 8530** the number of table searches or result rows, that would tend to indicate 8531** that the prepared statement is using a full table scan rather than 8532** an index. 8533** 8534** ^(This interface is used to retrieve and reset counter values from 8535** a [prepared statement]. The first argument is the prepared statement 8536** object to be interrogated. The second argument 8537** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8538** to be interrogated.)^ 8539** ^The current value of the requested counter is returned. 8540** ^If the resetFlg is true, then the counter is reset to zero after this 8541** interface call returns. 8542** 8543** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8544*/ 8545int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8546 8547/* 8548** CAPI3REF: Status Parameters for prepared statements 8549** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8550** 8551** These preprocessor macros define integer codes that name counter 8552** values associated with the [sqlite3_stmt_status()] interface. 8553** The meanings of the various counters are as follows: 8554** 8555** <dl> 8556** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8557** <dd>^This is the number of times that SQLite has stepped forward in 8558** a table as part of a full table scan. Large numbers for this counter 8559** may indicate opportunities for performance improvement through 8560** careful use of indices.</dd> 8561** 8562** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8563** <dd>^This is the number of sort operations that have occurred. 8564** A non-zero value in this counter may indicate an opportunity to 8565** improvement performance through careful use of indices.</dd> 8566** 8567** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8568** <dd>^This is the number of rows inserted into transient indices that 8569** were created automatically in order to help joins run faster. 8570** A non-zero value in this counter may indicate an opportunity to 8571** improvement performance by adding permanent indices that do not 8572** need to be reinitialized each time the statement is run.</dd> 8573** 8574** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8575** <dd>^This is the number of virtual machine operations executed 8576** by the prepared statement if that number is less than or equal 8577** to 2147483647. The number of virtual machine operations can be 8578** used as a proxy for the total work done by the prepared statement. 8579** If the number of virtual machine operations exceeds 2147483647 8580** then the value returned by this statement status code is undefined. 8581** 8582** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8583** <dd>^This is the number of times that the prepare statement has been 8584** automatically regenerated due to schema changes or changes to 8585** [bound parameters] that might affect the query plan. 8586** 8587** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8588** <dd>^This is the number of times that the prepared statement has 8589** been run. A single "run" for the purposes of this counter is one 8590** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8591** The counter is incremented on the first [sqlite3_step()] call of each 8592** cycle. 8593** 8594** [[SQLITE_STMTSTATUS_FILTER_MISS]] 8595** [[SQLITE_STMTSTATUS_FILTER HIT]] 8596** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br> 8597** SQLITE_STMTSTATUS_FILTER_MISS</dt> 8598** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join 8599** step was bypassed because a Bloom filter returned not-found. The 8600** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of 8601** times that the Bloom filter returned a find, and thus the join step 8602** had to be processed as normal. 8603** 8604** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8605** <dd>^This is the approximate number of bytes of heap memory 8606** used to store the prepared statement. ^This value is not actually 8607** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8608** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8609** </dd> 8610** </dl> 8611*/ 8612#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8613#define SQLITE_STMTSTATUS_SORT 2 8614#define SQLITE_STMTSTATUS_AUTOINDEX 3 8615#define SQLITE_STMTSTATUS_VM_STEP 4 8616#define SQLITE_STMTSTATUS_REPREPARE 5 8617#define SQLITE_STMTSTATUS_RUN 6 8618#define SQLITE_STMTSTATUS_FILTER_MISS 7 8619#define SQLITE_STMTSTATUS_FILTER_HIT 8 8620#define SQLITE_STMTSTATUS_MEMUSED 99 8621 8622/* 8623** CAPI3REF: Custom Page Cache Object 8624** 8625** The sqlite3_pcache type is opaque. It is implemented by 8626** the pluggable module. The SQLite core has no knowledge of 8627** its size or internal structure and never deals with the 8628** sqlite3_pcache object except by holding and passing pointers 8629** to the object. 8630** 8631** See [sqlite3_pcache_methods2] for additional information. 8632*/ 8633typedef struct sqlite3_pcache sqlite3_pcache; 8634 8635/* 8636** CAPI3REF: Custom Page Cache Object 8637** 8638** The sqlite3_pcache_page object represents a single page in the 8639** page cache. The page cache will allocate instances of this 8640** object. Various methods of the page cache use pointers to instances 8641** of this object as parameters or as their return value. 8642** 8643** See [sqlite3_pcache_methods2] for additional information. 8644*/ 8645typedef struct sqlite3_pcache_page sqlite3_pcache_page; 8646struct sqlite3_pcache_page { 8647 void *pBuf; /* The content of the page */ 8648 void *pExtra; /* Extra information associated with the page */ 8649}; 8650 8651/* 8652** CAPI3REF: Application Defined Page Cache. 8653** KEYWORDS: {page cache} 8654** 8655** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8656** register an alternative page cache implementation by passing in an 8657** instance of the sqlite3_pcache_methods2 structure.)^ 8658** In many applications, most of the heap memory allocated by 8659** SQLite is used for the page cache. 8660** By implementing a 8661** custom page cache using this API, an application can better control 8662** the amount of memory consumed by SQLite, the way in which 8663** that memory is allocated and released, and the policies used to 8664** determine exactly which parts of a database file are cached and for 8665** how long. 8666** 8667** The alternative page cache mechanism is an 8668** extreme measure that is only needed by the most demanding applications. 8669** The built-in page cache is recommended for most uses. 8670** 8671** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8672** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8673** the application may discard the parameter after the call to 8674** [sqlite3_config()] returns.)^ 8675** 8676** [[the xInit() page cache method]] 8677** ^(The xInit() method is called once for each effective 8678** call to [sqlite3_initialize()])^ 8679** (usually only once during the lifetime of the process). ^(The xInit() 8680** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8681** The intent of the xInit() method is to set up global data structures 8682** required by the custom page cache implementation. 8683** ^(If the xInit() method is NULL, then the 8684** built-in default page cache is used instead of the application defined 8685** page cache.)^ 8686** 8687** [[the xShutdown() page cache method]] 8688** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8689** It can be used to clean up 8690** any outstanding resources before process shutdown, if required. 8691** ^The xShutdown() method may be NULL. 8692** 8693** ^SQLite automatically serializes calls to the xInit method, 8694** so the xInit method need not be threadsafe. ^The 8695** xShutdown method is only called from [sqlite3_shutdown()] so it does 8696** not need to be threadsafe either. All other methods must be threadsafe 8697** in multithreaded applications. 8698** 8699** ^SQLite will never invoke xInit() more than once without an intervening 8700** call to xShutdown(). 8701** 8702** [[the xCreate() page cache methods]] 8703** ^SQLite invokes the xCreate() method to construct a new cache instance. 8704** SQLite will typically create one cache instance for each open database file, 8705** though this is not guaranteed. ^The 8706** first parameter, szPage, is the size in bytes of the pages that must 8707** be allocated by the cache. ^szPage will always a power of two. ^The 8708** second parameter szExtra is a number of bytes of extra storage 8709** associated with each page cache entry. ^The szExtra parameter will 8710** a number less than 250. SQLite will use the 8711** extra szExtra bytes on each page to store metadata about the underlying 8712** database page on disk. The value passed into szExtra depends 8713** on the SQLite version, the target platform, and how SQLite was compiled. 8714** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8715** created will be used to cache database pages of a file stored on disk, or 8716** false if it is used for an in-memory database. The cache implementation 8717** does not have to do anything special based with the value of bPurgeable; 8718** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 8719** never invoke xUnpin() except to deliberately delete a page. 8720** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 8721** false will always have the "discard" flag set to true. 8722** ^Hence, a cache created with bPurgeable false will 8723** never contain any unpinned pages. 8724** 8725** [[the xCachesize() page cache method]] 8726** ^(The xCachesize() method may be called at any time by SQLite to set the 8727** suggested maximum cache-size (number of pages stored by) the cache 8728** instance passed as the first argument. This is the value configured using 8729** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 8730** parameter, the implementation is not required to do anything with this 8731** value; it is advisory only. 8732** 8733** [[the xPagecount() page cache methods]] 8734** The xPagecount() method must return the number of pages currently 8735** stored in the cache, both pinned and unpinned. 8736** 8737** [[the xFetch() page cache methods]] 8738** The xFetch() method locates a page in the cache and returns a pointer to 8739** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 8740** The pBuf element of the returned sqlite3_pcache_page object will be a 8741** pointer to a buffer of szPage bytes used to store the content of a 8742** single database page. The pExtra element of sqlite3_pcache_page will be 8743** a pointer to the szExtra bytes of extra storage that SQLite has requested 8744** for each entry in the page cache. 8745** 8746** The page to be fetched is determined by the key. ^The minimum key value 8747** is 1. After it has been retrieved using xFetch, the page is considered 8748** to be "pinned". 8749** 8750** If the requested page is already in the page cache, then the page cache 8751** implementation must return a pointer to the page buffer with its content 8752** intact. If the requested page is not already in the cache, then the 8753** cache implementation should use the value of the createFlag 8754** parameter to help it determined what action to take: 8755** 8756** <table border=1 width=85% align=center> 8757** <tr><th> createFlag <th> Behavior when page is not already in cache 8758** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 8759** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 8760** Otherwise return NULL. 8761** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 8762** NULL if allocating a new page is effectively impossible. 8763** </table> 8764** 8765** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 8766** will only use a createFlag of 2 after a prior call with a createFlag of 1 8767** failed.)^ In between the xFetch() calls, SQLite may 8768** attempt to unpin one or more cache pages by spilling the content of 8769** pinned pages to disk and synching the operating system disk cache. 8770** 8771** [[the xUnpin() page cache method]] 8772** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 8773** as its second argument. If the third parameter, discard, is non-zero, 8774** then the page must be evicted from the cache. 8775** ^If the discard parameter is 8776** zero, then the page may be discarded or retained at the discretion of 8777** page cache implementation. ^The page cache implementation 8778** may choose to evict unpinned pages at any time. 8779** 8780** The cache must not perform any reference counting. A single 8781** call to xUnpin() unpins the page regardless of the number of prior calls 8782** to xFetch(). 8783** 8784** [[the xRekey() page cache methods]] 8785** The xRekey() method is used to change the key value associated with the 8786** page passed as the second argument. If the cache 8787** previously contains an entry associated with newKey, it must be 8788** discarded. ^Any prior cache entry associated with newKey is guaranteed not 8789** to be pinned. 8790** 8791** When SQLite calls the xTruncate() method, the cache must discard all 8792** existing cache entries with page numbers (keys) greater than or equal 8793** to the value of the iLimit parameter passed to xTruncate(). If any 8794** of these pages are pinned, they are implicitly unpinned, meaning that 8795** they can be safely discarded. 8796** 8797** [[the xDestroy() page cache method]] 8798** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 8799** All resources associated with the specified cache should be freed. ^After 8800** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 8801** handle invalid, and will not use it with any other sqlite3_pcache_methods2 8802** functions. 8803** 8804** [[the xShrink() page cache method]] 8805** ^SQLite invokes the xShrink() method when it wants the page cache to 8806** free up as much of heap memory as possible. The page cache implementation 8807** is not obligated to free any memory, but well-behaved implementations should 8808** do their best. 8809*/ 8810typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 8811struct sqlite3_pcache_methods2 { 8812 int iVersion; 8813 void *pArg; 8814 int (*xInit)(void*); 8815 void (*xShutdown)(void*); 8816 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 8817 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8818 int (*xPagecount)(sqlite3_pcache*); 8819 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8820 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 8821 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 8822 unsigned oldKey, unsigned newKey); 8823 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8824 void (*xDestroy)(sqlite3_pcache*); 8825 void (*xShrink)(sqlite3_pcache*); 8826}; 8827 8828/* 8829** This is the obsolete pcache_methods object that has now been replaced 8830** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 8831** retained in the header file for backwards compatibility only. 8832*/ 8833typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 8834struct sqlite3_pcache_methods { 8835 void *pArg; 8836 int (*xInit)(void*); 8837 void (*xShutdown)(void*); 8838 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 8839 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8840 int (*xPagecount)(sqlite3_pcache*); 8841 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8842 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 8843 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 8844 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8845 void (*xDestroy)(sqlite3_pcache*); 8846}; 8847 8848 8849/* 8850** CAPI3REF: Online Backup Object 8851** 8852** The sqlite3_backup object records state information about an ongoing 8853** online backup operation. ^The sqlite3_backup object is created by 8854** a call to [sqlite3_backup_init()] and is destroyed by a call to 8855** [sqlite3_backup_finish()]. 8856** 8857** See Also: [Using the SQLite Online Backup API] 8858*/ 8859typedef struct sqlite3_backup sqlite3_backup; 8860 8861/* 8862** CAPI3REF: Online Backup API. 8863** 8864** The backup API copies the content of one database into another. 8865** It is useful either for creating backups of databases or 8866** for copying in-memory databases to or from persistent files. 8867** 8868** See Also: [Using the SQLite Online Backup API] 8869** 8870** ^SQLite holds a write transaction open on the destination database file 8871** for the duration of the backup operation. 8872** ^The source database is read-locked only while it is being read; 8873** it is not locked continuously for the entire backup operation. 8874** ^Thus, the backup may be performed on a live source database without 8875** preventing other database connections from 8876** reading or writing to the source database while the backup is underway. 8877** 8878** ^(To perform a backup operation: 8879** <ol> 8880** <li><b>sqlite3_backup_init()</b> is called once to initialize the 8881** backup, 8882** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 8883** the data between the two databases, and finally 8884** <li><b>sqlite3_backup_finish()</b> is called to release all resources 8885** associated with the backup operation. 8886** </ol>)^ 8887** There should be exactly one call to sqlite3_backup_finish() for each 8888** successful call to sqlite3_backup_init(). 8889** 8890** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 8891** 8892** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 8893** [database connection] associated with the destination database 8894** and the database name, respectively. 8895** ^The database name is "main" for the main database, "temp" for the 8896** temporary database, or the name specified after the AS keyword in 8897** an [ATTACH] statement for an attached database. 8898** ^The S and M arguments passed to 8899** sqlite3_backup_init(D,N,S,M) identify the [database connection] 8900** and database name of the source database, respectively. 8901** ^The source and destination [database connections] (parameters S and D) 8902** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 8903** an error. 8904** 8905** ^A call to sqlite3_backup_init() will fail, returning NULL, if 8906** there is already a read or read-write transaction open on the 8907** destination database. 8908** 8909** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 8910** returned and an error code and error message are stored in the 8911** destination [database connection] D. 8912** ^The error code and message for the failed call to sqlite3_backup_init() 8913** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 8914** [sqlite3_errmsg16()] functions. 8915** ^A successful call to sqlite3_backup_init() returns a pointer to an 8916** [sqlite3_backup] object. 8917** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 8918** sqlite3_backup_finish() functions to perform the specified backup 8919** operation. 8920** 8921** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 8922** 8923** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 8924** the source and destination databases specified by [sqlite3_backup] object B. 8925** ^If N is negative, all remaining source pages are copied. 8926** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 8927** are still more pages to be copied, then the function returns [SQLITE_OK]. 8928** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 8929** from source to destination, then it returns [SQLITE_DONE]. 8930** ^If an error occurs while running sqlite3_backup_step(B,N), 8931** then an [error code] is returned. ^As well as [SQLITE_OK] and 8932** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 8933** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 8934** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 8935** 8936** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 8937** <ol> 8938** <li> the destination database was opened read-only, or 8939** <li> the destination database is using write-ahead-log journaling 8940** and the destination and source page sizes differ, or 8941** <li> the destination database is an in-memory database and the 8942** destination and source page sizes differ. 8943** </ol>)^ 8944** 8945** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 8946** the [sqlite3_busy_handler | busy-handler function] 8947** is invoked (if one is specified). ^If the 8948** busy-handler returns non-zero before the lock is available, then 8949** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 8950** sqlite3_backup_step() can be retried later. ^If the source 8951** [database connection] 8952** is being used to write to the source database when sqlite3_backup_step() 8953** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 8954** case the call to sqlite3_backup_step() can be retried later on. ^(If 8955** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 8956** [SQLITE_READONLY] is returned, then 8957** there is no point in retrying the call to sqlite3_backup_step(). These 8958** errors are considered fatal.)^ The application must accept 8959** that the backup operation has failed and pass the backup operation handle 8960** to the sqlite3_backup_finish() to release associated resources. 8961** 8962** ^The first call to sqlite3_backup_step() obtains an exclusive lock 8963** on the destination file. ^The exclusive lock is not released until either 8964** sqlite3_backup_finish() is called or the backup operation is complete 8965** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 8966** sqlite3_backup_step() obtains a [shared lock] on the source database that 8967** lasts for the duration of the sqlite3_backup_step() call. 8968** ^Because the source database is not locked between calls to 8969** sqlite3_backup_step(), the source database may be modified mid-way 8970** through the backup process. ^If the source database is modified by an 8971** external process or via a database connection other than the one being 8972** used by the backup operation, then the backup will be automatically 8973** restarted by the next call to sqlite3_backup_step(). ^If the source 8974** database is modified by the using the same database connection as is used 8975** by the backup operation, then the backup database is automatically 8976** updated at the same time. 8977** 8978** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 8979** 8980** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 8981** application wishes to abandon the backup operation, the application 8982** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 8983** ^The sqlite3_backup_finish() interfaces releases all 8984** resources associated with the [sqlite3_backup] object. 8985** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 8986** active write-transaction on the destination database is rolled back. 8987** The [sqlite3_backup] object is invalid 8988** and may not be used following a call to sqlite3_backup_finish(). 8989** 8990** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 8991** sqlite3_backup_step() errors occurred, regardless or whether or not 8992** sqlite3_backup_step() completed. 8993** ^If an out-of-memory condition or IO error occurred during any prior 8994** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 8995** sqlite3_backup_finish() returns the corresponding [error code]. 8996** 8997** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 8998** is not a permanent error and does not affect the return value of 8999** sqlite3_backup_finish(). 9000** 9001** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 9002** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 9003** 9004** ^The sqlite3_backup_remaining() routine returns the number of pages still 9005** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 9006** ^The sqlite3_backup_pagecount() routine returns the total number of pages 9007** in the source database at the conclusion of the most recent 9008** sqlite3_backup_step(). 9009** ^(The values returned by these functions are only updated by 9010** sqlite3_backup_step(). If the source database is modified in a way that 9011** changes the size of the source database or the number of pages remaining, 9012** those changes are not reflected in the output of sqlite3_backup_pagecount() 9013** and sqlite3_backup_remaining() until after the next 9014** sqlite3_backup_step().)^ 9015** 9016** <b>Concurrent Usage of Database Handles</b> 9017** 9018** ^The source [database connection] may be used by the application for other 9019** purposes while a backup operation is underway or being initialized. 9020** ^If SQLite is compiled and configured to support threadsafe database 9021** connections, then the source database connection may be used concurrently 9022** from within other threads. 9023** 9024** However, the application must guarantee that the destination 9025** [database connection] is not passed to any other API (by any thread) after 9026** sqlite3_backup_init() is called and before the corresponding call to 9027** sqlite3_backup_finish(). SQLite does not currently check to see 9028** if the application incorrectly accesses the destination [database connection] 9029** and so no error code is reported, but the operations may malfunction 9030** nevertheless. Use of the destination database connection while a 9031** backup is in progress might also cause a mutex deadlock. 9032** 9033** If running in [shared cache mode], the application must 9034** guarantee that the shared cache used by the destination database 9035** is not accessed while the backup is running. In practice this means 9036** that the application must guarantee that the disk file being 9037** backed up to is not accessed by any connection within the process, 9038** not just the specific connection that was passed to sqlite3_backup_init(). 9039** 9040** The [sqlite3_backup] object itself is partially threadsafe. Multiple 9041** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 9042** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 9043** APIs are not strictly speaking threadsafe. If they are invoked at the 9044** same time as another thread is invoking sqlite3_backup_step() it is 9045** possible that they return invalid values. 9046*/ 9047sqlite3_backup *sqlite3_backup_init( 9048 sqlite3 *pDest, /* Destination database handle */ 9049 const char *zDestName, /* Destination database name */ 9050 sqlite3 *pSource, /* Source database handle */ 9051 const char *zSourceName /* Source database name */ 9052); 9053int sqlite3_backup_step(sqlite3_backup *p, int nPage); 9054int sqlite3_backup_finish(sqlite3_backup *p); 9055int sqlite3_backup_remaining(sqlite3_backup *p); 9056int sqlite3_backup_pagecount(sqlite3_backup *p); 9057 9058/* 9059** CAPI3REF: Unlock Notification 9060** METHOD: sqlite3 9061** 9062** ^When running in shared-cache mode, a database operation may fail with 9063** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 9064** individual tables within the shared-cache cannot be obtained. See 9065** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 9066** ^This API may be used to register a callback that SQLite will invoke 9067** when the connection currently holding the required lock relinquishes it. 9068** ^This API is only available if the library was compiled with the 9069** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 9070** 9071** See Also: [Using the SQLite Unlock Notification Feature]. 9072** 9073** ^Shared-cache locks are released when a database connection concludes 9074** its current transaction, either by committing it or rolling it back. 9075** 9076** ^When a connection (known as the blocked connection) fails to obtain a 9077** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 9078** identity of the database connection (the blocking connection) that 9079** has locked the required resource is stored internally. ^After an 9080** application receives an SQLITE_LOCKED error, it may call the 9081** sqlite3_unlock_notify() method with the blocked connection handle as 9082** the first argument to register for a callback that will be invoked 9083** when the blocking connections current transaction is concluded. ^The 9084** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 9085** call that concludes the blocking connection's transaction. 9086** 9087** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 9088** there is a chance that the blocking connection will have already 9089** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 9090** If this happens, then the specified callback is invoked immediately, 9091** from within the call to sqlite3_unlock_notify().)^ 9092** 9093** ^If the blocked connection is attempting to obtain a write-lock on a 9094** shared-cache table, and more than one other connection currently holds 9095** a read-lock on the same table, then SQLite arbitrarily selects one of 9096** the other connections to use as the blocking connection. 9097** 9098** ^(There may be at most one unlock-notify callback registered by a 9099** blocked connection. If sqlite3_unlock_notify() is called when the 9100** blocked connection already has a registered unlock-notify callback, 9101** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 9102** called with a NULL pointer as its second argument, then any existing 9103** unlock-notify callback is canceled. ^The blocked connections 9104** unlock-notify callback may also be canceled by closing the blocked 9105** connection using [sqlite3_close()]. 9106** 9107** The unlock-notify callback is not reentrant. If an application invokes 9108** any sqlite3_xxx API functions from within an unlock-notify callback, a 9109** crash or deadlock may be the result. 9110** 9111** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 9112** returns SQLITE_OK. 9113** 9114** <b>Callback Invocation Details</b> 9115** 9116** When an unlock-notify callback is registered, the application provides a 9117** single void* pointer that is passed to the callback when it is invoked. 9118** However, the signature of the callback function allows SQLite to pass 9119** it an array of void* context pointers. The first argument passed to 9120** an unlock-notify callback is a pointer to an array of void* pointers, 9121** and the second is the number of entries in the array. 9122** 9123** When a blocking connection's transaction is concluded, there may be 9124** more than one blocked connection that has registered for an unlock-notify 9125** callback. ^If two or more such blocked connections have specified the 9126** same callback function, then instead of invoking the callback function 9127** multiple times, it is invoked once with the set of void* context pointers 9128** specified by the blocked connections bundled together into an array. 9129** This gives the application an opportunity to prioritize any actions 9130** related to the set of unblocked database connections. 9131** 9132** <b>Deadlock Detection</b> 9133** 9134** Assuming that after registering for an unlock-notify callback a 9135** database waits for the callback to be issued before taking any further 9136** action (a reasonable assumption), then using this API may cause the 9137** application to deadlock. For example, if connection X is waiting for 9138** connection Y's transaction to be concluded, and similarly connection 9139** Y is waiting on connection X's transaction, then neither connection 9140** will proceed and the system may remain deadlocked indefinitely. 9141** 9142** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 9143** detection. ^If a given call to sqlite3_unlock_notify() would put the 9144** system in a deadlocked state, then SQLITE_LOCKED is returned and no 9145** unlock-notify callback is registered. The system is said to be in 9146** a deadlocked state if connection A has registered for an unlock-notify 9147** callback on the conclusion of connection B's transaction, and connection 9148** B has itself registered for an unlock-notify callback when connection 9149** A's transaction is concluded. ^Indirect deadlock is also detected, so 9150** the system is also considered to be deadlocked if connection B has 9151** registered for an unlock-notify callback on the conclusion of connection 9152** C's transaction, where connection C is waiting on connection A. ^Any 9153** number of levels of indirection are allowed. 9154** 9155** <b>The "DROP TABLE" Exception</b> 9156** 9157** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 9158** always appropriate to call sqlite3_unlock_notify(). There is however, 9159** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 9160** SQLite checks if there are any currently executing SELECT statements 9161** that belong to the same connection. If there are, SQLITE_LOCKED is 9162** returned. In this case there is no "blocking connection", so invoking 9163** sqlite3_unlock_notify() results in the unlock-notify callback being 9164** invoked immediately. If the application then re-attempts the "DROP TABLE" 9165** or "DROP INDEX" query, an infinite loop might be the result. 9166** 9167** One way around this problem is to check the extended error code returned 9168** by an sqlite3_step() call. ^(If there is a blocking connection, then the 9169** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 9170** the special "DROP TABLE/INDEX" case, the extended error code is just 9171** SQLITE_LOCKED.)^ 9172*/ 9173int sqlite3_unlock_notify( 9174 sqlite3 *pBlocked, /* Waiting connection */ 9175 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 9176 void *pNotifyArg /* Argument to pass to xNotify */ 9177); 9178 9179 9180/* 9181** CAPI3REF: String Comparison 9182** 9183** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 9184** and extensions to compare the contents of two buffers containing UTF-8 9185** strings in a case-independent fashion, using the same definition of "case 9186** independence" that SQLite uses internally when comparing identifiers. 9187*/ 9188int sqlite3_stricmp(const char *, const char *); 9189int sqlite3_strnicmp(const char *, const char *, int); 9190 9191/* 9192** CAPI3REF: String Globbing 9193* 9194** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 9195** string X matches the [GLOB] pattern P. 9196** ^The definition of [GLOB] pattern matching used in 9197** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 9198** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 9199** is case sensitive. 9200** 9201** Note that this routine returns zero on a match and non-zero if the strings 9202** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9203** 9204** See also: [sqlite3_strlike()]. 9205*/ 9206int sqlite3_strglob(const char *zGlob, const char *zStr); 9207 9208/* 9209** CAPI3REF: String LIKE Matching 9210* 9211** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 9212** string X matches the [LIKE] pattern P with escape character E. 9213** ^The definition of [LIKE] pattern matching used in 9214** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 9215** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 9216** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 9217** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 9218** insensitive - equivalent upper and lower case ASCII characters match 9219** one another. 9220** 9221** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 9222** only ASCII characters are case folded. 9223** 9224** Note that this routine returns zero on a match and non-zero if the strings 9225** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9226** 9227** See also: [sqlite3_strglob()]. 9228*/ 9229int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 9230 9231/* 9232** CAPI3REF: Error Logging Interface 9233** 9234** ^The [sqlite3_log()] interface writes a message into the [error log] 9235** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 9236** ^If logging is enabled, the zFormat string and subsequent arguments are 9237** used with [sqlite3_snprintf()] to generate the final output string. 9238** 9239** The sqlite3_log() interface is intended for use by extensions such as 9240** virtual tables, collating functions, and SQL functions. While there is 9241** nothing to prevent an application from calling sqlite3_log(), doing so 9242** is considered bad form. 9243** 9244** The zFormat string must not be NULL. 9245** 9246** To avoid deadlocks and other threading problems, the sqlite3_log() routine 9247** will not use dynamically allocated memory. The log message is stored in 9248** a fixed-length buffer on the stack. If the log message is longer than 9249** a few hundred characters, it will be truncated to the length of the 9250** buffer. 9251*/ 9252void sqlite3_log(int iErrCode, const char *zFormat, ...); 9253 9254/* 9255** CAPI3REF: Write-Ahead Log Commit Hook 9256** METHOD: sqlite3 9257** 9258** ^The [sqlite3_wal_hook()] function is used to register a callback that 9259** is invoked each time data is committed to a database in wal mode. 9260** 9261** ^(The callback is invoked by SQLite after the commit has taken place and 9262** the associated write-lock on the database released)^, so the implementation 9263** may read, write or [checkpoint] the database as required. 9264** 9265** ^The first parameter passed to the callback function when it is invoked 9266** is a copy of the third parameter passed to sqlite3_wal_hook() when 9267** registering the callback. ^The second is a copy of the database handle. 9268** ^The third parameter is the name of the database that was written to - 9269** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 9270** is the number of pages currently in the write-ahead log file, 9271** including those that were just committed. 9272** 9273** The callback function should normally return [SQLITE_OK]. ^If an error 9274** code is returned, that error will propagate back up through the 9275** SQLite code base to cause the statement that provoked the callback 9276** to report an error, though the commit will have still occurred. If the 9277** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 9278** that does not correspond to any valid SQLite error code, the results 9279** are undefined. 9280** 9281** A single database handle may have at most a single write-ahead log callback 9282** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 9283** previously registered write-ahead log callback. ^The return value is 9284** a copy of the third parameter from the previous call, if any, or 0. 9285** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the 9286** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 9287** overwrite any prior [sqlite3_wal_hook()] settings. 9288*/ 9289void *sqlite3_wal_hook( 9290 sqlite3*, 9291 int(*)(void *,sqlite3*,const char*,int), 9292 void* 9293); 9294 9295/* 9296** CAPI3REF: Configure an auto-checkpoint 9297** METHOD: sqlite3 9298** 9299** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 9300** [sqlite3_wal_hook()] that causes any database on [database connection] D 9301** to automatically [checkpoint] 9302** after committing a transaction if there are N or 9303** more frames in the [write-ahead log] file. ^Passing zero or 9304** a negative value as the nFrame parameter disables automatic 9305** checkpoints entirely. 9306** 9307** ^The callback registered by this function replaces any existing callback 9308** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 9309** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 9310** configured by this function. 9311** 9312** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 9313** from SQL. 9314** 9315** ^Checkpoints initiated by this mechanism are 9316** [sqlite3_wal_checkpoint_v2|PASSIVE]. 9317** 9318** ^Every new [database connection] defaults to having the auto-checkpoint 9319** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 9320** pages. The use of this interface 9321** is only necessary if the default setting is found to be suboptimal 9322** for a particular application. 9323*/ 9324int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 9325 9326/* 9327** CAPI3REF: Checkpoint a database 9328** METHOD: sqlite3 9329** 9330** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 9331** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 9332** 9333** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 9334** [write-ahead log] for database X on [database connection] D to be 9335** transferred into the database file and for the write-ahead log to 9336** be reset. See the [checkpointing] documentation for addition 9337** information. 9338** 9339** This interface used to be the only way to cause a checkpoint to 9340** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 9341** interface was added. This interface is retained for backwards 9342** compatibility and as a convenience for applications that need to manually 9343** start a callback but which do not need the full power (and corresponding 9344** complication) of [sqlite3_wal_checkpoint_v2()]. 9345*/ 9346int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 9347 9348/* 9349** CAPI3REF: Checkpoint a database 9350** METHOD: sqlite3 9351** 9352** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 9353** operation on database X of [database connection] D in mode M. Status 9354** information is written back into integers pointed to by L and C.)^ 9355** ^(The M parameter must be a valid [checkpoint mode]:)^ 9356** 9357** <dl> 9358** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 9359** ^Checkpoint as many frames as possible without waiting for any database 9360** readers or writers to finish, then sync the database file if all frames 9361** in the log were checkpointed. ^The [busy-handler callback] 9362** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 9363** ^On the other hand, passive mode might leave the checkpoint unfinished 9364** if there are concurrent readers or writers. 9365** 9366** <dt>SQLITE_CHECKPOINT_FULL<dd> 9367** ^This mode blocks (it invokes the 9368** [sqlite3_busy_handler|busy-handler callback]) until there is no 9369** database writer and all readers are reading from the most recent database 9370** snapshot. ^It then checkpoints all frames in the log file and syncs the 9371** database file. ^This mode blocks new database writers while it is pending, 9372** but new database readers are allowed to continue unimpeded. 9373** 9374** <dt>SQLITE_CHECKPOINT_RESTART<dd> 9375** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 9376** that after checkpointing the log file it blocks (calls the 9377** [busy-handler callback]) 9378** until all readers are reading from the database file only. ^This ensures 9379** that the next writer will restart the log file from the beginning. 9380** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 9381** database writer attempts while it is pending, but does not impede readers. 9382** 9383** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 9384** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 9385** addition that it also truncates the log file to zero bytes just prior 9386** to a successful return. 9387** </dl> 9388** 9389** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 9390** the log file or to -1 if the checkpoint could not run because 9391** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 9392** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 9393** log file (including any that were already checkpointed before the function 9394** was called) or to -1 if the checkpoint could not run due to an error or 9395** because the database is not in WAL mode. ^Note that upon successful 9396** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 9397** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 9398** 9399** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 9400** any other process is running a checkpoint operation at the same time, the 9401** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 9402** busy-handler configured, it will not be invoked in this case. 9403** 9404** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 9405** exclusive "writer" lock on the database file. ^If the writer lock cannot be 9406** obtained immediately, and a busy-handler is configured, it is invoked and 9407** the writer lock retried until either the busy-handler returns 0 or the lock 9408** is successfully obtained. ^The busy-handler is also invoked while waiting for 9409** database readers as described above. ^If the busy-handler returns 0 before 9410** the writer lock is obtained or while waiting for database readers, the 9411** checkpoint operation proceeds from that point in the same way as 9412** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 9413** without blocking any further. ^SQLITE_BUSY is returned in this case. 9414** 9415** ^If parameter zDb is NULL or points to a zero length string, then the 9416** specified operation is attempted on all WAL databases [attached] to 9417** [database connection] db. In this case the 9418** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 9419** an SQLITE_BUSY error is encountered when processing one or more of the 9420** attached WAL databases, the operation is still attempted on any remaining 9421** attached databases and SQLITE_BUSY is returned at the end. ^If any other 9422** error occurs while processing an attached database, processing is abandoned 9423** and the error code is returned to the caller immediately. ^If no error 9424** (SQLITE_BUSY or otherwise) is encountered while processing the attached 9425** databases, SQLITE_OK is returned. 9426** 9427** ^If database zDb is the name of an attached database that is not in WAL 9428** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 9429** zDb is not NULL (or a zero length string) and is not the name of any 9430** attached database, SQLITE_ERROR is returned to the caller. 9431** 9432** ^Unless it returns SQLITE_MISUSE, 9433** the sqlite3_wal_checkpoint_v2() interface 9434** sets the error information that is queried by 9435** [sqlite3_errcode()] and [sqlite3_errmsg()]. 9436** 9437** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 9438** from SQL. 9439*/ 9440int sqlite3_wal_checkpoint_v2( 9441 sqlite3 *db, /* Database handle */ 9442 const char *zDb, /* Name of attached database (or NULL) */ 9443 int eMode, /* SQLITE_CHECKPOINT_* value */ 9444 int *pnLog, /* OUT: Size of WAL log in frames */ 9445 int *pnCkpt /* OUT: Total number of frames checkpointed */ 9446); 9447 9448/* 9449** CAPI3REF: Checkpoint Mode Values 9450** KEYWORDS: {checkpoint mode} 9451** 9452** These constants define all valid values for the "checkpoint mode" passed 9453** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 9454** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 9455** meaning of each of these checkpoint modes. 9456*/ 9457#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9458#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9459#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ 9460#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9461 9462/* 9463** CAPI3REF: Virtual Table Interface Configuration 9464** 9465** This function may be called by either the [xConnect] or [xCreate] method 9466** of a [virtual table] implementation to configure 9467** various facets of the virtual table interface. 9468** 9469** If this interface is invoked outside the context of an xConnect or 9470** xCreate virtual table method then the behavior is undefined. 9471** 9472** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9473** [database connection] in which the virtual table is being created and 9474** which is passed in as the first argument to the [xConnect] or [xCreate] 9475** method that is invoking sqlite3_vtab_config(). The C parameter is one 9476** of the [virtual table configuration options]. The presence and meaning 9477** of parameters after C depend on which [virtual table configuration option] 9478** is used. 9479*/ 9480int sqlite3_vtab_config(sqlite3*, int op, ...); 9481 9482/* 9483** CAPI3REF: Virtual Table Configuration Options 9484** KEYWORDS: {virtual table configuration options} 9485** KEYWORDS: {virtual table configuration option} 9486** 9487** These macros define the various options to the 9488** [sqlite3_vtab_config()] interface that [virtual table] implementations 9489** can use to customize and optimize their behavior. 9490** 9491** <dl> 9492** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9493** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9494** <dd>Calls of the form 9495** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9496** where X is an integer. If X is zero, then the [virtual table] whose 9497** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9498** support constraints. In this configuration (which is the default) if 9499** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9500** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9501** specified as part of the users SQL statement, regardless of the actual 9502** ON CONFLICT mode specified. 9503** 9504** If X is non-zero, then the virtual table implementation guarantees 9505** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9506** any modifications to internal or persistent data structures have been made. 9507** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9508** is able to roll back a statement or database transaction, and abandon 9509** or continue processing the current SQL statement as appropriate. 9510** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9511** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9512** had been ABORT. 9513** 9514** Virtual table implementations that are required to handle OR REPLACE 9515** must do so within the [xUpdate] method. If a call to the 9516** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9517** CONFLICT policy is REPLACE, the virtual table implementation should 9518** silently replace the appropriate rows within the xUpdate callback and 9519** return SQLITE_OK. Or, if this is not possible, it may return 9520** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9521** constraint handling. 9522** </dd> 9523** 9524** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9525** <dd>Calls of the form 9526** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9527** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9528** prohibits that virtual table from being used from within triggers and 9529** views. 9530** </dd> 9531** 9532** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9533** <dd>Calls of the form 9534** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9535** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9536** identify that virtual table as being safe to use from within triggers 9537** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9538** virtual table can do no serious harm even if it is controlled by a 9539** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9540** flag unless absolutely necessary. 9541** </dd> 9542** </dl> 9543*/ 9544#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9545#define SQLITE_VTAB_INNOCUOUS 2 9546#define SQLITE_VTAB_DIRECTONLY 3 9547 9548/* 9549** CAPI3REF: Determine The Virtual Table Conflict Policy 9550** 9551** This function may only be called from within a call to the [xUpdate] method 9552** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9553** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9554** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9555** of the SQL statement that triggered the call to the [xUpdate] method of the 9556** [virtual table]. 9557*/ 9558int sqlite3_vtab_on_conflict(sqlite3 *); 9559 9560/* 9561** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9562** 9563** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9564** method of a [virtual table], then it might return true if the 9565** column is being fetched as part of an UPDATE operation during which the 9566** column value will not change. The virtual table implementation can use 9567** this hint as permission to substitute a return value that is less 9568** expensive to compute and that the corresponding 9569** [xUpdate] method understands as a "no-change" value. 9570** 9571** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9572** the column is not changed by the UPDATE statement, then the xColumn 9573** method can optionally return without setting a result, without calling 9574** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9575** In that case, [sqlite3_value_nochange(X)] will return true for the 9576** same column in the [xUpdate] method. 9577** 9578** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 9579** implementations should continue to give a correct answer even if the 9580** sqlite3_vtab_nochange() interface were to always return false. In the 9581** current implementation, the sqlite3_vtab_nochange() interface does always 9582** returns false for the enhanced [UPDATE FROM] statement. 9583*/ 9584int sqlite3_vtab_nochange(sqlite3_context*); 9585 9586/* 9587** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9588** METHOD: sqlite3_index_info 9589** 9590** This function may only be called from within a call to the [xBestIndex] 9591** method of a [virtual table]. This function returns a pointer to a string 9592** that is the name of the appropriate collation sequence to use for text 9593** comparisons on the constraint identified by its arguments. 9594** 9595** The first argument must be the pointer to the [sqlite3_index_info] object 9596** that is the first parameter to the xBestIndex() method. The second argument 9597** must be an index into the aConstraint[] array belonging to the 9598** sqlite3_index_info structure passed to xBestIndex. 9599** 9600** Important: 9601** The first parameter must be the same pointer that is passed into the 9602** xBestMethod() method. The first parameter may not be a pointer to a 9603** different [sqlite3_index_info] object, even an exact copy. 9604** 9605** The return value is computed as follows: 9606** 9607** <ol> 9608** <li><p> If the constraint comes from a WHERE clause expression that contains 9609** a [COLLATE operator], then the name of the collation specified by 9610** that COLLATE operator is returned. 9611** <li><p> If there is no COLLATE operator, but the column that is the subject 9612** of the constraint specifies an alternative collating sequence via 9613** a [COLLATE clause] on the column definition within the CREATE TABLE 9614** statement that was passed into [sqlite3_declare_vtab()], then the 9615** name of that alternative collating sequence is returned. 9616** <li><p> Otherwise, "BINARY" is returned. 9617** </ol> 9618*/ 9619SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9620 9621/* 9622** CAPI3REF: Determine if a virtual table query is DISTINCT 9623** METHOD: sqlite3_index_info 9624** 9625** This API may only be used from within an [xBestIndex|xBestIndex method] 9626** of a [virtual table] implementation. The result of calling this 9627** interface from outside of xBestIndex() is undefined and probably harmful. 9628** 9629** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and 9630** 3. The integer returned by sqlite3_vtab_distinct() 9631** gives the virtual table additional information about how the query 9632** planner wants the output to be ordered. As long as the virtual table 9633** can meet the ordering requirements of the query planner, it may set 9634** the "orderByConsumed" flag. 9635** 9636** <ol><li value="0"><p> 9637** ^If the sqlite3_vtab_distinct() interface returns 0, that means 9638** that the query planner needs the virtual table to return all rows in the 9639** sort order defined by the "nOrderBy" and "aOrderBy" fields of the 9640** [sqlite3_index_info] object. This is the default expectation. If the 9641** virtual table outputs all rows in sorted order, then it is always safe for 9642** the xBestIndex method to set the "orderByConsumed" flag, regardless of 9643** the return value from sqlite3_vtab_distinct(). 9644** <li value="1"><p> 9645** ^(If the sqlite3_vtab_distinct() interface returns 1, that means 9646** that the query planner does not need the rows to be returned in sorted order 9647** as long as all rows with the same values in all columns identified by the 9648** "aOrderBy" field are adjacent.)^ This mode is used when the query planner 9649** is doing a GROUP BY. 9650** <li value="2"><p> 9651** ^(If the sqlite3_vtab_distinct() interface returns 2, that means 9652** that the query planner does not need the rows returned in any particular 9653** order, as long as rows with the same values in all "aOrderBy" columns 9654** are adjacent.)^ ^(Furthermore, only a single row for each particular 9655** combination of values in the columns identified by the "aOrderBy" field 9656** needs to be returned.)^ ^It is always ok for two or more rows with the same 9657** values in all "aOrderBy" columns to be returned, as long as all such rows 9658** are adjacent. ^The virtual table may, if it chooses, omit extra rows 9659** that have the same value for all columns identified by "aOrderBy". 9660** ^However omitting the extra rows is optional. 9661** This mode is used for a DISTINCT query. 9662** <li value="3"><p> 9663** ^(If the sqlite3_vtab_distinct() interface returns 3, that means 9664** that the query planner needs only distinct rows but it does need the 9665** rows to be sorted.)^ ^The virtual table implementation is free to omit 9666** rows that are identical in all aOrderBy columns, if it wants to, but 9667** it is not required to omit any rows. This mode is used for queries 9668** that have both DISTINCT and ORDER BY clauses. 9669** </ol> 9670** 9671** ^For the purposes of comparing virtual table output values to see if the 9672** values are same value for sorting purposes, two NULL values are considered 9673** to be the same. In other words, the comparison operator is "IS" 9674** (or "IS NOT DISTINCT FROM") and not "==". 9675** 9676** If a virtual table implementation is unable to meet the requirements 9677** specified above, then it must not set the "orderByConsumed" flag in the 9678** [sqlite3_index_info] object or an incorrect answer may result. 9679** 9680** ^A virtual table implementation is always free to return rows in any order 9681** it wants, as long as the "orderByConsumed" flag is not set. ^When the 9682** the "orderByConsumed" flag is unset, the query planner will add extra 9683** [bytecode] to ensure that the final results returned by the SQL query are 9684** ordered correctly. The use of the "orderByConsumed" flag and the 9685** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful 9686** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" 9687** flag might help queries against a virtual table to run faster. Being 9688** overly aggressive and setting the "orderByConsumed" flag when it is not 9689** valid to do so, on the other hand, might cause SQLite to return incorrect 9690** results. 9691*/ 9692int sqlite3_vtab_distinct(sqlite3_index_info*); 9693 9694/* 9695** CAPI3REF: Identify and handle IN constraints in xBestIndex 9696** 9697** This interface may only be used from within an 9698** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. 9699** The result of invoking this interface from any other context is 9700** undefined and probably harmful. 9701** 9702** ^(A constraint on a virtual table of the form 9703** "[IN operator|column IN (...)]" is 9704** communicated to the xBestIndex method as a 9705** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use 9706** this constraint, it must set the corresponding 9707** aConstraintUsage[].argvIndex to a postive integer. ^(Then, under 9708** the usual mode of handling IN operators, SQLite generates [bytecode] 9709** that invokes the [xFilter|xFilter() method] once for each value 9710** on the right-hand side of the IN operator.)^ Thus the virtual table 9711** only sees a single value from the right-hand side of the IN operator 9712** at a time. 9713** 9714** In some cases, however, it would be advantageous for the virtual 9715** table to see all values on the right-hand of the IN operator all at 9716** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: 9717** 9718** <ol> 9719** <li><p> 9720** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) 9721** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint 9722** is an [IN operator] that can be processed all at once. ^In other words, 9723** sqlite3_vtab_in() with -1 in the third argument is a mechanism 9724** by which the virtual table can ask SQLite if all-at-once processing 9725** of the IN operator is even possible. 9726** 9727** <li><p> 9728** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates 9729** to SQLite that the virtual table does or does not want to process 9730** the IN operator all-at-once, respectively. ^Thus when the third 9731** parameter (F) is non-negative, this interface is the mechanism by 9732** which the virtual table tells SQLite how it wants to process the 9733** IN operator. 9734** </ol> 9735** 9736** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times 9737** within the same xBestIndex method call. ^For any given P,N pair, 9738** the return value from sqlite3_vtab_in(P,N,F) will always be the same 9739** within the same xBestIndex call. ^If the interface returns true 9740** (non-zero), that means that the constraint is an IN operator 9741** that can be processed all-at-once. ^If the constraint is not an IN 9742** operator or cannot be processed all-at-once, then the interface returns 9743** false. 9744** 9745** ^(All-at-once processing of the IN operator is selected if both of the 9746** following conditions are met: 9747** 9748** <ol> 9749** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive 9750** integer. This is how the virtual table tells SQLite that it wants to 9751** use the N-th constraint. 9752** 9753** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was 9754** non-negative had F>=1. 9755** </ol>)^ 9756** 9757** ^If either or both of the conditions above are false, then SQLite uses 9758** the traditional one-at-a-time processing strategy for the IN constraint. 9759** ^If both conditions are true, then the argvIndex-th parameter to the 9760** xFilter method will be an [sqlite3_value] that appears to be NULL, 9761** but which can be passed to [sqlite3_vtab_in_first()] and 9762** [sqlite3_vtab_in_next()] to find all values on the right-hand side 9763** of the IN constraint. 9764*/ 9765int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); 9766 9767/* 9768** CAPI3REF: Find all elements on the right-hand side of an IN constraint. 9769** 9770** These interfaces are only useful from within the 9771** [xFilter|xFilter() method] of a [virtual table] implementation. 9772** The result of invoking these interfaces from any other context 9773** is undefined and probably harmful. 9774** 9775** The X parameter in a call to sqlite3_vtab_in_first(X,P) or 9776** sqlite3_vtab_in_next(X,P) must be one of the parameters to the 9777** xFilter method which invokes these routines, and specifically 9778** a parameter that was previously selected for all-at-once IN constraint 9779** processing use the [sqlite3_vtab_in()] interface in the 9780** [xBestIndex|xBestIndex method]. ^(If the X parameter is not 9781** an xFilter argument that was selected for all-at-once IN constraint 9782** processing, then these routines return [SQLITE_MISUSE])^ or perhaps 9783** exhibit some other undefined or harmful behavior. 9784** 9785** ^(Use these routines to access all values on the right-hand side 9786** of the IN constraint using code like the following: 9787** 9788** <blockquote><pre> 9789** for(rc=sqlite3_vtab_in_first(pList, &pVal); 9790** rc==SQLITE_OK && pVal 9791** rc=sqlite3_vtab_in_next(pList, &pVal) 9792** ){ 9793** // do something with pVal 9794** } 9795** if( rc!=SQLITE_OK ){ 9796** // an error has occurred 9797** } 9798** </pre></blockquote>)^ 9799** 9800** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) 9801** routines return SQLITE_OK and set *P to point to the first or next value 9802** on the RHS of the IN constraint. ^If there are no more values on the 9803** right hand side of the IN constraint, then *P is set to NULL and these 9804** routines return [SQLITE_DONE]. ^The return value might be 9805** some other value, such as SQLITE_NOMEM, in the event of a malfunction. 9806** 9807** The *ppOut values returned by these routines are only valid until the 9808** next call to either of these routines or until the end of the xFilter 9809** method from which these routines were called. If the virtual table 9810** implementation needs to retain the *ppOut values for longer, it must make 9811** copies. The *ppOut values are [protected sqlite3_value|protected]. 9812*/ 9813int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); 9814int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); 9815 9816/* 9817** CAPI3REF: Constraint values in xBestIndex() 9818** METHOD: sqlite3_index_info 9819** 9820** This API may only be used from within the [xBestIndex|xBestIndex method] 9821** of a [virtual table] implementation. The result of calling this interface 9822** from outside of an xBestIndex method are undefined and probably harmful. 9823** 9824** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within 9825** the [xBestIndex] method of a [virtual table] implementation, with P being 9826** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and 9827** J being a 0-based index into P->aConstraint[], then this routine 9828** attempts to set *V to the value of the right-hand operand of 9829** that constraint if the right-hand operand is known. ^If the 9830** right-hand operand is not known, then *V is set to a NULL pointer. 9831** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if 9832** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) 9833** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th 9834** constraint is not available. ^The sqlite3_vtab_rhs_value() interface 9835** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if 9836** something goes wrong. 9837** 9838** The sqlite3_vtab_rhs_value() interface is usually only successful if 9839** the right-hand operand of a constraint is a literal value in the original 9840** SQL statement. If the right-hand operand is an expression or a reference 9841** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() 9842** will probably return [SQLITE_NOTFOUND]. 9843** 9844** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and 9845** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such 9846** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ 9847** 9848** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value 9849** and remains valid for the duration of the xBestIndex method call. 9850** ^When xBestIndex returns, the sqlite3_value object returned by 9851** sqlite3_vtab_rhs_value() is automatically deallocated. 9852** 9853** The "_rhs_" in the name of this routine is an abbreviation for 9854** "Right-Hand Side". 9855*/ 9856int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); 9857 9858/* 9859** CAPI3REF: Conflict resolution modes 9860** KEYWORDS: {conflict resolution mode} 9861** 9862** These constants are returned by [sqlite3_vtab_on_conflict()] to 9863** inform a [virtual table] implementation what the [ON CONFLICT] mode 9864** is for the SQL statement being evaluated. 9865** 9866** Note that the [SQLITE_IGNORE] constant is also used as a potential 9867** return value from the [sqlite3_set_authorizer()] callback and that 9868** [SQLITE_ABORT] is also a [result code]. 9869*/ 9870#define SQLITE_ROLLBACK 1 9871/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 9872#define SQLITE_FAIL 3 9873/* #define SQLITE_ABORT 4 // Also an error code */ 9874#define SQLITE_REPLACE 5 9875 9876/* 9877** CAPI3REF: Prepared Statement Scan Status Opcodes 9878** KEYWORDS: {scanstatus options} 9879** 9880** The following constants can be used for the T parameter to the 9881** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 9882** different metric for sqlite3_stmt_scanstatus() to return. 9883** 9884** When the value returned to V is a string, space to hold that string is 9885** managed by the prepared statement S and will be automatically freed when 9886** S is finalized. 9887** 9888** <dl> 9889** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 9890** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 9891** set to the total number of times that the X-th loop has run.</dd> 9892** 9893** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 9894** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 9895** to the total number of rows examined by all iterations of the X-th loop.</dd> 9896** 9897** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 9898** <dd>^The "double" variable pointed to by the V parameter will be set to the 9899** query planner's estimate for the average number of rows output from each 9900** iteration of the X-th loop. If the query planner's estimates was accurate, 9901** then this value will approximate the quotient NVISIT/NLOOP and the 9902** product of this value for all prior loops with the same SELECTID will 9903** be the NLOOP value for the current loop. 9904** 9905** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 9906** <dd>^The "const char *" variable pointed to by the V parameter will be set 9907** to a zero-terminated UTF-8 string containing the name of the index or table 9908** used for the X-th loop. 9909** 9910** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 9911** <dd>^The "const char *" variable pointed to by the V parameter will be set 9912** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 9913** description for the X-th loop. 9914** 9915** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 9916** <dd>^The "int" variable pointed to by the V parameter will be set to the 9917** "select-id" for the X-th loop. The select-id identifies which query or 9918** subquery the loop is part of. The main query has a select-id of zero. 9919** The select-id is the same value as is output in the first column 9920** of an [EXPLAIN QUERY PLAN] query. 9921** </dl> 9922*/ 9923#define SQLITE_SCANSTAT_NLOOP 0 9924#define SQLITE_SCANSTAT_NVISIT 1 9925#define SQLITE_SCANSTAT_EST 2 9926#define SQLITE_SCANSTAT_NAME 3 9927#define SQLITE_SCANSTAT_EXPLAIN 4 9928#define SQLITE_SCANSTAT_SELECTID 5 9929 9930/* 9931** CAPI3REF: Prepared Statement Scan Status 9932** METHOD: sqlite3_stmt 9933** 9934** This interface returns information about the predicted and measured 9935** performance for pStmt. Advanced applications can use this 9936** interface to compare the predicted and the measured performance and 9937** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 9938** 9939** Since this interface is expected to be rarely used, it is only 9940** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 9941** compile-time option. 9942** 9943** The "iScanStatusOp" parameter determines which status information to return. 9944** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 9945** of this interface is undefined. 9946** ^The requested measurement is written into a variable pointed to by 9947** the "pOut" parameter. 9948** Parameter "idx" identifies the specific loop to retrieve statistics for. 9949** Loops are numbered starting from zero. ^If idx is out of range - less than 9950** zero or greater than or equal to the total number of loops used to implement 9951** the statement - a non-zero value is returned and the variable that pOut 9952** points to is unchanged. 9953** 9954** ^Statistics might not be available for all loops in all statements. ^In cases 9955** where there exist loops with no available statistics, this function behaves 9956** as if the loop did not exist - it returns non-zero and leave the variable 9957** that pOut points to unchanged. 9958** 9959** See also: [sqlite3_stmt_scanstatus_reset()] 9960*/ 9961int sqlite3_stmt_scanstatus( 9962 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 9963 int idx, /* Index of loop to report on */ 9964 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 9965 void *pOut /* Result written here */ 9966); 9967 9968/* 9969** CAPI3REF: Zero Scan-Status Counters 9970** METHOD: sqlite3_stmt 9971** 9972** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 9973** 9974** This API is only available if the library is built with pre-processor 9975** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 9976*/ 9977void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 9978 9979/* 9980** CAPI3REF: Flush caches to disk mid-transaction 9981** METHOD: sqlite3 9982** 9983** ^If a write-transaction is open on [database connection] D when the 9984** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 9985** pages in the pager-cache that are not currently in use are written out 9986** to disk. A dirty page may be in use if a database cursor created by an 9987** active SQL statement is reading from it, or if it is page 1 of a database 9988** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 9989** interface flushes caches for all schemas - "main", "temp", and 9990** any [attached] databases. 9991** 9992** ^If this function needs to obtain extra database locks before dirty pages 9993** can be flushed to disk, it does so. ^If those locks cannot be obtained 9994** immediately and there is a busy-handler callback configured, it is invoked 9995** in the usual manner. ^If the required lock still cannot be obtained, then 9996** the database is skipped and an attempt made to flush any dirty pages 9997** belonging to the next (if any) database. ^If any databases are skipped 9998** because locks cannot be obtained, but no other error occurs, this 9999** function returns SQLITE_BUSY. 10000** 10001** ^If any other error occurs while flushing dirty pages to disk (for 10002** example an IO error or out-of-memory condition), then processing is 10003** abandoned and an SQLite [error code] is returned to the caller immediately. 10004** 10005** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 10006** 10007** ^This function does not set the database handle error code or message 10008** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 10009*/ 10010int sqlite3_db_cacheflush(sqlite3*); 10011 10012/* 10013** CAPI3REF: The pre-update hook. 10014** METHOD: sqlite3 10015** 10016** ^These interfaces are only available if SQLite is compiled using the 10017** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 10018** 10019** ^The [sqlite3_preupdate_hook()] interface registers a callback function 10020** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 10021** on a database table. 10022** ^At most one preupdate hook may be registered at a time on a single 10023** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 10024** the previous setting. 10025** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 10026** with a NULL pointer as the second parameter. 10027** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 10028** the first parameter to callbacks. 10029** 10030** ^The preupdate hook only fires for changes to real database tables; the 10031** preupdate hook is not invoked for changes to [virtual tables] or to 10032** system tables like sqlite_sequence or sqlite_stat1. 10033** 10034** ^The second parameter to the preupdate callback is a pointer to 10035** the [database connection] that registered the preupdate hook. 10036** ^The third parameter to the preupdate callback is one of the constants 10037** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 10038** kind of update operation that is about to occur. 10039** ^(The fourth parameter to the preupdate callback is the name of the 10040** database within the database connection that is being modified. This 10041** will be "main" for the main database or "temp" for TEMP tables or 10042** the name given after the AS keyword in the [ATTACH] statement for attached 10043** databases.)^ 10044** ^The fifth parameter to the preupdate callback is the name of the 10045** table that is being modified. 10046** 10047** For an UPDATE or DELETE operation on a [rowid table], the sixth 10048** parameter passed to the preupdate callback is the initial [rowid] of the 10049** row being modified or deleted. For an INSERT operation on a rowid table, 10050** or any operation on a WITHOUT ROWID table, the value of the sixth 10051** parameter is undefined. For an INSERT or UPDATE on a rowid table the 10052** seventh parameter is the final rowid value of the row being inserted 10053** or updated. The value of the seventh parameter passed to the callback 10054** function is not defined for operations on WITHOUT ROWID tables, or for 10055** DELETE operations on rowid tables. 10056** 10057** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 10058** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 10059** provide additional information about a preupdate event. These routines 10060** may only be called from within a preupdate callback. Invoking any of 10061** these routines from outside of a preupdate callback or with a 10062** [database connection] pointer that is different from the one supplied 10063** to the preupdate callback results in undefined and probably undesirable 10064** behavior. 10065** 10066** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 10067** in the row that is being inserted, updated, or deleted. 10068** 10069** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 10070** a [protected sqlite3_value] that contains the value of the Nth column of 10071** the table row before it is updated. The N parameter must be between 0 10072** and one less than the number of columns or the behavior will be 10073** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 10074** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 10075** behavior is undefined. The [sqlite3_value] that P points to 10076** will be destroyed when the preupdate callback returns. 10077** 10078** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 10079** a [protected sqlite3_value] that contains the value of the Nth column of 10080** the table row after it is updated. The N parameter must be between 0 10081** and one less than the number of columns or the behavior will be 10082** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 10083** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 10084** behavior is undefined. The [sqlite3_value] that P points to 10085** will be destroyed when the preupdate callback returns. 10086** 10087** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 10088** callback was invoked as a result of a direct insert, update, or delete 10089** operation; or 1 for inserts, updates, or deletes invoked by top-level 10090** triggers; or 2 for changes resulting from triggers called by top-level 10091** triggers; and so forth. 10092** 10093** When the [sqlite3_blob_write()] API is used to update a blob column, 10094** the pre-update hook is invoked with SQLITE_DELETE. This is because the 10095** in this case the new values are not available. In this case, when a 10096** callback made with op==SQLITE_DELETE is actuall a write using the 10097** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns 10098** the index of the column being written. In other cases, where the 10099** pre-update hook is being invoked for some other reason, including a 10100** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. 10101** 10102** See also: [sqlite3_update_hook()] 10103*/ 10104#if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 10105void *sqlite3_preupdate_hook( 10106 sqlite3 *db, 10107 void(*xPreUpdate)( 10108 void *pCtx, /* Copy of third arg to preupdate_hook() */ 10109 sqlite3 *db, /* Database handle */ 10110 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 10111 char const *zDb, /* Database name */ 10112 char const *zName, /* Table name */ 10113 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 10114 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 10115 ), 10116 void* 10117); 10118int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 10119int sqlite3_preupdate_count(sqlite3 *); 10120int sqlite3_preupdate_depth(sqlite3 *); 10121int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 10122int sqlite3_preupdate_blobwrite(sqlite3 *); 10123#endif 10124 10125/* 10126** CAPI3REF: Low-level system error code 10127** METHOD: sqlite3 10128** 10129** ^Attempt to return the underlying operating system error code or error 10130** number that caused the most recent I/O error or failure to open a file. 10131** The return value is OS-dependent. For example, on unix systems, after 10132** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 10133** called to get back the underlying "errno" that caused the problem, such 10134** as ENOSPC, EAUTH, EISDIR, and so forth. 10135*/ 10136int sqlite3_system_errno(sqlite3*); 10137 10138/* 10139** CAPI3REF: Database Snapshot 10140** KEYWORDS: {snapshot} {sqlite3_snapshot} 10141** 10142** An instance of the snapshot object records the state of a [WAL mode] 10143** database for some specific point in history. 10144** 10145** In [WAL mode], multiple [database connections] that are open on the 10146** same database file can each be reading a different historical version 10147** of the database file. When a [database connection] begins a read 10148** transaction, that connection sees an unchanging copy of the database 10149** as it existed for the point in time when the transaction first started. 10150** Subsequent changes to the database from other connections are not seen 10151** by the reader until a new read transaction is started. 10152** 10153** The sqlite3_snapshot object records state information about an historical 10154** version of the database file so that it is possible to later open a new read 10155** transaction that sees that historical version of the database rather than 10156** the most recent version. 10157*/ 10158typedef struct sqlite3_snapshot { 10159 unsigned char hidden[48]; 10160} sqlite3_snapshot; 10161 10162/* 10163** CAPI3REF: Record A Database Snapshot 10164** CONSTRUCTOR: sqlite3_snapshot 10165** 10166** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 10167** new [sqlite3_snapshot] object that records the current state of 10168** schema S in database connection D. ^On success, the 10169** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 10170** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 10171** If there is not already a read-transaction open on schema S when 10172** this function is called, one is opened automatically. 10173** 10174** The following must be true for this function to succeed. If any of 10175** the following statements are false when sqlite3_snapshot_get() is 10176** called, SQLITE_ERROR is returned. The final value of *P is undefined 10177** in this case. 10178** 10179** <ul> 10180** <li> The database handle must not be in [autocommit mode]. 10181** 10182** <li> Schema S of [database connection] D must be a [WAL mode] database. 10183** 10184** <li> There must not be a write transaction open on schema S of database 10185** connection D. 10186** 10187** <li> One or more transactions must have been written to the current wal 10188** file since it was created on disk (by any connection). This means 10189** that a snapshot cannot be taken on a wal mode database with no wal 10190** file immediately after it is first opened. At least one transaction 10191** must be written to it first. 10192** </ul> 10193** 10194** This function may also return SQLITE_NOMEM. If it is called with the 10195** database handle in autocommit mode but fails for some other reason, 10196** whether or not a read transaction is opened on schema S is undefined. 10197** 10198** The [sqlite3_snapshot] object returned from a successful call to 10199** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 10200** to avoid a memory leak. 10201** 10202** The [sqlite3_snapshot_get()] interface is only available when the 10203** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10204*/ 10205SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 10206 sqlite3 *db, 10207 const char *zSchema, 10208 sqlite3_snapshot **ppSnapshot 10209); 10210 10211/* 10212** CAPI3REF: Start a read transaction on an historical snapshot 10213** METHOD: sqlite3_snapshot 10214** 10215** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 10216** transaction or upgrades an existing one for schema S of 10217** [database connection] D such that the read transaction refers to 10218** historical [snapshot] P, rather than the most recent change to the 10219** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 10220** on success or an appropriate [error code] if it fails. 10221** 10222** ^In order to succeed, the database connection must not be in 10223** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 10224** is already a read transaction open on schema S, then the database handle 10225** must have no active statements (SELECT statements that have been passed 10226** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 10227** SQLITE_ERROR is returned if either of these conditions is violated, or 10228** if schema S does not exist, or if the snapshot object is invalid. 10229** 10230** ^A call to sqlite3_snapshot_open() will fail to open if the specified 10231** snapshot has been overwritten by a [checkpoint]. In this case 10232** SQLITE_ERROR_SNAPSHOT is returned. 10233** 10234** If there is already a read transaction open when this function is 10235** invoked, then the same read transaction remains open (on the same 10236** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 10237** is returned. If another error code - for example SQLITE_PROTOCOL or an 10238** SQLITE_IOERR error code - is returned, then the final state of the 10239** read transaction is undefined. If SQLITE_OK is returned, then the 10240** read transaction is now open on database snapshot P. 10241** 10242** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 10243** database connection D does not know that the database file for 10244** schema S is in [WAL mode]. A database connection might not know 10245** that the database file is in [WAL mode] if there has been no prior 10246** I/O on that database connection, or if the database entered [WAL mode] 10247** after the most recent I/O on the database connection.)^ 10248** (Hint: Run "[PRAGMA application_id]" against a newly opened 10249** database connection in order to make it ready to use snapshots.) 10250** 10251** The [sqlite3_snapshot_open()] interface is only available when the 10252** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10253*/ 10254SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 10255 sqlite3 *db, 10256 const char *zSchema, 10257 sqlite3_snapshot *pSnapshot 10258); 10259 10260/* 10261** CAPI3REF: Destroy a snapshot 10262** DESTRUCTOR: sqlite3_snapshot 10263** 10264** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 10265** The application must eventually free every [sqlite3_snapshot] object 10266** using this routine to avoid a memory leak. 10267** 10268** The [sqlite3_snapshot_free()] interface is only available when the 10269** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10270*/ 10271SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 10272 10273/* 10274** CAPI3REF: Compare the ages of two snapshot handles. 10275** METHOD: sqlite3_snapshot 10276** 10277** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 10278** of two valid snapshot handles. 10279** 10280** If the two snapshot handles are not associated with the same database 10281** file, the result of the comparison is undefined. 10282** 10283** Additionally, the result of the comparison is only valid if both of the 10284** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 10285** last time the wal file was deleted. The wal file is deleted when the 10286** database is changed back to rollback mode or when the number of database 10287** clients drops to zero. If either snapshot handle was obtained before the 10288** wal file was last deleted, the value returned by this function 10289** is undefined. 10290** 10291** Otherwise, this API returns a negative value if P1 refers to an older 10292** snapshot than P2, zero if the two handles refer to the same database 10293** snapshot, and a positive value if P1 is a newer snapshot than P2. 10294** 10295** This interface is only available if SQLite is compiled with the 10296** [SQLITE_ENABLE_SNAPSHOT] option. 10297*/ 10298SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 10299 sqlite3_snapshot *p1, 10300 sqlite3_snapshot *p2 10301); 10302 10303/* 10304** CAPI3REF: Recover snapshots from a wal file 10305** METHOD: sqlite3_snapshot 10306** 10307** If a [WAL file] remains on disk after all database connections close 10308** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 10309** or because the last process to have the database opened exited without 10310** calling [sqlite3_close()]) and a new connection is subsequently opened 10311** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 10312** will only be able to open the last transaction added to the WAL file 10313** even though the WAL file contains other valid transactions. 10314** 10315** This function attempts to scan the WAL file associated with database zDb 10316** of database handle db and make all valid snapshots available to 10317** sqlite3_snapshot_open(). It is an error if there is already a read 10318** transaction open on the database, or if the database is not a WAL mode 10319** database. 10320** 10321** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 10322** 10323** This interface is only available if SQLite is compiled with the 10324** [SQLITE_ENABLE_SNAPSHOT] option. 10325*/ 10326SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 10327 10328/* 10329** CAPI3REF: Serialize a database 10330** 10331** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 10332** that is a serialization of the S database on [database connection] D. 10333** If P is not a NULL pointer, then the size of the database in bytes 10334** is written into *P. 10335** 10336** For an ordinary on-disk database file, the serialization is just a 10337** copy of the disk file. For an in-memory database or a "TEMP" database, 10338** the serialization is the same sequence of bytes which would be written 10339** to disk if that database where backed up to disk. 10340** 10341** The usual case is that sqlite3_serialize() copies the serialization of 10342** the database into memory obtained from [sqlite3_malloc64()] and returns 10343** a pointer to that memory. The caller is responsible for freeing the 10344** returned value to avoid a memory leak. However, if the F argument 10345** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 10346** are made, and the sqlite3_serialize() function will return a pointer 10347** to the contiguous memory representation of the database that SQLite 10348** is currently using for that database, or NULL if the no such contiguous 10349** memory representation of the database exists. A contiguous memory 10350** representation of the database will usually only exist if there has 10351** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 10352** values of D and S. 10353** The size of the database is written into *P even if the 10354** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 10355** of the database exists. 10356** 10357** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 10358** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 10359** allocation error occurs. 10360** 10361** This interface is omitted if SQLite is compiled with the 10362** [SQLITE_OMIT_DESERIALIZE] option. 10363*/ 10364unsigned char *sqlite3_serialize( 10365 sqlite3 *db, /* The database connection */ 10366 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 10367 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 10368 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 10369); 10370 10371/* 10372** CAPI3REF: Flags for sqlite3_serialize 10373** 10374** Zero or more of the following constants can be OR-ed together for 10375** the F argument to [sqlite3_serialize(D,S,P,F)]. 10376** 10377** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 10378** a pointer to contiguous in-memory database that it is currently using, 10379** without making a copy of the database. If SQLite is not currently using 10380** a contiguous in-memory database, then this option causes 10381** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 10382** using a contiguous in-memory database if it has been initialized by a 10383** prior call to [sqlite3_deserialize()]. 10384*/ 10385#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 10386 10387/* 10388** CAPI3REF: Deserialize a database 10389** 10390** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 10391** [database connection] D to disconnect from database S and then 10392** reopen S as an in-memory database based on the serialization contained 10393** in P. The serialized database P is N bytes in size. M is the size of 10394** the buffer P, which might be larger than N. If M is larger than N, and 10395** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 10396** permitted to add content to the in-memory database as long as the total 10397** size does not exceed M bytes. 10398** 10399** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 10400** invoke sqlite3_free() on the serialization buffer when the database 10401** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 10402** SQLite will try to increase the buffer size using sqlite3_realloc64() 10403** if writes on the database cause it to grow larger than M bytes. 10404** 10405** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 10406** database is currently in a read transaction or is involved in a backup 10407** operation. 10408** 10409** It is not possible to deserialized into the TEMP database. If the 10410** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the 10411** function returns SQLITE_ERROR. 10412** 10413** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 10414** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 10415** [sqlite3_free()] is invoked on argument P prior to returning. 10416** 10417** This interface is omitted if SQLite is compiled with the 10418** [SQLITE_OMIT_DESERIALIZE] option. 10419*/ 10420int sqlite3_deserialize( 10421 sqlite3 *db, /* The database connection */ 10422 const char *zSchema, /* Which DB to reopen with the deserialization */ 10423 unsigned char *pData, /* The serialized database content */ 10424 sqlite3_int64 szDb, /* Number bytes in the deserialization */ 10425 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 10426 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 10427); 10428 10429/* 10430** CAPI3REF: Flags for sqlite3_deserialize() 10431** 10432** The following are allowed values for 6th argument (the F argument) to 10433** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 10434** 10435** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 10436** in the P argument is held in memory obtained from [sqlite3_malloc64()] 10437** and that SQLite should take ownership of this memory and automatically 10438** free it when it has finished using it. Without this flag, the caller 10439** is responsible for freeing any dynamically allocated memory. 10440** 10441** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 10442** grow the size of the database using calls to [sqlite3_realloc64()]. This 10443** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 10444** Without this flag, the deserialized database cannot increase in size beyond 10445** the number of bytes specified by the M parameter. 10446** 10447** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 10448** should be treated as read-only. 10449*/ 10450#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 10451#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 10452#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 10453 10454/* 10455** Undo the hack that converts floating point types to integer for 10456** builds on processors without floating point support. 10457*/ 10458#ifdef SQLITE_OMIT_FLOATING_POINT 10459# undef double 10460#endif 10461 10462#ifdef __cplusplus 10463} /* End of the 'extern "C"' block */ 10464#endif 10465#endif /* SQLITE3_H */ 10466