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_CANTOPEN_EXISTS (SQLITE_CANTOPEN | (7<<8)) 543#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 544#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 545#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 546#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 547#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 548#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 549#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 550#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 551#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 552#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 553#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 554#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 555#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 556#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 557#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 558#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 559#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 560#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 561#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 562#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 563#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<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)) 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#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 579#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 580#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 581#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 582#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 583#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 584#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 585#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 586#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 587#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 588#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 589#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 590#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 591#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 592#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 593#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 594#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 595#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 596#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 597#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 598#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 599 600/* Reserved: 0x00F00000 */ 601/* Legacy compatibility: */ 602#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 603 604 605/* 606** CAPI3REF: Device Characteristics 607** 608** The xDeviceCharacteristics method of the [sqlite3_io_methods] 609** object returns an integer which is a vector of these 610** bit values expressing I/O characteristics of the mass storage 611** device that holds the file that the [sqlite3_io_methods] 612** refers to. 613** 614** The SQLITE_IOCAP_ATOMIC property means that all writes of 615** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 616** mean that writes of blocks that are nnn bytes in size and 617** are aligned to an address which is an integer multiple of 618** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 619** that when data is appended to a file, the data is appended 620** first then the size of the file is extended, never the other 621** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 622** information is written to disk in the same order as calls 623** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 624** after reboot following a crash or power loss, the only bytes in a 625** file that were written at the application level might have changed 626** and that adjacent bytes, even bytes within the same sector are 627** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 628** flag indicates that a file cannot be deleted when open. The 629** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 630** read-only media and cannot be changed even by processes with 631** elevated privileges. 632** 633** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 634** filesystem supports doing multiple write operations atomically when those 635** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 636** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 637*/ 638#define SQLITE_IOCAP_ATOMIC 0x00000001 639#define SQLITE_IOCAP_ATOMIC512 0x00000002 640#define SQLITE_IOCAP_ATOMIC1K 0x00000004 641#define SQLITE_IOCAP_ATOMIC2K 0x00000008 642#define SQLITE_IOCAP_ATOMIC4K 0x00000010 643#define SQLITE_IOCAP_ATOMIC8K 0x00000020 644#define SQLITE_IOCAP_ATOMIC16K 0x00000040 645#define SQLITE_IOCAP_ATOMIC32K 0x00000080 646#define SQLITE_IOCAP_ATOMIC64K 0x00000100 647#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 648#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 649#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 650#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 651#define SQLITE_IOCAP_IMMUTABLE 0x00002000 652#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 653 654/* 655** CAPI3REF: File Locking Levels 656** 657** SQLite uses one of these integer values as the second 658** argument to calls it makes to the xLock() and xUnlock() methods 659** of an [sqlite3_io_methods] object. 660*/ 661#define SQLITE_LOCK_NONE 0 662#define SQLITE_LOCK_SHARED 1 663#define SQLITE_LOCK_RESERVED 2 664#define SQLITE_LOCK_PENDING 3 665#define SQLITE_LOCK_EXCLUSIVE 4 666 667/* 668** CAPI3REF: Synchronization Type Flags 669** 670** When SQLite invokes the xSync() method of an 671** [sqlite3_io_methods] object it uses a combination of 672** these integer values as the second argument. 673** 674** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 675** sync operation only needs to flush data to mass storage. Inode 676** information need not be flushed. If the lower four bits of the flag 677** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 678** If the lower four bits equal SQLITE_SYNC_FULL, that means 679** to use Mac OS X style fullsync instead of fsync(). 680** 681** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 682** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 683** settings. The [synchronous pragma] determines when calls to the 684** xSync VFS method occur and applies uniformly across all platforms. 685** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 686** energetic or rigorous or forceful the sync operations are and 687** only make a difference on Mac OSX for the default SQLite code. 688** (Third-party VFS implementations might also make the distinction 689** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 690** operating systems natively supported by SQLite, only Mac OSX 691** cares about the difference.) 692*/ 693#define SQLITE_SYNC_NORMAL 0x00002 694#define SQLITE_SYNC_FULL 0x00003 695#define SQLITE_SYNC_DATAONLY 0x00010 696 697/* 698** CAPI3REF: OS Interface Open File Handle 699** 700** An [sqlite3_file] object represents an open file in the 701** [sqlite3_vfs | OS interface layer]. Individual OS interface 702** implementations will 703** want to subclass this object by appending additional fields 704** for their own use. The pMethods entry is a pointer to an 705** [sqlite3_io_methods] object that defines methods for performing 706** I/O operations on the open file. 707*/ 708typedef struct sqlite3_file sqlite3_file; 709struct sqlite3_file { 710 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 711}; 712 713/* 714** CAPI3REF: OS Interface File Virtual Methods Object 715** 716** Every file opened by the [sqlite3_vfs.xOpen] method populates an 717** [sqlite3_file] object (or, more commonly, a subclass of the 718** [sqlite3_file] object) with a pointer to an instance of this object. 719** This object defines the methods used to perform various operations 720** against the open file represented by the [sqlite3_file] object. 721** 722** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 723** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 724** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 725** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 726** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 727** to NULL. 728** 729** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 730** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 731** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 732** flag may be ORed in to indicate that only the data of the file 733** and not its inode needs to be synced. 734** 735** The integer values to xLock() and xUnlock() are one of 736** <ul> 737** <li> [SQLITE_LOCK_NONE], 738** <li> [SQLITE_LOCK_SHARED], 739** <li> [SQLITE_LOCK_RESERVED], 740** <li> [SQLITE_LOCK_PENDING], or 741** <li> [SQLITE_LOCK_EXCLUSIVE]. 742** </ul> 743** xLock() increases the lock. xUnlock() decreases the lock. 744** The xCheckReservedLock() method checks whether any database connection, 745** either in this process or in some other process, is holding a RESERVED, 746** PENDING, or EXCLUSIVE lock on the file. It returns true 747** if such a lock exists and false otherwise. 748** 749** The xFileControl() method is a generic interface that allows custom 750** VFS implementations to directly control an open file using the 751** [sqlite3_file_control()] interface. The second "op" argument is an 752** integer opcode. The third argument is a generic pointer intended to 753** point to a structure that may contain arguments or space in which to 754** write return values. Potential uses for xFileControl() might be 755** functions to enable blocking locks with timeouts, to change the 756** locking strategy (for example to use dot-file locks), to inquire 757** about the status of a lock, or to break stale locks. The SQLite 758** core reserves all opcodes less than 100 for its own use. 759** A [file control opcodes | list of opcodes] less than 100 is available. 760** Applications that define a custom xFileControl method should use opcodes 761** greater than 100 to avoid conflicts. VFS implementations should 762** return [SQLITE_NOTFOUND] for file control opcodes that they do not 763** recognize. 764** 765** The xSectorSize() method returns the sector size of the 766** device that underlies the file. The sector size is the 767** minimum write that can be performed without disturbing 768** other bytes in the file. The xDeviceCharacteristics() 769** method returns a bit vector describing behaviors of the 770** underlying device: 771** 772** <ul> 773** <li> [SQLITE_IOCAP_ATOMIC] 774** <li> [SQLITE_IOCAP_ATOMIC512] 775** <li> [SQLITE_IOCAP_ATOMIC1K] 776** <li> [SQLITE_IOCAP_ATOMIC2K] 777** <li> [SQLITE_IOCAP_ATOMIC4K] 778** <li> [SQLITE_IOCAP_ATOMIC8K] 779** <li> [SQLITE_IOCAP_ATOMIC16K] 780** <li> [SQLITE_IOCAP_ATOMIC32K] 781** <li> [SQLITE_IOCAP_ATOMIC64K] 782** <li> [SQLITE_IOCAP_SAFE_APPEND] 783** <li> [SQLITE_IOCAP_SEQUENTIAL] 784** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 785** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 786** <li> [SQLITE_IOCAP_IMMUTABLE] 787** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 788** </ul> 789** 790** The SQLITE_IOCAP_ATOMIC property means that all writes of 791** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 792** mean that writes of blocks that are nnn bytes in size and 793** are aligned to an address which is an integer multiple of 794** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 795** that when data is appended to a file, the data is appended 796** first then the size of the file is extended, never the other 797** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 798** information is written to disk in the same order as calls 799** to xWrite(). 800** 801** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 802** in the unread portions of the buffer with zeros. A VFS that 803** fails to zero-fill short reads might seem to work. However, 804** failure to zero-fill short reads will eventually lead to 805** database corruption. 806*/ 807typedef struct sqlite3_io_methods sqlite3_io_methods; 808struct sqlite3_io_methods { 809 int iVersion; 810 int (*xClose)(sqlite3_file*); 811 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 812 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 813 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 814 int (*xSync)(sqlite3_file*, int flags); 815 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 816 int (*xLock)(sqlite3_file*, int); 817 int (*xUnlock)(sqlite3_file*, int); 818 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 819 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 820 int (*xSectorSize)(sqlite3_file*); 821 int (*xDeviceCharacteristics)(sqlite3_file*); 822 /* Methods above are valid for version 1 */ 823 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 824 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 825 void (*xShmBarrier)(sqlite3_file*); 826 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 827 /* Methods above are valid for version 2 */ 828 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 829 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 830 /* Methods above are valid for version 3 */ 831 /* Additional methods may be added in future releases */ 832}; 833 834/* 835** CAPI3REF: Standard File Control Opcodes 836** KEYWORDS: {file control opcodes} {file control opcode} 837** 838** These integer constants are opcodes for the xFileControl method 839** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 840** interface. 841** 842** <ul> 843** <li>[[SQLITE_FCNTL_LOCKSTATE]] 844** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 845** opcode causes the xFileControl method to write the current state of 846** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 847** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 848** into an integer that the pArg argument points to. This capability 849** is used during testing and is only available when the SQLITE_TEST 850** compile-time option is used. 851** 852** <li>[[SQLITE_FCNTL_SIZE_HINT]] 853** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 854** layer a hint of how large the database file will grow to be during the 855** current transaction. This hint is not guaranteed to be accurate but it 856** is often close. The underlying VFS might choose to preallocate database 857** file space based on this hint in order to help writes to the database 858** file run faster. 859** 860** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 861** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 862** implements [sqlite3_deserialize()] to set an upper bound on the size 863** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 864** If the integer pointed to is negative, then it is filled in with the 865** current limit. Otherwise the limit is set to the larger of the value 866** of the integer pointed to and the current database size. The integer 867** pointed to is set to the new limit. 868** 869** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 870** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 871** extends and truncates the database file in chunks of a size specified 872** by the user. The fourth argument to [sqlite3_file_control()] should 873** point to an integer (type int) containing the new chunk-size to use 874** for the nominated database. Allocating database file space in large 875** chunks (say 1MB at a time), may reduce file-system fragmentation and 876** improve performance on some systems. 877** 878** <li>[[SQLITE_FCNTL_FILE_POINTER]] 879** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 880** to the [sqlite3_file] object associated with a particular database 881** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 882** 883** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 884** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 885** to the [sqlite3_file] object associated with the journal file (either 886** the [rollback journal] or the [write-ahead log]) for a particular database 887** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 888** 889** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 890** No longer in use. 891** 892** <li>[[SQLITE_FCNTL_SYNC]] 893** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 894** sent to the VFS immediately before the xSync method is invoked on a 895** database file descriptor. Or, if the xSync method is not invoked 896** because the user has configured SQLite with 897** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 898** of the xSync method. In most cases, the pointer argument passed with 899** this file-control is NULL. However, if the database file is being synced 900** as part of a multi-database commit, the argument points to a nul-terminated 901** string containing the transactions super-journal file name. VFSes that 902** do not need this signal should silently ignore this opcode. Applications 903** should not call [sqlite3_file_control()] with this opcode as doing so may 904** disrupt the operation of the specialized VFSes that do require it. 905** 906** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 907** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 908** and sent to the VFS after a transaction has been committed immediately 909** but before the database is unlocked. VFSes that do not need this signal 910** should silently ignore this opcode. Applications should not call 911** [sqlite3_file_control()] with this opcode as doing so may disrupt the 912** operation of the specialized VFSes that do require it. 913** 914** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 915** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 916** retry counts and intervals for certain disk I/O operations for the 917** windows [VFS] in order to provide robustness in the presence of 918** anti-virus programs. By default, the windows VFS will retry file read, 919** file write, and file delete operations up to 10 times, with a delay 920** of 25 milliseconds before the first retry and with the delay increasing 921** by an additional 25 milliseconds with each subsequent retry. This 922** opcode allows these two values (10 retries and 25 milliseconds of delay) 923** to be adjusted. The values are changed for all database connections 924** within the same process. The argument is a pointer to an array of two 925** integers where the first integer is the new retry count and the second 926** integer is the delay. If either integer is negative, then the setting 927** is not changed but instead the prior value of that setting is written 928** into the array entry, allowing the current retry settings to be 929** interrogated. The zDbName parameter is ignored. 930** 931** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 932** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 933** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 934** write ahead log ([WAL file]) and shared memory 935** files used for transaction control 936** are automatically deleted when the latest connection to the database 937** closes. Setting persistent WAL mode causes those files to persist after 938** close. Persisting the files is useful when other processes that do not 939** have write permission on the directory containing the database file want 940** to read the database file, as the WAL and shared memory files must exist 941** in order for the database to be readable. The fourth parameter to 942** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 943** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 944** WAL mode. If the integer is -1, then it is overwritten with the current 945** WAL persistence setting. 946** 947** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 948** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 949** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 950** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 951** xDeviceCharacteristics methods. The fourth parameter to 952** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 953** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 954** mode. If the integer is -1, then it is overwritten with the current 955** zero-damage mode setting. 956** 957** <li>[[SQLITE_FCNTL_OVERWRITE]] 958** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 959** a write transaction to indicate that, unless it is rolled back for some 960** reason, the entire database file will be overwritten by the current 961** transaction. This is used by VACUUM operations. 962** 963** <li>[[SQLITE_FCNTL_VFSNAME]] 964** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 965** all [VFSes] in the VFS stack. The names are of all VFS shims and the 966** final bottom-level VFS are written into memory obtained from 967** [sqlite3_malloc()] and the result is stored in the char* variable 968** that the fourth parameter of [sqlite3_file_control()] points to. 969** The caller is responsible for freeing the memory when done. As with 970** all file-control actions, there is no guarantee that this will actually 971** do anything. Callers should initialize the char* variable to a NULL 972** pointer in case this file-control is not implemented. This file-control 973** is intended for diagnostic use only. 974** 975** <li>[[SQLITE_FCNTL_VFS_POINTER]] 976** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 977** [VFSes] currently in use. ^(The argument X in 978** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 979** of type "[sqlite3_vfs] **". This opcodes will set *X 980** to a pointer to the top-level VFS.)^ 981** ^When there are multiple VFS shims in the stack, this opcode finds the 982** upper-most shim only. 983** 984** <li>[[SQLITE_FCNTL_PRAGMA]] 985** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 986** file control is sent to the open [sqlite3_file] object corresponding 987** to the database file to which the pragma statement refers. ^The argument 988** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 989** pointers to strings (char**) in which the second element of the array 990** is the name of the pragma and the third element is the argument to the 991** pragma or NULL if the pragma has no argument. ^The handler for an 992** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 993** of the char** argument point to a string obtained from [sqlite3_mprintf()] 994** or the equivalent and that string will become the result of the pragma or 995** the error message if the pragma fails. ^If the 996** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 997** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 998** file control returns [SQLITE_OK], then the parser assumes that the 999** VFS has handled the PRAGMA itself and the parser generates a no-op 1000** prepared statement if result string is NULL, or that returns a copy 1001** of the result string if the string is non-NULL. 1002** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 1003** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 1004** that the VFS encountered an error while handling the [PRAGMA] and the 1005** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 1006** file control occurs at the beginning of pragma statement analysis and so 1007** it is able to override built-in [PRAGMA] statements. 1008** 1009** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 1010** ^The [SQLITE_FCNTL_BUSYHANDLER] 1011** file-control may be invoked by SQLite on the database file handle 1012** shortly after it is opened in order to provide a custom VFS with access 1013** to the connection's busy-handler callback. The argument is of type (void**) 1014** - an array of two (void *) values. The first (void *) actually points 1015** to a function of type (int (*)(void *)). In order to invoke the connection's 1016** busy-handler, this function should be invoked with the second (void *) in 1017** the array as the only argument. If it returns non-zero, then the operation 1018** should be retried. If it returns zero, the custom VFS should abandon the 1019** current operation. 1020** 1021** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 1022** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 1023** to have SQLite generate a 1024** temporary filename using the same algorithm that is followed to generate 1025** temporary filenames for TEMP tables and other internal uses. The 1026** argument should be a char** which will be filled with the filename 1027** written into memory obtained from [sqlite3_malloc()]. The caller should 1028** invoke [sqlite3_free()] on the result to avoid a memory leak. 1029** 1030** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1031** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1032** maximum number of bytes that will be used for memory-mapped I/O. 1033** The argument is a pointer to a value of type sqlite3_int64 that 1034** is an advisory maximum number of bytes in the file to memory map. The 1035** pointer is overwritten with the old value. The limit is not changed if 1036** the value originally pointed to is negative, and so the current limit 1037** can be queried by passing in a pointer to a negative number. This 1038** file-control is used internally to implement [PRAGMA mmap_size]. 1039** 1040** <li>[[SQLITE_FCNTL_TRACE]] 1041** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1042** to the VFS about what the higher layers of the SQLite stack are doing. 1043** This file control is used by some VFS activity tracing [shims]. 1044** The argument is a zero-terminated string. Higher layers in the 1045** SQLite stack may generate instances of this file control if 1046** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1047** 1048** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1049** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1050** pointer to an integer and it writes a boolean into that integer depending 1051** on whether or not the file has been renamed, moved, or deleted since it 1052** was first opened. 1053** 1054** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1055** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1056** underlying native file handle associated with a file handle. This file 1057** control interprets its argument as a pointer to a native file handle and 1058** writes the resulting value there. 1059** 1060** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1061** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1062** opcode causes the xFileControl method to swap the file handle with the one 1063** pointed to by the pArg argument. This capability is used during testing 1064** and only needs to be supported when SQLITE_TEST is defined. 1065** 1066** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1067** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1068** be advantageous to block on the next WAL lock if the lock is not immediately 1069** available. The WAL subsystem issues this signal during rare 1070** circumstances in order to fix a problem with priority inversion. 1071** Applications should <em>not</em> use this file-control. 1072** 1073** <li>[[SQLITE_FCNTL_ZIPVFS]] 1074** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1075** VFS should return SQLITE_NOTFOUND for this opcode. 1076** 1077** <li>[[SQLITE_FCNTL_RBU]] 1078** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1079** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1080** this opcode. 1081** 1082** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1083** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1084** the file descriptor is placed in "batch write mode", which 1085** means all subsequent write operations will be deferred and done 1086** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1087** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1088** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1089** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1090** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1091** no VFS interface calls on the same [sqlite3_file] file descriptor 1092** except for calls to the xWrite method and the xFileControl method 1093** with [SQLITE_FCNTL_SIZE_HINT]. 1094** 1095** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1096** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1097** operations since the previous successful call to 1098** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1099** This file control returns [SQLITE_OK] if and only if the writes were 1100** all performed successfully and have been committed to persistent storage. 1101** ^Regardless of whether or not it is successful, this file control takes 1102** the file descriptor out of batch write mode so that all subsequent 1103** write operations are independent. 1104** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1105** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1106** 1107** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1108** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1109** operations since the previous successful call to 1110** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1111** ^This file control takes the file descriptor out of batch write mode 1112** so that all subsequent write operations are independent. 1113** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1114** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1115** 1116** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1117** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1118** to block for up to M milliseconds before failing when attempting to 1119** obtain a file lock using the xLock or xShmLock methods of the VFS. 1120** The parameter is a pointer to a 32-bit signed integer that contains 1121** the value that M is to be set to. Before returning, the 32-bit signed 1122** integer is overwritten with the previous value of M. 1123** 1124** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1125** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1126** a database file. The argument is a pointer to a 32-bit unsigned integer. 1127** The "data version" for the pager is written into the pointer. The 1128** "data version" changes whenever any change occurs to the corresponding 1129** database file, either through SQL statements on the same database 1130** connection or through transactions committed by separate database 1131** connections possibly in other processes. The [sqlite3_total_changes()] 1132** interface can be used to find if any database on the connection has changed, 1133** but that interface responds to changes on TEMP as well as MAIN and does 1134** not provide a mechanism to detect changes to MAIN only. Also, the 1135** [sqlite3_total_changes()] interface responds to internal changes only and 1136** omits changes made by other database connections. The 1137** [PRAGMA data_version] command provides a mechanism to detect changes to 1138** a single attached database that occur due to other database connections, 1139** but omits changes implemented by the database connection on which it is 1140** called. This file control is the only mechanism to detect changes that 1141** happen either internally or externally and that are associated with 1142** a particular attached database. 1143** 1144** <li>[[SQLITE_FCNTL_CKPT_START]] 1145** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1146** in wal mode before the client starts to copy pages from the wal 1147** file to the database file. 1148** 1149** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1150** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1151** in wal mode after the client has finished copying pages from the wal 1152** file to the database file, but before the *-shm file is updated to 1153** record the fact that the pages have been checkpointed. 1154** </ul> 1155** 1156** <li>[[SQLITE_FCNTL_EXTERNAL_READER]] 1157** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect 1158** whether or not there is a database client in another process with a wal-mode 1159** transaction open on the database or not. It is only available on unix.The 1160** (void*) argument passed with this file-control should be a pointer to a 1161** value of type (int). The integer value is set to 1 if the database is a wal 1162** mode database and there exists at least one client in another process that 1163** currently has an SQL transaction open on the database. It is set to 0 if 1164** the database is not a wal-mode db, or if there is no such connection in any 1165** other process. This opcode cannot be used to detect transactions opened 1166** by clients within the current process, only within other processes. 1167** </ul> 1168** 1169** <li>[[SQLITE_FCNTL_CKSM_FILE]] 1170** Used by the cksmvfs VFS module only. 1171** </ul> 1172*/ 1173#define SQLITE_FCNTL_LOCKSTATE 1 1174#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1175#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1176#define SQLITE_FCNTL_LAST_ERRNO 4 1177#define SQLITE_FCNTL_SIZE_HINT 5 1178#define SQLITE_FCNTL_CHUNK_SIZE 6 1179#define SQLITE_FCNTL_FILE_POINTER 7 1180#define SQLITE_FCNTL_SYNC_OMITTED 8 1181#define SQLITE_FCNTL_WIN32_AV_RETRY 9 1182#define SQLITE_FCNTL_PERSIST_WAL 10 1183#define SQLITE_FCNTL_OVERWRITE 11 1184#define SQLITE_FCNTL_VFSNAME 12 1185#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1186#define SQLITE_FCNTL_PRAGMA 14 1187#define SQLITE_FCNTL_BUSYHANDLER 15 1188#define SQLITE_FCNTL_TEMPFILENAME 16 1189#define SQLITE_FCNTL_MMAP_SIZE 18 1190#define SQLITE_FCNTL_TRACE 19 1191#define SQLITE_FCNTL_HAS_MOVED 20 1192#define SQLITE_FCNTL_SYNC 21 1193#define SQLITE_FCNTL_COMMIT_PHASETWO 22 1194#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1195#define SQLITE_FCNTL_WAL_BLOCK 24 1196#define SQLITE_FCNTL_ZIPVFS 25 1197#define SQLITE_FCNTL_RBU 26 1198#define SQLITE_FCNTL_VFS_POINTER 27 1199#define SQLITE_FCNTL_JOURNAL_POINTER 28 1200#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1201#define SQLITE_FCNTL_PDB 30 1202#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1203#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1204#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1205#define SQLITE_FCNTL_LOCK_TIMEOUT 34 1206#define SQLITE_FCNTL_DATA_VERSION 35 1207#define SQLITE_FCNTL_SIZE_LIMIT 36 1208#define SQLITE_FCNTL_CKPT_DONE 37 1209#define SQLITE_FCNTL_RESERVE_BYTES 38 1210#define SQLITE_FCNTL_CKPT_START 39 1211#define SQLITE_FCNTL_EXTERNAL_READER 40 1212#define SQLITE_FCNTL_CKSM_FILE 41 1213 1214/* deprecated names */ 1215#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1216#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1217#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1218 1219 1220/* 1221** CAPI3REF: Mutex Handle 1222** 1223** The mutex module within SQLite defines [sqlite3_mutex] to be an 1224** abstract type for a mutex object. The SQLite core never looks 1225** at the internal representation of an [sqlite3_mutex]. It only 1226** deals with pointers to the [sqlite3_mutex] object. 1227** 1228** Mutexes are created using [sqlite3_mutex_alloc()]. 1229*/ 1230typedef struct sqlite3_mutex sqlite3_mutex; 1231 1232/* 1233** CAPI3REF: Loadable Extension Thunk 1234** 1235** A pointer to the opaque sqlite3_api_routines structure is passed as 1236** the third parameter to entry points of [loadable extensions]. This 1237** structure must be typedefed in order to work around compiler warnings 1238** on some platforms. 1239*/ 1240typedef struct sqlite3_api_routines sqlite3_api_routines; 1241 1242/* 1243** CAPI3REF: OS Interface Object 1244** 1245** An instance of the sqlite3_vfs object defines the interface between 1246** the SQLite core and the underlying operating system. The "vfs" 1247** in the name of the object stands for "virtual file system". See 1248** the [VFS | VFS documentation] for further information. 1249** 1250** The VFS interface is sometimes extended by adding new methods onto 1251** the end. Each time such an extension occurs, the iVersion field 1252** is incremented. The iVersion value started out as 1 in 1253** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1254** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1255** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1256** may be appended to the sqlite3_vfs object and the iVersion value 1257** may increase again in future versions of SQLite. 1258** Note that due to an oversight, the structure 1259** of the sqlite3_vfs object changed in the transition from 1260** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1261** and yet the iVersion field was not increased. 1262** 1263** The szOsFile field is the size of the subclassed [sqlite3_file] 1264** structure used by this VFS. mxPathname is the maximum length of 1265** a pathname in this VFS. 1266** 1267** Registered sqlite3_vfs objects are kept on a linked list formed by 1268** the pNext pointer. The [sqlite3_vfs_register()] 1269** and [sqlite3_vfs_unregister()] interfaces manage this list 1270** in a thread-safe way. The [sqlite3_vfs_find()] interface 1271** searches the list. Neither the application code nor the VFS 1272** implementation should use the pNext pointer. 1273** 1274** The pNext field is the only field in the sqlite3_vfs 1275** structure that SQLite will ever modify. SQLite will only access 1276** or modify this field while holding a particular static mutex. 1277** The application should never modify anything within the sqlite3_vfs 1278** object once the object has been registered. 1279** 1280** The zName field holds the name of the VFS module. The name must 1281** be unique across all VFS modules. 1282** 1283** [[sqlite3_vfs.xOpen]] 1284** ^SQLite guarantees that the zFilename parameter to xOpen 1285** is either a NULL pointer or string obtained 1286** from xFullPathname() with an optional suffix added. 1287** ^If a suffix is added to the zFilename parameter, it will 1288** consist of a single "-" character followed by no more than 1289** 11 alphanumeric and/or "-" characters. 1290** ^SQLite further guarantees that 1291** the string will be valid and unchanged until xClose() is 1292** called. Because of the previous sentence, 1293** the [sqlite3_file] can safely store a pointer to the 1294** filename if it needs to remember the filename for some reason. 1295** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1296** must invent its own temporary name for the file. ^Whenever the 1297** xFilename parameter is NULL it will also be the case that the 1298** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1299** 1300** The flags argument to xOpen() includes all bits set in 1301** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1302** or [sqlite3_open16()] is used, then flags includes at least 1303** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1304** If xOpen() opens a file read-only then it sets *pOutFlags to 1305** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1306** 1307** ^(SQLite will also add one of the following flags to the xOpen() 1308** call, depending on the object being opened: 1309** 1310** <ul> 1311** <li> [SQLITE_OPEN_MAIN_DB] 1312** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1313** <li> [SQLITE_OPEN_TEMP_DB] 1314** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1315** <li> [SQLITE_OPEN_TRANSIENT_DB] 1316** <li> [SQLITE_OPEN_SUBJOURNAL] 1317** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1318** <li> [SQLITE_OPEN_WAL] 1319** </ul>)^ 1320** 1321** The file I/O implementation can use the object type flags to 1322** change the way it deals with files. For example, an application 1323** that does not care about crash recovery or rollback might make 1324** the open of a journal file a no-op. Writes to this journal would 1325** also be no-ops, and any attempt to read the journal would return 1326** SQLITE_IOERR. Or the implementation might recognize that a database 1327** file will be doing page-aligned sector reads and writes in a random 1328** order and set up its I/O subsystem accordingly. 1329** 1330** SQLite might also add one of the following flags to the xOpen method: 1331** 1332** <ul> 1333** <li> [SQLITE_OPEN_DELETEONCLOSE] 1334** <li> [SQLITE_OPEN_EXCLUSIVE] 1335** </ul> 1336** 1337** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1338** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1339** will be set for TEMP databases and their journals, transient 1340** databases, and subjournals. 1341** 1342** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1343** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1344** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1345** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1346** SQLITE_OPEN_CREATE, is used to indicate that file should always 1347** be created, and that it is an error if it already exists. 1348** It is <i>not</i> used to indicate the file should be opened 1349** for exclusive access. 1350** 1351** ^At least szOsFile bytes of memory are allocated by SQLite 1352** to hold the [sqlite3_file] structure passed as the third 1353** argument to xOpen. The xOpen method does not have to 1354** allocate the structure; it should just fill it in. Note that 1355** the xOpen method must set the sqlite3_file.pMethods to either 1356** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1357** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1358** element will be valid after xOpen returns regardless of the success 1359** or failure of the xOpen call. 1360** 1361** [[sqlite3_vfs.xAccess]] 1362** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1363** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1364** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1365** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1366** flag is never actually used and is not implemented in the built-in 1367** VFSes of SQLite. The file is named by the second argument and can be a 1368** directory. The xAccess method returns [SQLITE_OK] on success or some 1369** non-zero error code if there is an I/O error or if the name of 1370** the file given in the second argument is illegal. If SQLITE_OK 1371** is returned, then non-zero or zero is written into *pResOut to indicate 1372** whether or not the file is accessible. 1373** 1374** ^SQLite will always allocate at least mxPathname+1 bytes for the 1375** output buffer xFullPathname. The exact size of the output buffer 1376** is also passed as a parameter to both methods. If the output buffer 1377** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1378** handled as a fatal error by SQLite, vfs implementations should endeavor 1379** to prevent this by setting mxPathname to a sufficiently large value. 1380** 1381** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1382** interfaces are not strictly a part of the filesystem, but they are 1383** included in the VFS structure for completeness. 1384** The xRandomness() function attempts to return nBytes bytes 1385** of good-quality randomness into zOut. The return value is 1386** the actual number of bytes of randomness obtained. 1387** The xSleep() method causes the calling thread to sleep for at 1388** least the number of microseconds given. ^The xCurrentTime() 1389** method returns a Julian Day Number for the current date and time as 1390** a floating point value. 1391** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1392** Day Number multiplied by 86400000 (the number of milliseconds in 1393** a 24-hour day). 1394** ^SQLite will use the xCurrentTimeInt64() method to get the current 1395** date and time if that method is available (if iVersion is 2 or 1396** greater and the function pointer is not NULL) and will fall back 1397** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1398** 1399** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1400** are not used by the SQLite core. These optional interfaces are provided 1401** by some VFSes to facilitate testing of the VFS code. By overriding 1402** system calls with functions under its control, a test program can 1403** simulate faults and error conditions that would otherwise be difficult 1404** or impossible to induce. The set of system calls that can be overridden 1405** varies from one VFS to another, and from one version of the same VFS to the 1406** next. Applications that use these interfaces must be prepared for any 1407** or all of these interfaces to be NULL or for their behavior to change 1408** from one release to the next. Applications must not attempt to access 1409** any of these methods if the iVersion of the VFS is less than 3. 1410*/ 1411typedef struct sqlite3_vfs sqlite3_vfs; 1412typedef void (*sqlite3_syscall_ptr)(void); 1413struct sqlite3_vfs { 1414 int iVersion; /* Structure version number (currently 3) */ 1415 int szOsFile; /* Size of subclassed sqlite3_file */ 1416 int mxPathname; /* Maximum file pathname length */ 1417 sqlite3_vfs *pNext; /* Next registered VFS */ 1418 const char *zName; /* Name of this virtual file system */ 1419 void *pAppData; /* Pointer to application-specific data */ 1420 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 1421 int flags, int *pOutFlags); 1422 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1423 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1424 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1425 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1426 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1427 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1428 void (*xDlClose)(sqlite3_vfs*, void*); 1429 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1430 int (*xSleep)(sqlite3_vfs*, int microseconds); 1431 int (*xCurrentTime)(sqlite3_vfs*, double*); 1432 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1433 /* 1434 ** The methods above are in version 1 of the sqlite_vfs object 1435 ** definition. Those that follow are added in version 2 or later 1436 */ 1437 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1438 /* 1439 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1440 ** Those below are for version 3 and greater. 1441 */ 1442 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1443 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1444 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1445 /* 1446 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1447 ** New fields may be appended in future versions. The iVersion 1448 ** value will increment whenever this happens. 1449 */ 1450}; 1451 1452/* 1453** CAPI3REF: Flags for the xAccess VFS method 1454** 1455** These integer constants can be used as the third parameter to 1456** the xAccess method of an [sqlite3_vfs] object. They determine 1457** what kind of permissions the xAccess method is looking for. 1458** With SQLITE_ACCESS_EXISTS, the xAccess method 1459** simply checks whether the file exists. 1460** With SQLITE_ACCESS_READWRITE, the xAccess method 1461** checks whether the named directory is both readable and writable 1462** (in other words, if files can be added, removed, and renamed within 1463** the directory). 1464** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1465** [temp_store_directory pragma], though this could change in a future 1466** release of SQLite. 1467** With SQLITE_ACCESS_READ, the xAccess method 1468** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1469** currently unused, though it might be used in a future release of 1470** SQLite. 1471*/ 1472#define SQLITE_ACCESS_EXISTS 0 1473#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1474#define SQLITE_ACCESS_READ 2 /* Unused */ 1475 1476/* 1477** CAPI3REF: Flags for the xShmLock VFS method 1478** 1479** These integer constants define the various locking operations 1480** allowed by the xShmLock method of [sqlite3_io_methods]. The 1481** following are the only legal combinations of flags to the 1482** xShmLock method: 1483** 1484** <ul> 1485** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1486** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1487** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1488** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1489** </ul> 1490** 1491** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1492** was given on the corresponding lock. 1493** 1494** The xShmLock method can transition between unlocked and SHARED or 1495** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1496** and EXCLUSIVE. 1497*/ 1498#define SQLITE_SHM_UNLOCK 1 1499#define SQLITE_SHM_LOCK 2 1500#define SQLITE_SHM_SHARED 4 1501#define SQLITE_SHM_EXCLUSIVE 8 1502 1503/* 1504** CAPI3REF: Maximum xShmLock index 1505** 1506** The xShmLock method on [sqlite3_io_methods] may use values 1507** between 0 and this upper bound as its "offset" argument. 1508** The SQLite core will never attempt to acquire or release a 1509** lock outside of this range 1510*/ 1511#define SQLITE_SHM_NLOCK 8 1512 1513 1514/* 1515** CAPI3REF: Initialize The SQLite Library 1516** 1517** ^The sqlite3_initialize() routine initializes the 1518** SQLite library. ^The sqlite3_shutdown() routine 1519** deallocates any resources that were allocated by sqlite3_initialize(). 1520** These routines are designed to aid in process initialization and 1521** shutdown on embedded systems. Workstation applications using 1522** SQLite normally do not need to invoke either of these routines. 1523** 1524** A call to sqlite3_initialize() is an "effective" call if it is 1525** the first time sqlite3_initialize() is invoked during the lifetime of 1526** the process, or if it is the first time sqlite3_initialize() is invoked 1527** following a call to sqlite3_shutdown(). ^(Only an effective call 1528** of sqlite3_initialize() does any initialization. All other calls 1529** are harmless no-ops.)^ 1530** 1531** A call to sqlite3_shutdown() is an "effective" call if it is the first 1532** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1533** an effective call to sqlite3_shutdown() does any deinitialization. 1534** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1535** 1536** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1537** is not. The sqlite3_shutdown() interface must only be called from a 1538** single thread. All open [database connections] must be closed and all 1539** other SQLite resources must be deallocated prior to invoking 1540** sqlite3_shutdown(). 1541** 1542** Among other things, ^sqlite3_initialize() will invoke 1543** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1544** will invoke sqlite3_os_end(). 1545** 1546** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1547** ^If for some reason, sqlite3_initialize() is unable to initialize 1548** the library (perhaps it is unable to allocate a needed resource such 1549** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1550** 1551** ^The sqlite3_initialize() routine is called internally by many other 1552** SQLite interfaces so that an application usually does not need to 1553** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1554** calls sqlite3_initialize() so the SQLite library will be automatically 1555** initialized when [sqlite3_open()] is called if it has not be initialized 1556** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1557** compile-time option, then the automatic calls to sqlite3_initialize() 1558** are omitted and the application must call sqlite3_initialize() directly 1559** prior to using any other SQLite interface. For maximum portability, 1560** it is recommended that applications always invoke sqlite3_initialize() 1561** directly prior to using any other SQLite interface. Future releases 1562** of SQLite may require this. In other words, the behavior exhibited 1563** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1564** default behavior in some future release of SQLite. 1565** 1566** The sqlite3_os_init() routine does operating-system specific 1567** initialization of the SQLite library. The sqlite3_os_end() 1568** routine undoes the effect of sqlite3_os_init(). Typical tasks 1569** performed by these routines include allocation or deallocation 1570** of static resources, initialization of global variables, 1571** setting up a default [sqlite3_vfs] module, or setting up 1572** a default configuration using [sqlite3_config()]. 1573** 1574** The application should never invoke either sqlite3_os_init() 1575** or sqlite3_os_end() directly. The application should only invoke 1576** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1577** interface is called automatically by sqlite3_initialize() and 1578** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1579** implementations for sqlite3_os_init() and sqlite3_os_end() 1580** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1581** When [custom builds | built for other platforms] 1582** (using the [SQLITE_OS_OTHER=1] compile-time 1583** option) the application must supply a suitable implementation for 1584** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1585** implementation of sqlite3_os_init() or sqlite3_os_end() 1586** must return [SQLITE_OK] on success and some other [error code] upon 1587** failure. 1588*/ 1589int sqlite3_initialize(void); 1590int sqlite3_shutdown(void); 1591int sqlite3_os_init(void); 1592int sqlite3_os_end(void); 1593 1594/* 1595** CAPI3REF: Configuring The SQLite Library 1596** 1597** The sqlite3_config() interface is used to make global configuration 1598** changes to SQLite in order to tune SQLite to the specific needs of 1599** the application. The default configuration is recommended for most 1600** applications and so this routine is usually not necessary. It is 1601** provided to support rare applications with unusual needs. 1602** 1603** <b>The sqlite3_config() interface is not threadsafe. The application 1604** must ensure that no other SQLite interfaces are invoked by other 1605** threads while sqlite3_config() is running.</b> 1606** 1607** The sqlite3_config() interface 1608** may only be invoked prior to library initialization using 1609** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1610** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1611** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1612** Note, however, that ^sqlite3_config() can be called as part of the 1613** implementation of an application-defined [sqlite3_os_init()]. 1614** 1615** The first argument to sqlite3_config() is an integer 1616** [configuration option] that determines 1617** what property of SQLite is to be configured. Subsequent arguments 1618** vary depending on the [configuration option] 1619** in the first argument. 1620** 1621** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1622** ^If the option is unknown or SQLite is unable to set the option 1623** then this routine returns a non-zero [error code]. 1624*/ 1625int sqlite3_config(int, ...); 1626 1627/* 1628** CAPI3REF: Configure database connections 1629** METHOD: sqlite3 1630** 1631** The sqlite3_db_config() interface is used to make configuration 1632** changes to a [database connection]. The interface is similar to 1633** [sqlite3_config()] except that the changes apply to a single 1634** [database connection] (specified in the first argument). 1635** 1636** The second argument to sqlite3_db_config(D,V,...) is the 1637** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1638** that indicates what aspect of the [database connection] is being configured. 1639** Subsequent arguments vary depending on the configuration verb. 1640** 1641** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1642** the call is considered successful. 1643*/ 1644int sqlite3_db_config(sqlite3*, int op, ...); 1645 1646/* 1647** CAPI3REF: Memory Allocation Routines 1648** 1649** An instance of this object defines the interface between SQLite 1650** and low-level memory allocation routines. 1651** 1652** This object is used in only one place in the SQLite interface. 1653** A pointer to an instance of this object is the argument to 1654** [sqlite3_config()] when the configuration option is 1655** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1656** By creating an instance of this object 1657** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1658** during configuration, an application can specify an alternative 1659** memory allocation subsystem for SQLite to use for all of its 1660** dynamic memory needs. 1661** 1662** Note that SQLite comes with several [built-in memory allocators] 1663** that are perfectly adequate for the overwhelming majority of applications 1664** and that this object is only useful to a tiny minority of applications 1665** with specialized memory allocation requirements. This object is 1666** also used during testing of SQLite in order to specify an alternative 1667** memory allocator that simulates memory out-of-memory conditions in 1668** order to verify that SQLite recovers gracefully from such 1669** conditions. 1670** 1671** The xMalloc, xRealloc, and xFree methods must work like the 1672** malloc(), realloc() and free() functions from the standard C library. 1673** ^SQLite guarantees that the second argument to 1674** xRealloc is always a value returned by a prior call to xRoundup. 1675** 1676** xSize should return the allocated size of a memory allocation 1677** previously obtained from xMalloc or xRealloc. The allocated size 1678** is always at least as big as the requested size but may be larger. 1679** 1680** The xRoundup method returns what would be the allocated size of 1681** a memory allocation given a particular requested size. Most memory 1682** allocators round up memory allocations at least to the next multiple 1683** of 8. Some allocators round up to a larger multiple or to a power of 2. 1684** Every memory allocation request coming in through [sqlite3_malloc()] 1685** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1686** that causes the corresponding memory allocation to fail. 1687** 1688** The xInit method initializes the memory allocator. For example, 1689** it might allocate any required mutexes or initialize internal data 1690** structures. The xShutdown method is invoked (indirectly) by 1691** [sqlite3_shutdown()] and should deallocate any resources acquired 1692** by xInit. The pAppData pointer is used as the only parameter to 1693** xInit and xShutdown. 1694** 1695** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1696** the xInit method, so the xInit method need not be threadsafe. The 1697** xShutdown method is only called from [sqlite3_shutdown()] so it does 1698** not need to be threadsafe either. For all other methods, SQLite 1699** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1700** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1701** it is by default) and so the methods are automatically serialized. 1702** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1703** methods must be threadsafe or else make their own arrangements for 1704** serialization. 1705** 1706** SQLite will never invoke xInit() more than once without an intervening 1707** call to xShutdown(). 1708*/ 1709typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1710struct sqlite3_mem_methods { 1711 void *(*xMalloc)(int); /* Memory allocation function */ 1712 void (*xFree)(void*); /* Free a prior allocation */ 1713 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1714 int (*xSize)(void*); /* Return the size of an allocation */ 1715 int (*xRoundup)(int); /* Round up request size to allocation size */ 1716 int (*xInit)(void*); /* Initialize the memory allocator */ 1717 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1718 void *pAppData; /* Argument to xInit() and xShutdown() */ 1719}; 1720 1721/* 1722** CAPI3REF: Configuration Options 1723** KEYWORDS: {configuration option} 1724** 1725** These constants are the available integer configuration options that 1726** can be passed as the first argument to the [sqlite3_config()] interface. 1727** 1728** New configuration options may be added in future releases of SQLite. 1729** Existing configuration options might be discontinued. Applications 1730** should check the return code from [sqlite3_config()] to make sure that 1731** the call worked. The [sqlite3_config()] interface will return a 1732** non-zero [error code] if a discontinued or unsupported configuration option 1733** is invoked. 1734** 1735** <dl> 1736** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1737** <dd>There are no arguments to this option. ^This option sets the 1738** [threading mode] to Single-thread. In other words, it disables 1739** all mutexing and puts SQLite into a mode where it can only be used 1740** by a single thread. ^If SQLite is compiled with 1741** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1742** it is not possible to change the [threading mode] from its default 1743** value of Single-thread and so [sqlite3_config()] will return 1744** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1745** configuration option.</dd> 1746** 1747** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1748** <dd>There are no arguments to this option. ^This option sets the 1749** [threading mode] to Multi-thread. In other words, it disables 1750** mutexing on [database connection] and [prepared statement] objects. 1751** The application is responsible for serializing access to 1752** [database connections] and [prepared statements]. But other mutexes 1753** are enabled so that SQLite will be safe to use in a multi-threaded 1754** environment as long as no two threads attempt to use the same 1755** [database connection] at the same time. ^If SQLite is compiled with 1756** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1757** it is not possible to set the Multi-thread [threading mode] and 1758** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1759** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1760** 1761** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1762** <dd>There are no arguments to this option. ^This option sets the 1763** [threading mode] to Serialized. In other words, this option enables 1764** all mutexes including the recursive 1765** mutexes on [database connection] and [prepared statement] objects. 1766** In this mode (which is the default when SQLite is compiled with 1767** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1768** to [database connections] and [prepared statements] so that the 1769** application is free to use the same [database connection] or the 1770** same [prepared statement] in different threads at the same time. 1771** ^If SQLite is compiled with 1772** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1773** it is not possible to set the Serialized [threading mode] and 1774** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1775** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1776** 1777** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1778** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1779** a pointer to an instance of the [sqlite3_mem_methods] structure. 1780** The argument specifies 1781** alternative low-level memory allocation routines to be used in place of 1782** the memory allocation routines built into SQLite.)^ ^SQLite makes 1783** its own private copy of the content of the [sqlite3_mem_methods] structure 1784** before the [sqlite3_config()] call returns.</dd> 1785** 1786** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1787** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1788** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1789** The [sqlite3_mem_methods] 1790** structure is filled with the currently defined memory allocation routines.)^ 1791** This option can be used to overload the default memory allocation 1792** routines with a wrapper that simulations memory allocation failure or 1793** tracks memory usage, for example. </dd> 1794** 1795** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1796** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1797** type int, interpreted as a boolean, which if true provides a hint to 1798** SQLite that it should avoid large memory allocations if possible. 1799** SQLite will run faster if it is free to make large memory allocations, 1800** but some application might prefer to run slower in exchange for 1801** guarantees about memory fragmentation that are possible if large 1802** allocations are avoided. This hint is normally off. 1803** </dd> 1804** 1805** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1806** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1807** interpreted as a boolean, which enables or disables the collection of 1808** memory allocation statistics. ^(When memory allocation statistics are 1809** disabled, the following SQLite interfaces become non-operational: 1810** <ul> 1811** <li> [sqlite3_hard_heap_limit64()] 1812** <li> [sqlite3_memory_used()] 1813** <li> [sqlite3_memory_highwater()] 1814** <li> [sqlite3_soft_heap_limit64()] 1815** <li> [sqlite3_status64()] 1816** </ul>)^ 1817** ^Memory allocation statistics are enabled by default unless SQLite is 1818** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1819** allocation statistics are disabled by default. 1820** </dd> 1821** 1822** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1823** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1824** </dd> 1825** 1826** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1827** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1828** that SQLite can use for the database page cache with the default page 1829** cache implementation. 1830** This configuration option is a no-op if an application-defined page 1831** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1832** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1833** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1834** and the number of cache lines (N). 1835** The sz argument should be the size of the largest database page 1836** (a power of two between 512 and 65536) plus some extra bytes for each 1837** page header. ^The number of extra bytes needed by the page header 1838** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1839** ^It is harmless, apart from the wasted memory, 1840** for the sz parameter to be larger than necessary. The pMem 1841** argument must be either a NULL pointer or a pointer to an 8-byte 1842** aligned block of memory of at least sz*N bytes, otherwise 1843** subsequent behavior is undefined. 1844** ^When pMem is not NULL, SQLite will strive to use the memory provided 1845** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1846** a page cache line is larger than sz bytes or if all of the pMem buffer 1847** is exhausted. 1848** ^If pMem is NULL and N is non-zero, then each database connection 1849** does an initial bulk allocation for page cache memory 1850** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1851** of -1024*N bytes if N is negative, . ^If additional 1852** page cache memory is needed beyond what is provided by the initial 1853** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1854** additional cache line. </dd> 1855** 1856** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1857** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1858** that SQLite will use for all of its dynamic memory allocation needs 1859** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1860** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1861** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1862** [SQLITE_ERROR] if invoked otherwise. 1863** ^There are three arguments to SQLITE_CONFIG_HEAP: 1864** An 8-byte aligned pointer to the memory, 1865** the number of bytes in the memory buffer, and the minimum allocation size. 1866** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1867** to using its default memory allocator (the system malloc() implementation), 1868** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1869** memory pointer is not NULL then the alternative memory 1870** allocator is engaged to handle all of SQLites memory allocation needs. 1871** The first pointer (the memory pointer) must be aligned to an 8-byte 1872** boundary or subsequent behavior of SQLite will be undefined. 1873** The minimum allocation size is capped at 2**12. Reasonable values 1874** for the minimum allocation size are 2**5 through 2**8.</dd> 1875** 1876** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1877** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1878** pointer to an instance of the [sqlite3_mutex_methods] structure. 1879** The argument specifies alternative low-level mutex routines to be used 1880** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1881** the content of the [sqlite3_mutex_methods] structure before the call to 1882** [sqlite3_config()] returns. ^If SQLite is compiled with 1883** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1884** the entire mutexing subsystem is omitted from the build and hence calls to 1885** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1886** return [SQLITE_ERROR].</dd> 1887** 1888** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1889** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1890** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1891** [sqlite3_mutex_methods] 1892** structure is filled with the currently defined mutex routines.)^ 1893** This option can be used to overload the default mutex allocation 1894** routines with a wrapper used to track mutex usage for performance 1895** profiling or testing, for example. ^If SQLite is compiled with 1896** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1897** the entire mutexing subsystem is omitted from the build and hence calls to 1898** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1899** return [SQLITE_ERROR].</dd> 1900** 1901** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1902** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1903** the default size of lookaside memory on each [database connection]. 1904** The first argument is the 1905** size of each lookaside buffer slot and the second is the number of 1906** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1907** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1908** option to [sqlite3_db_config()] can be used to change the lookaside 1909** configuration on individual connections.)^ </dd> 1910** 1911** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1912** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1913** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1914** the interface to a custom page cache implementation.)^ 1915** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1916** 1917** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1918** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1919** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1920** the current page cache implementation into that object.)^ </dd> 1921** 1922** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1923** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1924** global [error log]. 1925** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1926** function with a call signature of void(*)(void*,int,const char*), 1927** and a pointer to void. ^If the function pointer is not NULL, it is 1928** invoked by [sqlite3_log()] to process each logging event. ^If the 1929** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1930** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1931** passed through as the first parameter to the application-defined logger 1932** function whenever that function is invoked. ^The second parameter to 1933** the logger function is a copy of the first parameter to the corresponding 1934** [sqlite3_log()] call and is intended to be a [result code] or an 1935** [extended result code]. ^The third parameter passed to the logger is 1936** log message after formatting via [sqlite3_snprintf()]. 1937** The SQLite logging interface is not reentrant; the logger function 1938** supplied by the application must not invoke any SQLite interface. 1939** In a multi-threaded application, the application-defined logger 1940** function must be threadsafe. </dd> 1941** 1942** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1943** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1944** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1945** then URI handling is globally disabled.)^ ^If URI handling is globally 1946** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1947** [sqlite3_open16()] or 1948** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1949** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1950** connection is opened. ^If it is globally disabled, filenames are 1951** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1952** database connection is opened. ^(By default, URI handling is globally 1953** disabled. The default value may be changed by compiling with the 1954** [SQLITE_USE_URI] symbol defined.)^ 1955** 1956** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 1957** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 1958** argument which is interpreted as a boolean in order to enable or disable 1959** the use of covering indices for full table scans in the query optimizer. 1960** ^The default setting is determined 1961** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 1962** if that compile-time option is omitted. 1963** The ability to disable the use of covering indices for full table scans 1964** is because some incorrectly coded legacy applications might malfunction 1965** when the optimization is enabled. Providing the ability to 1966** disable the optimization allows the older, buggy application code to work 1967** without change even with newer versions of SQLite. 1968** 1969** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 1970** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 1971** <dd> These options are obsolete and should not be used by new code. 1972** They are retained for backwards compatibility but are now no-ops. 1973** </dd> 1974** 1975** [[SQLITE_CONFIG_SQLLOG]] 1976** <dt>SQLITE_CONFIG_SQLLOG 1977** <dd>This option is only available if sqlite is compiled with the 1978** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 1979** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 1980** The second should be of type (void*). The callback is invoked by the library 1981** in three separate circumstances, identified by the value passed as the 1982** fourth parameter. If the fourth parameter is 0, then the database connection 1983** passed as the second argument has just been opened. The third argument 1984** points to a buffer containing the name of the main database file. If the 1985** fourth parameter is 1, then the SQL statement that the third parameter 1986** points to has just been executed. Or, if the fourth parameter is 2, then 1987** the connection being passed as the second parameter is being closed. The 1988** third parameter is passed NULL In this case. An example of using this 1989** configuration option can be seen in the "test_sqllog.c" source file in 1990** the canonical SQLite source tree.</dd> 1991** 1992** [[SQLITE_CONFIG_MMAP_SIZE]] 1993** <dt>SQLITE_CONFIG_MMAP_SIZE 1994** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 1995** that are the default mmap size limit (the default setting for 1996** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 1997** ^The default setting can be overridden by each database connection using 1998** either the [PRAGMA mmap_size] command, or by using the 1999** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 2000** will be silently truncated if necessary so that it does not exceed the 2001** compile-time maximum mmap size set by the 2002** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 2003** ^If either argument to this option is negative, then that argument is 2004** changed to its compile-time default. 2005** 2006** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 2007** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 2008** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 2009** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 2010** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 2011** that specifies the maximum size of the created heap. 2012** 2013** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 2014** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 2015** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 2016** is a pointer to an integer and writes into that integer the number of extra 2017** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 2018** The amount of extra space required can change depending on the compiler, 2019** target platform, and SQLite version. 2020** 2021** [[SQLITE_CONFIG_PMASZ]] 2022** <dt>SQLITE_CONFIG_PMASZ 2023** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 2024** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 2025** sorter to that integer. The default minimum PMA Size is set by the 2026** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 2027** to help with sort operations when multithreaded sorting 2028** is enabled (using the [PRAGMA threads] command) and the amount of content 2029** to be sorted exceeds the page size times the minimum of the 2030** [PRAGMA cache_size] setting and this value. 2031** 2032** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 2033** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 2034** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 2035** becomes the [statement journal] spill-to-disk threshold. 2036** [Statement journals] are held in memory until their size (in bytes) 2037** exceeds this threshold, at which point they are written to disk. 2038** Or if the threshold is -1, statement journals are always held 2039** exclusively in memory. 2040** Since many statement journals never become large, setting the spill 2041** threshold to a value such as 64KiB can greatly reduce the amount of 2042** I/O required to support statement rollback. 2043** The default value for this setting is controlled by the 2044** [SQLITE_STMTJRNL_SPILL] compile-time option. 2045** 2046** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2047** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2048** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2049** of type (int) - the new value of the sorter-reference size threshold. 2050** Usually, when SQLite uses an external sort to order records according 2051** to an ORDER BY clause, all fields required by the caller are present in the 2052** sorted records. However, if SQLite determines based on the declared type 2053** of a table column that its values are likely to be very large - larger 2054** than the configured sorter-reference size threshold - then a reference 2055** is stored in each sorted record and the required column values loaded 2056** from the database as records are returned in sorted order. The default 2057** value for this option is to never use this optimization. Specifying a 2058** negative value for this option restores the default behaviour. 2059** This option is only available if SQLite is compiled with the 2060** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2061** 2062** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2063** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2064** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2065** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2066** database created using [sqlite3_deserialize()]. This default maximum 2067** size can be adjusted up or down for individual databases using the 2068** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2069** configuration setting is never used, then the default maximum is determined 2070** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2071** compile-time option is not set, then the default maximum is 1073741824. 2072** </dl> 2073*/ 2074#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2075#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2076#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2077#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2078#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2079#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2080#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2081#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2082#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2083#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2084#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2085/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2086#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2087#define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2088#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2089#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2090#define SQLITE_CONFIG_URI 17 /* int */ 2091#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2092#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2093#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2094#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2095#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2096#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2097#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2098#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2099#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2100#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2101#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2102#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2103 2104/* 2105** CAPI3REF: Database Connection Configuration Options 2106** 2107** These constants are the available integer configuration options that 2108** can be passed as the second argument to the [sqlite3_db_config()] interface. 2109** 2110** New configuration options may be added in future releases of SQLite. 2111** Existing configuration options might be discontinued. Applications 2112** should check the return code from [sqlite3_db_config()] to make sure that 2113** the call worked. ^The [sqlite3_db_config()] interface will return a 2114** non-zero [error code] if a discontinued or unsupported configuration option 2115** is invoked. 2116** 2117** <dl> 2118** [[SQLITE_DBCONFIG_LOOKASIDE]] 2119** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2120** <dd> ^This option takes three additional arguments that determine the 2121** [lookaside memory allocator] configuration for the [database connection]. 2122** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2123** pointer to a memory buffer to use for lookaside memory. 2124** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2125** may be NULL in which case SQLite will allocate the 2126** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2127** size of each lookaside buffer slot. ^The third argument is the number of 2128** slots. The size of the buffer in the first argument must be greater than 2129** or equal to the product of the second and third arguments. The buffer 2130** must be aligned to an 8-byte boundary. ^If the second argument to 2131** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2132** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2133** configuration for a database connection can only be changed when that 2134** connection is not currently using lookaside memory, or in other words 2135** when the "current value" returned by 2136** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 2137** Any attempt to change the lookaside memory configuration when lookaside 2138** memory is in use leaves the configuration unchanged and returns 2139** [SQLITE_BUSY].)^</dd> 2140** 2141** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2142** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2143** <dd> ^This option is used to enable or disable the enforcement of 2144** [foreign key constraints]. There should be two additional arguments. 2145** The first argument is an integer which is 0 to disable FK enforcement, 2146** positive to enable FK enforcement or negative to leave FK enforcement 2147** unchanged. The second parameter is a pointer to an integer into which 2148** is written 0 or 1 to indicate whether FK enforcement is off or on 2149** following this call. The second parameter may be a NULL pointer, in 2150** which case the FK enforcement setting is not reported back. </dd> 2151** 2152** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2153** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2154** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2155** There should be two additional arguments. 2156** The first argument is an integer which is 0 to disable triggers, 2157** positive to enable triggers or negative to leave the setting unchanged. 2158** The second parameter is a pointer to an integer into which 2159** is written 0 or 1 to indicate whether triggers are disabled or enabled 2160** following this call. The second parameter may be a NULL pointer, in 2161** which case the trigger setting is not reported back. 2162** 2163** <p>Originally this option disabled all triggers. ^(However, since 2164** SQLite version 3.35.0, TEMP triggers are still allowed even if 2165** this option is off. So, in other words, this option now only disables 2166** triggers in the main database schema or in the schemas of ATTACH-ed 2167** databases.)^ </dd> 2168** 2169** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2170** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2171** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2172** There should be two additional arguments. 2173** The first argument is an integer which is 0 to disable views, 2174** positive to enable views or negative to leave the setting unchanged. 2175** The second parameter is a pointer to an integer into which 2176** is written 0 or 1 to indicate whether views are disabled or enabled 2177** following this call. The second parameter may be a NULL pointer, in 2178** which case the view setting is not reported back. 2179** 2180** <p>Originally this option disabled all views. ^(However, since 2181** SQLite version 3.35.0, TEMP views are still allowed even if 2182** this option is off. So, in other words, this option now only disables 2183** views in the main database schema or in the schemas of ATTACH-ed 2184** databases.)^ </dd> 2185** 2186** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2187** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2188** <dd> ^This option is used to enable or disable the 2189** [fts3_tokenizer()] function which is part of the 2190** [FTS3] full-text search engine extension. 2191** There should be two additional arguments. 2192** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2193** positive to enable fts3_tokenizer() or negative to leave the setting 2194** unchanged. 2195** The second parameter is a pointer to an integer into which 2196** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2197** following this call. The second parameter may be a NULL pointer, in 2198** which case the new setting is not reported back. </dd> 2199** 2200** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2201** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2202** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2203** interface independently of the [load_extension()] SQL function. 2204** The [sqlite3_enable_load_extension()] API enables or disables both the 2205** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2206** There should be two additional arguments. 2207** When the first argument to this interface is 1, then only the C-API is 2208** enabled and the SQL function remains disabled. If the first argument to 2209** this interface is 0, then both the C-API and the SQL function are disabled. 2210** If the first argument is -1, then no changes are made to state of either the 2211** C-API or the SQL function. 2212** The second parameter is a pointer to an integer into which 2213** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2214** is disabled or enabled following this call. The second parameter may 2215** be a NULL pointer, in which case the new setting is not reported back. 2216** </dd> 2217** 2218** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2219** <dd> ^This option is used to change the name of the "main" database 2220** schema. ^The sole argument is a pointer to a constant UTF8 string 2221** which will become the new schema name in place of "main". ^SQLite 2222** does not make a copy of the new main schema name string, so the application 2223** must ensure that the argument passed into this DBCONFIG option is unchanged 2224** until after the database connection closes. 2225** </dd> 2226** 2227** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2228** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2229** <dd> Usually, when a database in wal mode is closed or detached from a 2230** database handle, SQLite checks if this will mean that there are now no 2231** connections at all to the database. If so, it performs a checkpoint 2232** operation before closing the connection. This option may be used to 2233** override this behaviour. The first parameter passed to this operation 2234** is an integer - positive to disable checkpoints-on-close, or zero (the 2235** default) to enable them, and negative to leave the setting unchanged. 2236** The second parameter is a pointer to an integer 2237** into which is written 0 or 1 to indicate whether checkpoints-on-close 2238** have been disabled - 0 if they are not disabled, 1 if they are. 2239** </dd> 2240** 2241** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2242** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2243** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2244** a single SQL query statement will always use the same algorithm regardless 2245** of values of [bound parameters].)^ The QPSG disables some query optimizations 2246** that look at the values of bound parameters, which can make some queries 2247** slower. But the QPSG has the advantage of more predictable behavior. With 2248** the QPSG active, SQLite will always use the same query plan in the field as 2249** was used during testing in the lab. 2250** The first argument to this setting is an integer which is 0 to disable 2251** the QPSG, positive to enable QPSG, or negative to leave the setting 2252** unchanged. The second parameter is a pointer to an integer into which 2253** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2254** following this call. 2255** </dd> 2256** 2257** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2258** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2259** include output for any operations performed by trigger programs. This 2260** option is used to set or clear (the default) a flag that governs this 2261** behavior. The first parameter passed to this operation is an integer - 2262** positive to enable output for trigger programs, or zero to disable it, 2263** or negative to leave the setting unchanged. 2264** The second parameter is a pointer to an integer into which is written 2265** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2266** it is not disabled, 1 if it is. 2267** </dd> 2268** 2269** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2270** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2271** [VACUUM] in order to reset a database back to an empty database 2272** with no schema and no content. The following process works even for 2273** a badly corrupted database file: 2274** <ol> 2275** <li> If the database connection is newly opened, make sure it has read the 2276** database schema by preparing then discarding some query against the 2277** database, or calling sqlite3_table_column_metadata(), ignoring any 2278** errors. This step is only necessary if the application desires to keep 2279** the database in WAL mode after the reset if it was in WAL mode before 2280** the reset. 2281** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2282** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2283** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2284** </ol> 2285** Because resetting a database is destructive and irreversible, the 2286** process requires the use of this obscure API and multiple steps to help 2287** ensure that it does not happen by accident. 2288** 2289** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2290** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2291** "defensive" flag for a database connection. When the defensive 2292** flag is enabled, language features that allow ordinary SQL to 2293** deliberately corrupt the database file are disabled. The disabled 2294** features include but are not limited to the following: 2295** <ul> 2296** <li> The [PRAGMA writable_schema=ON] statement. 2297** <li> The [PRAGMA journal_mode=OFF] statement. 2298** <li> Writes to the [sqlite_dbpage] virtual table. 2299** <li> Direct writes to [shadow tables]. 2300** </ul> 2301** </dd> 2302** 2303** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2304** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2305** "writable_schema" flag. This has the same effect and is logically equivalent 2306** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2307** The first argument to this setting is an integer which is 0 to disable 2308** the writable_schema, positive to enable writable_schema, or negative to 2309** leave the setting unchanged. The second parameter is a pointer to an 2310** integer into which is written 0 or 1 to indicate whether the writable_schema 2311** is enabled or disabled following this call. 2312** </dd> 2313** 2314** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2315** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2316** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2317** the legacy behavior of the [ALTER TABLE RENAME] command such it 2318** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2319** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2320** additional information. This feature can also be turned on and off 2321** using the [PRAGMA legacy_alter_table] statement. 2322** </dd> 2323** 2324** [[SQLITE_DBCONFIG_DQS_DML]] 2325** <dt>SQLITE_DBCONFIG_DQS_DML</td> 2326** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2327** the legacy [double-quoted string literal] misfeature for DML statements 2328** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2329** default value of this setting is determined by the [-DSQLITE_DQS] 2330** compile-time option. 2331** </dd> 2332** 2333** [[SQLITE_DBCONFIG_DQS_DDL]] 2334** <dt>SQLITE_DBCONFIG_DQS_DDL</td> 2335** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2336** the legacy [double-quoted string literal] misfeature for DDL statements, 2337** such as CREATE TABLE and CREATE INDEX. The 2338** default value of this setting is determined by the [-DSQLITE_DQS] 2339** compile-time option. 2340** </dd> 2341** 2342** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2343** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> 2344** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2345** assume that database schemas are untainted by malicious content. 2346** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2347** takes additional defensive steps to protect the application from harm 2348** including: 2349** <ul> 2350** <li> Prohibit the use of SQL functions inside triggers, views, 2351** CHECK constraints, DEFAULT clauses, expression indexes, 2352** partial indexes, or generated columns 2353** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2354** <li> Prohibit the use of virtual tables inside of triggers or views 2355** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2356** </ul> 2357** This setting defaults to "on" for legacy compatibility, however 2358** all applications are advised to turn it off if possible. This setting 2359** can also be controlled using the [PRAGMA trusted_schema] statement. 2360** </dd> 2361** 2362** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2363** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> 2364** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2365** the legacy file format flag. When activated, this flag causes all newly 2366** created database file to have a schema format version number (the 4-byte 2367** integer found at offset 44 into the database header) of 1. This in turn 2368** means that the resulting database file will be readable and writable by 2369** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2370** newly created databases are generally not understandable by SQLite versions 2371** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2372** is now scarcely any need to generated database files that are compatible 2373** all the way back to version 3.0.0, and so this setting is of little 2374** practical use, but is provided so that SQLite can continue to claim the 2375** ability to generate new database files that are compatible with version 2376** 3.0.0. 2377** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2378** the [VACUUM] command will fail with an obscure error when attempting to 2379** process a table with generated columns and a descending index. This is 2380** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2381** either generated columns or decending indexes. 2382** </dd> 2383** </dl> 2384*/ 2385#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2386#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2387#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2388#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2389#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2390#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2391#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2392#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2393#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2394#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2395#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2396#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2397#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2398#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2399#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2400#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2401#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2402#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2403#define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ 2404 2405/* 2406** CAPI3REF: Enable Or Disable Extended Result Codes 2407** METHOD: sqlite3 2408** 2409** ^The sqlite3_extended_result_codes() routine enables or disables the 2410** [extended result codes] feature of SQLite. ^The extended result 2411** codes are disabled by default for historical compatibility. 2412*/ 2413int sqlite3_extended_result_codes(sqlite3*, int onoff); 2414 2415/* 2416** CAPI3REF: Last Insert Rowid 2417** METHOD: sqlite3 2418** 2419** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2420** has a unique 64-bit signed 2421** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2422** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2423** names are not also used by explicitly declared columns. ^If 2424** the table has a column of type [INTEGER PRIMARY KEY] then that column 2425** is another alias for the rowid. 2426** 2427** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2428** the most recent successful [INSERT] into a rowid table or [virtual table] 2429** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2430** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2431** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2432** zero. 2433** 2434** As well as being set automatically as rows are inserted into database 2435** tables, the value returned by this function may be set explicitly by 2436** [sqlite3_set_last_insert_rowid()] 2437** 2438** Some virtual table implementations may INSERT rows into rowid tables as 2439** part of committing a transaction (e.g. to flush data accumulated in memory 2440** to disk). In this case subsequent calls to this function return the rowid 2441** associated with these internal INSERT operations, which leads to 2442** unintuitive results. Virtual table implementations that do write to rowid 2443** tables in this way can avoid this problem by restoring the original 2444** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2445** control to the user. 2446** 2447** ^(If an [INSERT] occurs within a trigger then this routine will 2448** return the [rowid] of the inserted row as long as the trigger is 2449** running. Once the trigger program ends, the value returned 2450** by this routine reverts to what it was before the trigger was fired.)^ 2451** 2452** ^An [INSERT] that fails due to a constraint violation is not a 2453** successful [INSERT] and does not change the value returned by this 2454** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2455** and INSERT OR ABORT make no changes to the return value of this 2456** routine when their insertion fails. ^(When INSERT OR REPLACE 2457** encounters a constraint violation, it does not fail. The 2458** INSERT continues to completion after deleting rows that caused 2459** the constraint problem so INSERT OR REPLACE will always change 2460** the return value of this interface.)^ 2461** 2462** ^For the purposes of this routine, an [INSERT] is considered to 2463** be successful even if it is subsequently rolled back. 2464** 2465** This function is accessible to SQL statements via the 2466** [last_insert_rowid() SQL function]. 2467** 2468** If a separate thread performs a new [INSERT] on the same 2469** database connection while the [sqlite3_last_insert_rowid()] 2470** function is running and thus changes the last insert [rowid], 2471** then the value returned by [sqlite3_last_insert_rowid()] is 2472** unpredictable and might not equal either the old or the new 2473** last insert [rowid]. 2474*/ 2475sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2476 2477/* 2478** CAPI3REF: Set the Last Insert Rowid value. 2479** METHOD: sqlite3 2480** 2481** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2482** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2483** without inserting a row into the database. 2484*/ 2485void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2486 2487/* 2488** CAPI3REF: Count The Number Of Rows Modified 2489** METHOD: sqlite3 2490** 2491** ^These functions return the number of rows modified, inserted or 2492** deleted by the most recently completed INSERT, UPDATE or DELETE 2493** statement on the database connection specified by the only parameter. 2494** The two functions are identical except for the type of the return value 2495** and that if the number of rows modified by the most recent INSERT, UPDATE 2496** or DELETE is greater than the maximum value supported by type "int", then 2497** the return value of sqlite3_changes() is undefined. ^Executing any other 2498** type of SQL statement does not modify the value returned by these functions. 2499** 2500** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2501** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2502** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2503** 2504** Changes to a view that are intercepted by 2505** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2506** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2507** DELETE statement run on a view is always zero. Only changes made to real 2508** tables are counted. 2509** 2510** Things are more complicated if the sqlite3_changes() function is 2511** executed while a trigger program is running. This may happen if the 2512** program uses the [changes() SQL function], or if some other callback 2513** function invokes sqlite3_changes() directly. Essentially: 2514** 2515** <ul> 2516** <li> ^(Before entering a trigger program the value returned by 2517** sqlite3_changes() function is saved. After the trigger program 2518** has finished, the original value is restored.)^ 2519** 2520** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2521** statement sets the value returned by sqlite3_changes() 2522** upon completion as normal. Of course, this value will not include 2523** any changes performed by sub-triggers, as the sqlite3_changes() 2524** value will be saved and restored after each sub-trigger has run.)^ 2525** </ul> 2526** 2527** ^This means that if the changes() SQL function (or similar) is used 2528** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2529** returns the value as set when the calling statement began executing. 2530** ^If it is used by the second or subsequent such statement within a trigger 2531** program, the value returned reflects the number of rows modified by the 2532** previous INSERT, UPDATE or DELETE statement within the same trigger. 2533** 2534** If a separate thread makes changes on the same database connection 2535** while [sqlite3_changes()] is running then the value returned 2536** is unpredictable and not meaningful. 2537** 2538** See also: 2539** <ul> 2540** <li> the [sqlite3_total_changes()] interface 2541** <li> the [count_changes pragma] 2542** <li> the [changes() SQL function] 2543** <li> the [data_version pragma] 2544** </ul> 2545*/ 2546int sqlite3_changes(sqlite3*); 2547sqlite3_int64 sqlite3_changes64(sqlite3*); 2548 2549/* 2550** CAPI3REF: Total Number Of Rows Modified 2551** METHOD: sqlite3 2552** 2553** ^These functions return the total number of rows inserted, modified or 2554** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2555** since the database connection was opened, including those executed as 2556** part of trigger programs. The two functions are identical except for the 2557** type of the return value and that if the number of rows modified by the 2558** connection exceeds the maximum value supported by type "int", then 2559** the return value of sqlite3_total_changes() is undefined. ^Executing 2560** any other type of SQL statement does not affect the value returned by 2561** sqlite3_total_changes(). 2562** 2563** ^Changes made as part of [foreign key actions] are included in the 2564** count, but those made as part of REPLACE constraint resolution are 2565** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2566** are not counted. 2567** 2568** The [sqlite3_total_changes(D)] interface only reports the number 2569** of rows that changed due to SQL statement run against database 2570** connection D. Any changes by other database connections are ignored. 2571** To detect changes against a database file from other database 2572** connections use the [PRAGMA data_version] command or the 2573** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2574** 2575** If a separate thread makes changes on the same database connection 2576** while [sqlite3_total_changes()] is running then the value 2577** returned is unpredictable and not meaningful. 2578** 2579** See also: 2580** <ul> 2581** <li> the [sqlite3_changes()] interface 2582** <li> the [count_changes pragma] 2583** <li> the [changes() SQL function] 2584** <li> the [data_version pragma] 2585** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2586** </ul> 2587*/ 2588int sqlite3_total_changes(sqlite3*); 2589sqlite3_int64 sqlite3_total_changes64(sqlite3*); 2590 2591/* 2592** CAPI3REF: Interrupt A Long-Running Query 2593** METHOD: sqlite3 2594** 2595** ^This function causes any pending database operation to abort and 2596** return at its earliest opportunity. This routine is typically 2597** called in response to a user action such as pressing "Cancel" 2598** or Ctrl-C where the user wants a long query operation to halt 2599** immediately. 2600** 2601** ^It is safe to call this routine from a thread different from the 2602** thread that is currently running the database operation. But it 2603** is not safe to call this routine with a [database connection] that 2604** is closed or might close before sqlite3_interrupt() returns. 2605** 2606** ^If an SQL operation is very nearly finished at the time when 2607** sqlite3_interrupt() is called, then it might not have an opportunity 2608** to be interrupted and might continue to completion. 2609** 2610** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2611** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2612** that is inside an explicit transaction, then the entire transaction 2613** will be rolled back automatically. 2614** 2615** ^The sqlite3_interrupt(D) call is in effect until all currently running 2616** SQL statements on [database connection] D complete. ^Any new SQL statements 2617** that are started after the sqlite3_interrupt() call and before the 2618** running statement count reaches zero are interrupted as if they had been 2619** running prior to the sqlite3_interrupt() call. ^New SQL statements 2620** that are started after the running statement count reaches zero are 2621** not effected by the sqlite3_interrupt(). 2622** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2623** SQL statements is a no-op and has no effect on SQL statements 2624** that are started after the sqlite3_interrupt() call returns. 2625*/ 2626void sqlite3_interrupt(sqlite3*); 2627 2628/* 2629** CAPI3REF: Determine If An SQL Statement Is Complete 2630** 2631** These routines are useful during command-line input to determine if the 2632** currently entered text seems to form a complete SQL statement or 2633** if additional input is needed before sending the text into 2634** SQLite for parsing. ^These routines return 1 if the input string 2635** appears to be a complete SQL statement. ^A statement is judged to be 2636** complete if it ends with a semicolon token and is not a prefix of a 2637** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2638** string literals or quoted identifier names or comments are not 2639** independent tokens (they are part of the token in which they are 2640** embedded) and thus do not count as a statement terminator. ^Whitespace 2641** and comments that follow the final semicolon are ignored. 2642** 2643** ^These routines return 0 if the statement is incomplete. ^If a 2644** memory allocation fails, then SQLITE_NOMEM is returned. 2645** 2646** ^These routines do not parse the SQL statements thus 2647** will not detect syntactically incorrect SQL. 2648** 2649** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2650** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2651** automatically by sqlite3_complete16(). If that initialization fails, 2652** then the return value from sqlite3_complete16() will be non-zero 2653** regardless of whether or not the input SQL is complete.)^ 2654** 2655** The input to [sqlite3_complete()] must be a zero-terminated 2656** UTF-8 string. 2657** 2658** The input to [sqlite3_complete16()] must be a zero-terminated 2659** UTF-16 string in native byte order. 2660*/ 2661int sqlite3_complete(const char *sql); 2662int sqlite3_complete16(const void *sql); 2663 2664/* 2665** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2666** KEYWORDS: {busy-handler callback} {busy handler} 2667** METHOD: sqlite3 2668** 2669** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2670** that might be invoked with argument P whenever 2671** an attempt is made to access a database table associated with 2672** [database connection] D when another thread 2673** or process has the table locked. 2674** The sqlite3_busy_handler() interface is used to implement 2675** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2676** 2677** ^If the busy callback is NULL, then [SQLITE_BUSY] 2678** is returned immediately upon encountering the lock. ^If the busy callback 2679** is not NULL, then the callback might be invoked with two arguments. 2680** 2681** ^The first argument to the busy handler is a copy of the void* pointer which 2682** is the third argument to sqlite3_busy_handler(). ^The second argument to 2683** the busy handler callback is the number of times that the busy handler has 2684** been invoked previously for the same locking event. ^If the 2685** busy callback returns 0, then no additional attempts are made to 2686** access the database and [SQLITE_BUSY] is returned 2687** to the application. 2688** ^If the callback returns non-zero, then another attempt 2689** is made to access the database and the cycle repeats. 2690** 2691** The presence of a busy handler does not guarantee that it will be invoked 2692** when there is lock contention. ^If SQLite determines that invoking the busy 2693** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2694** to the application instead of invoking the 2695** busy handler. 2696** Consider a scenario where one process is holding a read lock that 2697** it is trying to promote to a reserved lock and 2698** a second process is holding a reserved lock that it is trying 2699** to promote to an exclusive lock. The first process cannot proceed 2700** because it is blocked by the second and the second process cannot 2701** proceed because it is blocked by the first. If both processes 2702** invoke the busy handlers, neither will make any progress. Therefore, 2703** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2704** will induce the first process to release its read lock and allow 2705** the second process to proceed. 2706** 2707** ^The default busy callback is NULL. 2708** 2709** ^(There can only be a single busy handler defined for each 2710** [database connection]. Setting a new busy handler clears any 2711** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2712** or evaluating [PRAGMA busy_timeout=N] will change the 2713** busy handler and thus clear any previously set busy handler. 2714** 2715** The busy callback should not take any actions which modify the 2716** database connection that invoked the busy handler. In other words, 2717** the busy handler is not reentrant. Any such actions 2718** result in undefined behavior. 2719** 2720** A busy handler must not close the database connection 2721** or [prepared statement] that invoked the busy handler. 2722*/ 2723int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2724 2725/* 2726** CAPI3REF: Set A Busy Timeout 2727** METHOD: sqlite3 2728** 2729** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2730** for a specified amount of time when a table is locked. ^The handler 2731** will sleep multiple times until at least "ms" milliseconds of sleeping 2732** have accumulated. ^After at least "ms" milliseconds of sleeping, 2733** the handler returns 0 which causes [sqlite3_step()] to return 2734** [SQLITE_BUSY]. 2735** 2736** ^Calling this routine with an argument less than or equal to zero 2737** turns off all busy handlers. 2738** 2739** ^(There can only be a single busy handler for a particular 2740** [database connection] at any given moment. If another busy handler 2741** was defined (using [sqlite3_busy_handler()]) prior to calling 2742** this routine, that other busy handler is cleared.)^ 2743** 2744** See also: [PRAGMA busy_timeout] 2745*/ 2746int sqlite3_busy_timeout(sqlite3*, int ms); 2747 2748/* 2749** CAPI3REF: Convenience Routines For Running Queries 2750** METHOD: sqlite3 2751** 2752** This is a legacy interface that is preserved for backwards compatibility. 2753** Use of this interface is not recommended. 2754** 2755** Definition: A <b>result table</b> is memory data structure created by the 2756** [sqlite3_get_table()] interface. A result table records the 2757** complete query results from one or more queries. 2758** 2759** The table conceptually has a number of rows and columns. But 2760** these numbers are not part of the result table itself. These 2761** numbers are obtained separately. Let N be the number of rows 2762** and M be the number of columns. 2763** 2764** A result table is an array of pointers to zero-terminated UTF-8 strings. 2765** There are (N+1)*M elements in the array. The first M pointers point 2766** to zero-terminated strings that contain the names of the columns. 2767** The remaining entries all point to query results. NULL values result 2768** in NULL pointers. All other values are in their UTF-8 zero-terminated 2769** string representation as returned by [sqlite3_column_text()]. 2770** 2771** A result table might consist of one or more memory allocations. 2772** It is not safe to pass a result table directly to [sqlite3_free()]. 2773** A result table should be deallocated using [sqlite3_free_table()]. 2774** 2775** ^(As an example of the result table format, suppose a query result 2776** is as follows: 2777** 2778** <blockquote><pre> 2779** Name | Age 2780** ----------------------- 2781** Alice | 43 2782** Bob | 28 2783** Cindy | 21 2784** </pre></blockquote> 2785** 2786** There are two columns (M==2) and three rows (N==3). Thus the 2787** result table has 8 entries. Suppose the result table is stored 2788** in an array named azResult. Then azResult holds this content: 2789** 2790** <blockquote><pre> 2791** azResult[0] = "Name"; 2792** azResult[1] = "Age"; 2793** azResult[2] = "Alice"; 2794** azResult[3] = "43"; 2795** azResult[4] = "Bob"; 2796** azResult[5] = "28"; 2797** azResult[6] = "Cindy"; 2798** azResult[7] = "21"; 2799** </pre></blockquote>)^ 2800** 2801** ^The sqlite3_get_table() function evaluates one or more 2802** semicolon-separated SQL statements in the zero-terminated UTF-8 2803** string of its 2nd parameter and returns a result table to the 2804** pointer given in its 3rd parameter. 2805** 2806** After the application has finished with the result from sqlite3_get_table(), 2807** it must pass the result table pointer to sqlite3_free_table() in order to 2808** release the memory that was malloced. Because of the way the 2809** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2810** function must not try to call [sqlite3_free()] directly. Only 2811** [sqlite3_free_table()] is able to release the memory properly and safely. 2812** 2813** The sqlite3_get_table() interface is implemented as a wrapper around 2814** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2815** to any internal data structures of SQLite. It uses only the public 2816** interface defined here. As a consequence, errors that occur in the 2817** wrapper layer outside of the internal [sqlite3_exec()] call are not 2818** reflected in subsequent calls to [sqlite3_errcode()] or 2819** [sqlite3_errmsg()]. 2820*/ 2821int sqlite3_get_table( 2822 sqlite3 *db, /* An open database */ 2823 const char *zSql, /* SQL to be evaluated */ 2824 char ***pazResult, /* Results of the query */ 2825 int *pnRow, /* Number of result rows written here */ 2826 int *pnColumn, /* Number of result columns written here */ 2827 char **pzErrmsg /* Error msg written here */ 2828); 2829void sqlite3_free_table(char **result); 2830 2831/* 2832** CAPI3REF: Formatted String Printing Functions 2833** 2834** These routines are work-alikes of the "printf()" family of functions 2835** from the standard C library. 2836** These routines understand most of the common formatting options from 2837** the standard library printf() 2838** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2839** See the [built-in printf()] documentation for details. 2840** 2841** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2842** results into memory obtained from [sqlite3_malloc64()]. 2843** The strings returned by these two routines should be 2844** released by [sqlite3_free()]. ^Both routines return a 2845** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2846** memory to hold the resulting string. 2847** 2848** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2849** the standard C library. The result is written into the 2850** buffer supplied as the second parameter whose size is given by 2851** the first parameter. Note that the order of the 2852** first two parameters is reversed from snprintf().)^ This is an 2853** historical accident that cannot be fixed without breaking 2854** backwards compatibility. ^(Note also that sqlite3_snprintf() 2855** returns a pointer to its buffer instead of the number of 2856** characters actually written into the buffer.)^ We admit that 2857** the number of characters written would be a more useful return 2858** value but we cannot change the implementation of sqlite3_snprintf() 2859** now without breaking compatibility. 2860** 2861** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2862** guarantees that the buffer is always zero-terminated. ^The first 2863** parameter "n" is the total size of the buffer, including space for 2864** the zero terminator. So the longest string that can be completely 2865** written will be n-1 characters. 2866** 2867** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2868** 2869** See also: [built-in printf()], [printf() SQL function] 2870*/ 2871char *sqlite3_mprintf(const char*,...); 2872char *sqlite3_vmprintf(const char*, va_list); 2873char *sqlite3_snprintf(int,char*,const char*, ...); 2874char *sqlite3_vsnprintf(int,char*,const char*, va_list); 2875 2876/* 2877** CAPI3REF: Memory Allocation Subsystem 2878** 2879** The SQLite core uses these three routines for all of its own 2880** internal memory allocation needs. "Core" in the previous sentence 2881** does not include operating-system specific [VFS] implementation. The 2882** Windows VFS uses native malloc() and free() for some operations. 2883** 2884** ^The sqlite3_malloc() routine returns a pointer to a block 2885** of memory at least N bytes in length, where N is the parameter. 2886** ^If sqlite3_malloc() is unable to obtain sufficient free 2887** memory, it returns a NULL pointer. ^If the parameter N to 2888** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2889** a NULL pointer. 2890** 2891** ^The sqlite3_malloc64(N) routine works just like 2892** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2893** of a signed 32-bit integer. 2894** 2895** ^Calling sqlite3_free() with a pointer previously returned 2896** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2897** that it might be reused. ^The sqlite3_free() routine is 2898** a no-op if is called with a NULL pointer. Passing a NULL pointer 2899** to sqlite3_free() is harmless. After being freed, memory 2900** should neither be read nor written. Even reading previously freed 2901** memory might result in a segmentation fault or other severe error. 2902** Memory corruption, a segmentation fault, or other severe error 2903** might result if sqlite3_free() is called with a non-NULL pointer that 2904** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2905** 2906** ^The sqlite3_realloc(X,N) interface attempts to resize a 2907** prior memory allocation X to be at least N bytes. 2908** ^If the X parameter to sqlite3_realloc(X,N) 2909** is a NULL pointer then its behavior is identical to calling 2910** sqlite3_malloc(N). 2911** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2912** negative then the behavior is exactly the same as calling 2913** sqlite3_free(X). 2914** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2915** of at least N bytes in size or NULL if insufficient memory is available. 2916** ^If M is the size of the prior allocation, then min(N,M) bytes 2917** of the prior allocation are copied into the beginning of buffer returned 2918** by sqlite3_realloc(X,N) and the prior allocation is freed. 2919** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2920** prior allocation is not freed. 2921** 2922** ^The sqlite3_realloc64(X,N) interfaces works the same as 2923** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2924** of a 32-bit signed integer. 2925** 2926** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2927** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2928** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2929** ^The value returned by sqlite3_msize(X) might be larger than the number 2930** of bytes requested when X was allocated. ^If X is a NULL pointer then 2931** sqlite3_msize(X) returns zero. If X points to something that is not 2932** the beginning of memory allocation, or if it points to a formerly 2933** valid memory allocation that has now been freed, then the behavior 2934** of sqlite3_msize(X) is undefined and possibly harmful. 2935** 2936** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2937** sqlite3_malloc64(), and sqlite3_realloc64() 2938** is always aligned to at least an 8 byte boundary, or to a 2939** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2940** option is used. 2941** 2942** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2943** must be either NULL or else pointers obtained from a prior 2944** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2945** not yet been released. 2946** 2947** The application must not read or write any part of 2948** a block of memory after it has been released using 2949** [sqlite3_free()] or [sqlite3_realloc()]. 2950*/ 2951void *sqlite3_malloc(int); 2952void *sqlite3_malloc64(sqlite3_uint64); 2953void *sqlite3_realloc(void*, int); 2954void *sqlite3_realloc64(void*, sqlite3_uint64); 2955void sqlite3_free(void*); 2956sqlite3_uint64 sqlite3_msize(void*); 2957 2958/* 2959** CAPI3REF: Memory Allocator Statistics 2960** 2961** SQLite provides these two interfaces for reporting on the status 2962** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 2963** routines, which form the built-in memory allocation subsystem. 2964** 2965** ^The [sqlite3_memory_used()] routine returns the number of bytes 2966** of memory currently outstanding (malloced but not freed). 2967** ^The [sqlite3_memory_highwater()] routine returns the maximum 2968** value of [sqlite3_memory_used()] since the high-water mark 2969** was last reset. ^The values returned by [sqlite3_memory_used()] and 2970** [sqlite3_memory_highwater()] include any overhead 2971** added by SQLite in its implementation of [sqlite3_malloc()], 2972** but not overhead added by the any underlying system library 2973** routines that [sqlite3_malloc()] may call. 2974** 2975** ^The memory high-water mark is reset to the current value of 2976** [sqlite3_memory_used()] if and only if the parameter to 2977** [sqlite3_memory_highwater()] is true. ^The value returned 2978** by [sqlite3_memory_highwater(1)] is the high-water mark 2979** prior to the reset. 2980*/ 2981sqlite3_int64 sqlite3_memory_used(void); 2982sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 2983 2984/* 2985** CAPI3REF: Pseudo-Random Number Generator 2986** 2987** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 2988** select random [ROWID | ROWIDs] when inserting new records into a table that 2989** already uses the largest possible [ROWID]. The PRNG is also used for 2990** the built-in random() and randomblob() SQL functions. This interface allows 2991** applications to access the same PRNG for other purposes. 2992** 2993** ^A call to this routine stores N bytes of randomness into buffer P. 2994** ^The P parameter can be a NULL pointer. 2995** 2996** ^If this routine has not been previously called or if the previous 2997** call had N less than one or a NULL pointer for P, then the PRNG is 2998** seeded using randomness obtained from the xRandomness method of 2999** the default [sqlite3_vfs] object. 3000** ^If the previous call to this routine had an N of 1 or more and a 3001** non-NULL P then the pseudo-randomness is generated 3002** internally and without recourse to the [sqlite3_vfs] xRandomness 3003** method. 3004*/ 3005void sqlite3_randomness(int N, void *P); 3006 3007/* 3008** CAPI3REF: Compile-Time Authorization Callbacks 3009** METHOD: sqlite3 3010** KEYWORDS: {authorizer callback} 3011** 3012** ^This routine registers an authorizer callback with a particular 3013** [database connection], supplied in the first argument. 3014** ^The authorizer callback is invoked as SQL statements are being compiled 3015** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 3016** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 3017** and [sqlite3_prepare16_v3()]. ^At various 3018** points during the compilation process, as logic is being created 3019** to perform various actions, the authorizer callback is invoked to 3020** see if those actions are allowed. ^The authorizer callback should 3021** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 3022** specific action but allow the SQL statement to continue to be 3023** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 3024** rejected with an error. ^If the authorizer callback returns 3025** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 3026** then the [sqlite3_prepare_v2()] or equivalent call that triggered 3027** the authorizer will fail with an error message. 3028** 3029** When the callback returns [SQLITE_OK], that means the operation 3030** requested is ok. ^When the callback returns [SQLITE_DENY], the 3031** [sqlite3_prepare_v2()] or equivalent call that triggered the 3032** authorizer will fail with an error message explaining that 3033** access is denied. 3034** 3035** ^The first parameter to the authorizer callback is a copy of the third 3036** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 3037** to the callback is an integer [SQLITE_COPY | action code] that specifies 3038** the particular action to be authorized. ^The third through sixth parameters 3039** to the callback are either NULL pointers or zero-terminated strings 3040** that contain additional details about the action to be authorized. 3041** Applications must always be prepared to encounter a NULL pointer in any 3042** of the third through the sixth parameters of the authorization callback. 3043** 3044** ^If the action code is [SQLITE_READ] 3045** and the callback returns [SQLITE_IGNORE] then the 3046** [prepared statement] statement is constructed to substitute 3047** a NULL value in place of the table column that would have 3048** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 3049** return can be used to deny an untrusted user access to individual 3050** columns of a table. 3051** ^When a table is referenced by a [SELECT] but no column values are 3052** extracted from that table (for example in a query like 3053** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3054** is invoked once for that table with a column name that is an empty string. 3055** ^If the action code is [SQLITE_DELETE] and the callback returns 3056** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3057** [truncate optimization] is disabled and all rows are deleted individually. 3058** 3059** An authorizer is used when [sqlite3_prepare | preparing] 3060** SQL statements from an untrusted source, to ensure that the SQL statements 3061** do not try to access data they are not allowed to see, or that they do not 3062** try to execute malicious statements that damage the database. For 3063** example, an application may allow a user to enter arbitrary 3064** SQL queries for evaluation by a database. But the application does 3065** not want the user to be able to make arbitrary changes to the 3066** database. An authorizer could then be put in place while the 3067** user-entered SQL is being [sqlite3_prepare | prepared] that 3068** disallows everything except [SELECT] statements. 3069** 3070** Applications that need to process SQL from untrusted sources 3071** might also consider lowering resource limits using [sqlite3_limit()] 3072** and limiting database size using the [max_page_count] [PRAGMA] 3073** in addition to using an authorizer. 3074** 3075** ^(Only a single authorizer can be in place on a database connection 3076** at a time. Each call to sqlite3_set_authorizer overrides the 3077** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3078** The authorizer is disabled by default. 3079** 3080** The authorizer callback must not do anything that will modify 3081** the database connection that invoked the authorizer callback. 3082** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3083** database connections for the meaning of "modify" in this paragraph. 3084** 3085** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3086** statement might be re-prepared during [sqlite3_step()] due to a 3087** schema change. Hence, the application should ensure that the 3088** correct authorizer callback remains in place during the [sqlite3_step()]. 3089** 3090** ^Note that the authorizer callback is invoked only during 3091** [sqlite3_prepare()] or its variants. Authorization is not 3092** performed during statement evaluation in [sqlite3_step()], unless 3093** as stated in the previous paragraph, sqlite3_step() invokes 3094** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3095*/ 3096int sqlite3_set_authorizer( 3097 sqlite3*, 3098 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3099 void *pUserData 3100); 3101 3102/* 3103** CAPI3REF: Authorizer Return Codes 3104** 3105** The [sqlite3_set_authorizer | authorizer callback function] must 3106** return either [SQLITE_OK] or one of these two constants in order 3107** to signal SQLite whether or not the action is permitted. See the 3108** [sqlite3_set_authorizer | authorizer documentation] for additional 3109** information. 3110** 3111** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3112** returned from the [sqlite3_vtab_on_conflict()] interface. 3113*/ 3114#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3115#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3116 3117/* 3118** CAPI3REF: Authorizer Action Codes 3119** 3120** The [sqlite3_set_authorizer()] interface registers a callback function 3121** that is invoked to authorize certain SQL statement actions. The 3122** second parameter to the callback is an integer code that specifies 3123** what action is being authorized. These are the integer action codes that 3124** the authorizer callback may be passed. 3125** 3126** These action code values signify what kind of operation is to be 3127** authorized. The 3rd and 4th parameters to the authorization 3128** callback function will be parameters or NULL depending on which of these 3129** codes is used as the second parameter. ^(The 5th parameter to the 3130** authorizer callback is the name of the database ("main", "temp", 3131** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3132** is the name of the inner-most trigger or view that is responsible for 3133** the access attempt or NULL if this access attempt is directly from 3134** top-level SQL code. 3135*/ 3136/******************************************* 3rd ************ 4th ***********/ 3137#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3138#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3139#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3140#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3141#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3142#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3143#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3144#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3145#define SQLITE_DELETE 9 /* Table Name NULL */ 3146#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3147#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3148#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3149#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3150#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3151#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3152#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3153#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3154#define SQLITE_INSERT 18 /* Table Name NULL */ 3155#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3156#define SQLITE_READ 20 /* Table Name Column Name */ 3157#define SQLITE_SELECT 21 /* NULL NULL */ 3158#define SQLITE_TRANSACTION 22 /* Operation NULL */ 3159#define SQLITE_UPDATE 23 /* Table Name Column Name */ 3160#define SQLITE_ATTACH 24 /* Filename NULL */ 3161#define SQLITE_DETACH 25 /* Database Name NULL */ 3162#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3163#define SQLITE_REINDEX 27 /* Index Name NULL */ 3164#define SQLITE_ANALYZE 28 /* Table Name NULL */ 3165#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3166#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3167#define SQLITE_FUNCTION 31 /* NULL Function Name */ 3168#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3169#define SQLITE_COPY 0 /* No longer used */ 3170#define SQLITE_RECURSIVE 33 /* NULL NULL */ 3171 3172/* 3173** CAPI3REF: Tracing And Profiling Functions 3174** METHOD: sqlite3 3175** 3176** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3177** instead of the routines described here. 3178** 3179** These routines register callback functions that can be used for 3180** tracing and profiling the execution of SQL statements. 3181** 3182** ^The callback function registered by sqlite3_trace() is invoked at 3183** various times when an SQL statement is being run by [sqlite3_step()]. 3184** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3185** SQL statement text as the statement first begins executing. 3186** ^(Additional sqlite3_trace() callbacks might occur 3187** as each triggered subprogram is entered. The callbacks for triggers 3188** contain a UTF-8 SQL comment that identifies the trigger.)^ 3189** 3190** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3191** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3192** 3193** ^The callback function registered by sqlite3_profile() is invoked 3194** as each SQL statement finishes. ^The profile callback contains 3195** the original statement text and an estimate of wall-clock time 3196** of how long that statement took to run. ^The profile callback 3197** time is in units of nanoseconds, however the current implementation 3198** is only capable of millisecond resolution so the six least significant 3199** digits in the time are meaningless. Future versions of SQLite 3200** might provide greater resolution on the profiler callback. Invoking 3201** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3202** profile callback. 3203*/ 3204SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3205 void(*xTrace)(void*,const char*), void*); 3206SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3207 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3208 3209/* 3210** CAPI3REF: SQL Trace Event Codes 3211** KEYWORDS: SQLITE_TRACE 3212** 3213** These constants identify classes of events that can be monitored 3214** using the [sqlite3_trace_v2()] tracing logic. The M argument 3215** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3216** the following constants. ^The first argument to the trace callback 3217** is one of the following constants. 3218** 3219** New tracing constants may be added in future releases. 3220** 3221** ^A trace callback has four arguments: xCallback(T,C,P,X). 3222** ^The T argument is one of the integer type codes above. 3223** ^The C argument is a copy of the context pointer passed in as the 3224** fourth argument to [sqlite3_trace_v2()]. 3225** The P and X arguments are pointers whose meanings depend on T. 3226** 3227** <dl> 3228** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3229** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3230** first begins running and possibly at other times during the 3231** execution of the prepared statement, such as at the start of each 3232** trigger subprogram. ^The P argument is a pointer to the 3233** [prepared statement]. ^The X argument is a pointer to a string which 3234** is the unexpanded SQL text of the prepared statement or an SQL comment 3235** that indicates the invocation of a trigger. ^The callback can compute 3236** the same text that would have been returned by the legacy [sqlite3_trace()] 3237** interface by using the X argument when X begins with "--" and invoking 3238** [sqlite3_expanded_sql(P)] otherwise. 3239** 3240** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3241** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3242** information as is provided by the [sqlite3_profile()] callback. 3243** ^The P argument is a pointer to the [prepared statement] and the 3244** X argument points to a 64-bit integer which is the estimated of 3245** the number of nanosecond that the prepared statement took to run. 3246** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3247** 3248** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3249** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3250** statement generates a single row of result. 3251** ^The P argument is a pointer to the [prepared statement] and the 3252** X argument is unused. 3253** 3254** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3255** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3256** connection closes. 3257** ^The P argument is a pointer to the [database connection] object 3258** and the X argument is unused. 3259** </dl> 3260*/ 3261#define SQLITE_TRACE_STMT 0x01 3262#define SQLITE_TRACE_PROFILE 0x02 3263#define SQLITE_TRACE_ROW 0x04 3264#define SQLITE_TRACE_CLOSE 0x08 3265 3266/* 3267** CAPI3REF: SQL Trace Hook 3268** METHOD: sqlite3 3269** 3270** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3271** function X against [database connection] D, using property mask M 3272** and context pointer P. ^If the X callback is 3273** NULL or if the M mask is zero, then tracing is disabled. The 3274** M argument should be the bitwise OR-ed combination of 3275** zero or more [SQLITE_TRACE] constants. 3276** 3277** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 3278** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). 3279** 3280** ^The X callback is invoked whenever any of the events identified by 3281** mask M occur. ^The integer return value from the callback is currently 3282** ignored, though this may change in future releases. Callback 3283** implementations should return zero to ensure future compatibility. 3284** 3285** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3286** ^The T argument is one of the [SQLITE_TRACE] 3287** constants to indicate why the callback was invoked. 3288** ^The C argument is a copy of the context pointer. 3289** The P and X arguments are pointers whose meanings depend on T. 3290** 3291** The sqlite3_trace_v2() interface is intended to replace the legacy 3292** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3293** are deprecated. 3294*/ 3295int sqlite3_trace_v2( 3296 sqlite3*, 3297 unsigned uMask, 3298 int(*xCallback)(unsigned,void*,void*,void*), 3299 void *pCtx 3300); 3301 3302/* 3303** CAPI3REF: Query Progress Callbacks 3304** METHOD: sqlite3 3305** 3306** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3307** function X to be invoked periodically during long running calls to 3308** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 3309** database connection D. An example use for this 3310** interface is to keep a GUI updated during a large query. 3311** 3312** ^The parameter P is passed through as the only parameter to the 3313** callback function X. ^The parameter N is the approximate number of 3314** [virtual machine instructions] that are evaluated between successive 3315** invocations of the callback X. ^If N is less than one then the progress 3316** handler is disabled. 3317** 3318** ^Only a single progress handler may be defined at one time per 3319** [database connection]; setting a new progress handler cancels the 3320** old one. ^Setting parameter X to NULL disables the progress handler. 3321** ^The progress handler is also disabled by setting N to a value less 3322** than 1. 3323** 3324** ^If the progress callback returns non-zero, the operation is 3325** interrupted. This feature can be used to implement a 3326** "Cancel" button on a GUI progress dialog box. 3327** 3328** The progress handler callback must not do anything that will modify 3329** the database connection that invoked the progress handler. 3330** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3331** database connections for the meaning of "modify" in this paragraph. 3332** 3333*/ 3334void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3335 3336/* 3337** CAPI3REF: Opening A New Database Connection 3338** CONSTRUCTOR: sqlite3 3339** 3340** ^These routines open an SQLite database file as specified by the 3341** filename argument. ^The filename argument is interpreted as UTF-8 for 3342** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3343** order for sqlite3_open16(). ^(A [database connection] handle is usually 3344** returned in *ppDb, even if an error occurs. The only exception is that 3345** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3346** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3347** object.)^ ^(If the database is opened (and/or created) successfully, then 3348** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3349** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3350** an English language description of the error following a failure of any 3351** of the sqlite3_open() routines. 3352** 3353** ^The default encoding will be UTF-8 for databases created using 3354** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3355** created using sqlite3_open16() will be UTF-16 in the native byte order. 3356** 3357** Whether or not an error occurs when it is opened, resources 3358** associated with the [database connection] handle should be released by 3359** passing it to [sqlite3_close()] when it is no longer required. 3360** 3361** The sqlite3_open_v2() interface works like sqlite3_open() 3362** except that it accepts two additional parameters for additional control 3363** over the new database connection. ^(The flags parameter to 3364** sqlite3_open_v2() must include, at a minimum, one of the following 3365** three flag combinations:)^ 3366** 3367** <dl> 3368** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3369** <dd>The database is opened in read-only mode. If the database does not 3370** already exist, an error is returned.</dd>)^ 3371** 3372** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3373** <dd>The database is opened for reading and writing if possible, or reading 3374** only if the file is write protected by the operating system. In either 3375** case the database must already exist, otherwise an error is returned.</dd>)^ 3376** 3377** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3378** <dd>The database is opened for reading and writing, and is created if 3379** it does not already exist. This is the behavior that is always used for 3380** sqlite3_open() and sqlite3_open16().</dd>)^ 3381** </dl> 3382** 3383** In addition to the required flags, the following optional flags are 3384** also supported: 3385** 3386** <dl> 3387** ^(<dt>[SQLITE_OPEN_URI]</dt> 3388** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3389** 3390** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3391** <dd>The database will be opened as an in-memory database. The database 3392** is named by the "filename" argument for the purposes of cache-sharing, 3393** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3394** </dd>)^ 3395** 3396** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3397** <dd>The new database connection will use the "multi-thread" 3398** [threading mode].)^ This means that separate threads are allowed 3399** to use SQLite at the same time, as long as each thread is using 3400** a different [database connection]. 3401** 3402** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3403** <dd>The new database connection will use the "serialized" 3404** [threading mode].)^ This means the multiple threads can safely 3405** attempt to use the same database connection at the same time. 3406** (Mutexes will block any actual concurrency, but in this mode 3407** there is no harm in trying.) 3408** 3409** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3410** <dd>The database is opened [shared cache] enabled, overriding 3411** the default shared cache setting provided by 3412** [sqlite3_enable_shared_cache()].)^ 3413** 3414** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3415** <dd>The database is opened [shared cache] disabled, overriding 3416** the default shared cache setting provided by 3417** [sqlite3_enable_shared_cache()].)^ 3418** 3419** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3420** <dd>The database filename is not allowed to be a symbolic link</dd> 3421** 3422** [[OPEN_EXCLUSIVE]] ^(<dt>[SQLITE_OPEN_EXCLUSIVE]</dt> 3423** <dd>This flag causes the open to fail if the database file already 3424** exists. The open will only be success if this flag is used in combination 3425** with the SQLITE_OPEN_CREATE and SQLITE_OPEN_READWRITE flags and if 3426** the file does not previously exist.</dd> 3427** </dl>)^ 3428** 3429** If the 3rd parameter to sqlite3_open_v2() is not one of the 3430** required combinations shown above optionally combined with other 3431** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3432** then the behavior is undefined. 3433** 3434** ^The fourth parameter to sqlite3_open_v2() is the name of the 3435** [sqlite3_vfs] object that defines the operating system interface that 3436** the new database connection should use. ^If the fourth parameter is 3437** a NULL pointer then the default [sqlite3_vfs] object is used. 3438** 3439** ^If the filename is ":memory:", then a private, temporary in-memory database 3440** is created for the connection. ^This in-memory database will vanish when 3441** the database connection is closed. Future versions of SQLite might 3442** make use of additional special filenames that begin with the ":" character. 3443** It is recommended that when a database filename actually does begin with 3444** a ":" character you should prefix the filename with a pathname such as 3445** "./" to avoid ambiguity. 3446** 3447** ^If the filename is an empty string, then a private, temporary 3448** on-disk database will be created. ^This private database will be 3449** automatically deleted as soon as the database connection is closed. 3450** 3451** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3452** 3453** ^If [URI filename] interpretation is enabled, and the filename argument 3454** begins with "file:", then the filename is interpreted as a URI. ^URI 3455** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3456** set in the third argument to sqlite3_open_v2(), or if it has 3457** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3458** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3459** URI filename interpretation is turned off 3460** by default, but future releases of SQLite might enable URI filename 3461** interpretation by default. See "[URI filenames]" for additional 3462** information. 3463** 3464** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3465** authority, then it must be either an empty string or the string 3466** "localhost". ^If the authority is not an empty string or "localhost", an 3467** error is returned to the caller. ^The fragment component of a URI, if 3468** present, is ignored. 3469** 3470** ^SQLite uses the path component of the URI as the name of the disk file 3471** which contains the database. ^If the path begins with a '/' character, 3472** then it is interpreted as an absolute path. ^If the path does not begin 3473** with a '/' (meaning that the authority section is omitted from the URI) 3474** then the path is interpreted as a relative path. 3475** ^(On windows, the first component of an absolute path 3476** is a drive specification (e.g. "C:").)^ 3477** 3478** [[core URI query parameters]] 3479** The query component of a URI may contain parameters that are interpreted 3480** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3481** SQLite and its built-in [VFSes] interpret the 3482** following query parameters: 3483** 3484** <ul> 3485** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3486** a VFS object that provides the operating system interface that should 3487** be used to access the database file on disk. ^If this option is set to 3488** an empty string the default VFS object is used. ^Specifying an unknown 3489** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3490** present, then the VFS specified by the option takes precedence over 3491** the value passed as the fourth parameter to sqlite3_open_v2(). 3492** 3493** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3494** "rwc", or "memory". Attempting to set it to any other value is 3495** an error)^. 3496** ^If "ro" is specified, then the database is opened for read-only 3497** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3498** third argument to sqlite3_open_v2(). ^If the mode option is set to 3499** "rw", then the database is opened for read-write (but not create) 3500** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3501** been set. ^Value "rwc" is equivalent to setting both 3502** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3503** set to "memory" then a pure [in-memory database] that never reads 3504** or writes from disk is used. ^It is an error to specify a value for 3505** the mode parameter that is less restrictive than that specified by 3506** the flags passed in the third parameter to sqlite3_open_v2(). 3507** 3508** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3509** "private". ^Setting it to "shared" is equivalent to setting the 3510** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3511** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3512** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3513** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3514** a URI filename, its value overrides any behavior requested by setting 3515** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3516** 3517** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3518** [powersafe overwrite] property does or does not apply to the 3519** storage media on which the database file resides. 3520** 3521** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3522** which if set disables file locking in rollback journal modes. This 3523** is useful for accessing a database on a filesystem that does not 3524** support locking. Caution: Database corruption might result if two 3525** or more processes write to the same database and any one of those 3526** processes uses nolock=1. 3527** 3528** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3529** parameter that indicates that the database file is stored on 3530** read-only media. ^When immutable is set, SQLite assumes that the 3531** database file cannot be changed, even by a process with higher 3532** privilege, and so the database is opened read-only and all locking 3533** and change detection is disabled. Caution: Setting the immutable 3534** property on a database file that does in fact change can result 3535** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3536** See also: [SQLITE_IOCAP_IMMUTABLE]. 3537** 3538** </ul> 3539** 3540** ^Specifying an unknown parameter in the query component of a URI is not an 3541** error. Future versions of SQLite might understand additional query 3542** parameters. See "[query parameters with special meaning to SQLite]" for 3543** additional information. 3544** 3545** [[URI filename examples]] <h3>URI filename examples</h3> 3546** 3547** <table border="1" align=center cellpadding=5> 3548** <tr><th> URI filenames <th> Results 3549** <tr><td> file:data.db <td> 3550** Open the file "data.db" in the current directory. 3551** <tr><td> file:/home/fred/data.db<br> 3552** file:///home/fred/data.db <br> 3553** file://localhost/home/fred/data.db <br> <td> 3554** Open the database file "/home/fred/data.db". 3555** <tr><td> file://darkstar/home/fred/data.db <td> 3556** An error. "darkstar" is not a recognized authority. 3557** <tr><td style="white-space:nowrap"> 3558** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3559** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3560** C:. Note that the %20 escaping in this example is not strictly 3561** necessary - space characters can be used literally 3562** in URI filenames. 3563** <tr><td> file:data.db?mode=ro&cache=private <td> 3564** Open file "data.db" in the current directory for read-only access. 3565** Regardless of whether or not shared-cache mode is enabled by 3566** default, use a private cache. 3567** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3568** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3569** that uses dot-files in place of posix advisory locking. 3570** <tr><td> file:data.db?mode=readonly <td> 3571** An error. "readonly" is not a valid option for the "mode" parameter. 3572** Use "ro" instead: "file:data.db?mode=ro". 3573** </table> 3574** 3575** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3576** query components of a URI. A hexadecimal escape sequence consists of a 3577** percent sign - "%" - followed by exactly two hexadecimal digits 3578** specifying an octet value. ^Before the path or query components of a 3579** URI filename are interpreted, they are encoded using UTF-8 and all 3580** hexadecimal escape sequences replaced by a single byte containing the 3581** corresponding octet. If this process generates an invalid UTF-8 encoding, 3582** the results are undefined. 3583** 3584** <b>Note to Windows users:</b> The encoding used for the filename argument 3585** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3586** codepage is currently defined. Filenames containing international 3587** characters must be converted to UTF-8 prior to passing them into 3588** sqlite3_open() or sqlite3_open_v2(). 3589** 3590** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3591** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3592** features that require the use of temporary files may fail. 3593** 3594** See also: [sqlite3_temp_directory] 3595*/ 3596int sqlite3_open( 3597 const char *filename, /* Database filename (UTF-8) */ 3598 sqlite3 **ppDb /* OUT: SQLite db handle */ 3599); 3600int sqlite3_open16( 3601 const void *filename, /* Database filename (UTF-16) */ 3602 sqlite3 **ppDb /* OUT: SQLite db handle */ 3603); 3604int sqlite3_open_v2( 3605 const char *filename, /* Database filename (UTF-8) */ 3606 sqlite3 **ppDb, /* OUT: SQLite db handle */ 3607 int flags, /* Flags */ 3608 const char *zVfs /* Name of VFS module to use */ 3609); 3610 3611/* 3612** CAPI3REF: Obtain Values For URI Parameters 3613** 3614** These are utility routines, useful to [VFS|custom VFS implementations], 3615** that check if a database file was a URI that contained a specific query 3616** parameter, and if so obtains the value of that query parameter. 3617** 3618** The first parameter to these interfaces (hereafter referred to 3619** as F) must be one of: 3620** <ul> 3621** <li> A database filename pointer created by the SQLite core and 3622** passed into the xOpen() method of a VFS implemention, or 3623** <li> A filename obtained from [sqlite3_db_filename()], or 3624** <li> A new filename constructed using [sqlite3_create_filename()]. 3625** </ul> 3626** If the F parameter is not one of the above, then the behavior is 3627** undefined and probably undesirable. Older versions of SQLite were 3628** more tolerant of invalid F parameters than newer versions. 3629** 3630** If F is a suitable filename (as described in the previous paragraph) 3631** and if P is the name of the query parameter, then 3632** sqlite3_uri_parameter(F,P) returns the value of the P 3633** parameter if it exists or a NULL pointer if P does not appear as a 3634** query parameter on F. If P is a query parameter of F and it 3635** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3636** a pointer to an empty string. 3637** 3638** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3639** parameter and returns true (1) or false (0) according to the value 3640** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3641** value of query parameter P is one of "yes", "true", or "on" in any 3642** case or if the value begins with a non-zero number. The 3643** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3644** query parameter P is one of "no", "false", or "off" in any case or 3645** if the value begins with a numeric zero. If P is not a query 3646** parameter on F or if the value of P does not match any of the 3647** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3648** 3649** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3650** 64-bit signed integer and returns that integer, or D if P does not 3651** exist. If the value of P is something other than an integer, then 3652** zero is returned. 3653** 3654** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3655** the value) of the N-th query parameter for filename F, or a NULL 3656** pointer if N is less than zero or greater than the number of query 3657** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3658** the name of the first query parameter, 1 for the second parameter, and 3659** so forth. 3660** 3661** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3662** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3663** is not a database file pathname pointer that the SQLite core passed 3664** into the xOpen VFS method, then the behavior of this routine is undefined 3665** and probably undesirable. 3666** 3667** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3668** parameter can also be the name of a rollback journal file or WAL file 3669** in addition to the main database file. Prior to version 3.31.0, these 3670** routines would only work if F was the name of the main database file. 3671** When the F parameter is the name of the rollback journal or WAL file, 3672** it has access to all the same query parameters as were found on the 3673** main database file. 3674** 3675** See the [URI filename] documentation for additional information. 3676*/ 3677const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); 3678int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); 3679sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); 3680const char *sqlite3_uri_key(const char *zFilename, int N); 3681 3682/* 3683** CAPI3REF: Translate filenames 3684** 3685** These routines are available to [VFS|custom VFS implementations] for 3686** translating filenames between the main database file, the journal file, 3687** and the WAL file. 3688** 3689** If F is the name of an sqlite database file, journal file, or WAL file 3690** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3691** returns the name of the corresponding database file. 3692** 3693** If F is the name of an sqlite database file, journal file, or WAL file 3694** passed by the SQLite core into the VFS, or if F is a database filename 3695** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3696** returns the name of the corresponding rollback journal file. 3697** 3698** If F is the name of an sqlite database file, journal file, or WAL file 3699** that was passed by the SQLite core into the VFS, or if F is a database 3700** filename obtained from [sqlite3_db_filename()], then 3701** sqlite3_filename_wal(F) returns the name of the corresponding 3702** WAL file. 3703** 3704** In all of the above, if F is not the name of a database, journal or WAL 3705** filename passed into the VFS from the SQLite core and F is not the 3706** return value from [sqlite3_db_filename()], then the result is 3707** undefined and is likely a memory access violation. 3708*/ 3709const char *sqlite3_filename_database(const char*); 3710const char *sqlite3_filename_journal(const char*); 3711const char *sqlite3_filename_wal(const char*); 3712 3713/* 3714** CAPI3REF: Database File Corresponding To A Journal 3715** 3716** ^If X is the name of a rollback or WAL-mode journal file that is 3717** passed into the xOpen method of [sqlite3_vfs], then 3718** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 3719** object that represents the main database file. 3720** 3721** This routine is intended for use in custom [VFS] implementations 3722** only. It is not a general-purpose interface. 3723** The argument sqlite3_file_object(X) must be a filename pointer that 3724** has been passed into [sqlite3_vfs].xOpen method where the 3725** flags parameter to xOpen contains one of the bits 3726** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 3727** of this routine results in undefined and probably undesirable 3728** behavior. 3729*/ 3730sqlite3_file *sqlite3_database_file_object(const char*); 3731 3732/* 3733** CAPI3REF: Create and Destroy VFS Filenames 3734** 3735** These interfces are provided for use by [VFS shim] implementations and 3736** are not useful outside of that context. 3737** 3738** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 3739** database filename D with corresponding journal file J and WAL file W and 3740** with N URI parameters key/values pairs in the array P. The result from 3741** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 3742** is safe to pass to routines like: 3743** <ul> 3744** <li> [sqlite3_uri_parameter()], 3745** <li> [sqlite3_uri_boolean()], 3746** <li> [sqlite3_uri_int64()], 3747** <li> [sqlite3_uri_key()], 3748** <li> [sqlite3_filename_database()], 3749** <li> [sqlite3_filename_journal()], or 3750** <li> [sqlite3_filename_wal()]. 3751** </ul> 3752** If a memory allocation error occurs, sqlite3_create_filename() might 3753** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 3754** must be released by a corresponding call to sqlite3_free_filename(Y). 3755** 3756** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 3757** of 2*N pointers to strings. Each pair of pointers in this array corresponds 3758** to a key and value for a query parameter. The P parameter may be a NULL 3759** pointer if N is zero. None of the 2*N pointers in the P array may be 3760** NULL pointers and key pointers should not be empty strings. 3761** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 3762** be NULL pointers, though they can be empty strings. 3763** 3764** The sqlite3_free_filename(Y) routine releases a memory allocation 3765** previously obtained from sqlite3_create_filename(). Invoking 3766** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 3767** 3768** If the Y parameter to sqlite3_free_filename(Y) is anything other 3769** than a NULL pointer or a pointer previously acquired from 3770** sqlite3_create_filename(), then bad things such as heap 3771** corruption or segfaults may occur. The value Y should not be 3772** used again after sqlite3_free_filename(Y) has been called. This means 3773** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 3774** then the corresponding [sqlite3_module.xClose() method should also be 3775** invoked prior to calling sqlite3_free_filename(Y). 3776*/ 3777char *sqlite3_create_filename( 3778 const char *zDatabase, 3779 const char *zJournal, 3780 const char *zWal, 3781 int nParam, 3782 const char **azParam 3783); 3784void sqlite3_free_filename(char*); 3785 3786/* 3787** CAPI3REF: Error Codes And Messages 3788** METHOD: sqlite3 3789** 3790** ^If the most recent sqlite3_* API call associated with 3791** [database connection] D failed, then the sqlite3_errcode(D) interface 3792** returns the numeric [result code] or [extended result code] for that 3793** API call. 3794** ^The sqlite3_extended_errcode() 3795** interface is the same except that it always returns the 3796** [extended result code] even when extended result codes are 3797** disabled. 3798** 3799** The values returned by sqlite3_errcode() and/or 3800** sqlite3_extended_errcode() might change with each API call. 3801** Except, there are some interfaces that are guaranteed to never 3802** change the value of the error code. The error-code preserving 3803** interfaces are: 3804** 3805** <ul> 3806** <li> sqlite3_errcode() 3807** <li> sqlite3_extended_errcode() 3808** <li> sqlite3_errmsg() 3809** <li> sqlite3_errmsg16() 3810** </ul> 3811** 3812** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3813** text that describes the error, as either UTF-8 or UTF-16 respectively. 3814** ^(Memory to hold the error message string is managed internally. 3815** The application does not need to worry about freeing the result. 3816** However, the error string might be overwritten or deallocated by 3817** subsequent calls to other SQLite interface functions.)^ 3818** 3819** ^The sqlite3_errstr() interface returns the English-language text 3820** that describes the [result code], as UTF-8. 3821** ^(Memory to hold the error message string is managed internally 3822** and must not be freed by the application)^. 3823** 3824** When the serialized [threading mode] is in use, it might be the 3825** case that a second error occurs on a separate thread in between 3826** the time of the first error and the call to these interfaces. 3827** When that happens, the second error will be reported since these 3828** interfaces always report the most recent result. To avoid 3829** this, each thread can obtain exclusive use of the [database connection] D 3830** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3831** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3832** all calls to the interfaces listed here are completed. 3833** 3834** If an interface fails with SQLITE_MISUSE, that means the interface 3835** was invoked incorrectly by the application. In that case, the 3836** error code and message may or may not be set. 3837*/ 3838int sqlite3_errcode(sqlite3 *db); 3839int sqlite3_extended_errcode(sqlite3 *db); 3840const char *sqlite3_errmsg(sqlite3*); 3841const void *sqlite3_errmsg16(sqlite3*); 3842const char *sqlite3_errstr(int); 3843 3844/* 3845** CAPI3REF: Prepared Statement Object 3846** KEYWORDS: {prepared statement} {prepared statements} 3847** 3848** An instance of this object represents a single SQL statement that 3849** has been compiled into binary form and is ready to be evaluated. 3850** 3851** Think of each SQL statement as a separate computer program. The 3852** original SQL text is source code. A prepared statement object 3853** is the compiled object code. All SQL must be converted into a 3854** prepared statement before it can be run. 3855** 3856** The life-cycle of a prepared statement object usually goes like this: 3857** 3858** <ol> 3859** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3860** <li> Bind values to [parameters] using the sqlite3_bind_*() 3861** interfaces. 3862** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3863** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3864** to step 2. Do this zero or more times. 3865** <li> Destroy the object using [sqlite3_finalize()]. 3866** </ol> 3867*/ 3868typedef struct sqlite3_stmt sqlite3_stmt; 3869 3870/* 3871** CAPI3REF: Run-time Limits 3872** METHOD: sqlite3 3873** 3874** ^(This interface allows the size of various constructs to be limited 3875** on a connection by connection basis. The first parameter is the 3876** [database connection] whose limit is to be set or queried. The 3877** second parameter is one of the [limit categories] that define a 3878** class of constructs to be size limited. The third parameter is the 3879** new limit for that construct.)^ 3880** 3881** ^If the new limit is a negative number, the limit is unchanged. 3882** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3883** [limits | hard upper bound] 3884** set at compile-time by a C preprocessor macro called 3885** [limits | SQLITE_MAX_<i>NAME</i>]. 3886** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3887** ^Attempts to increase a limit above its hard upper bound are 3888** silently truncated to the hard upper bound. 3889** 3890** ^Regardless of whether or not the limit was changed, the 3891** [sqlite3_limit()] interface returns the prior value of the limit. 3892** ^Hence, to find the current value of a limit without changing it, 3893** simply invoke this interface with the third parameter set to -1. 3894** 3895** Run-time limits are intended for use in applications that manage 3896** both their own internal database and also databases that are controlled 3897** by untrusted external sources. An example application might be a 3898** web browser that has its own databases for storing history and 3899** separate databases controlled by JavaScript applications downloaded 3900** off the Internet. The internal databases can be given the 3901** large, default limits. Databases managed by external sources can 3902** be given much smaller limits designed to prevent a denial of service 3903** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3904** interface to further control untrusted SQL. The size of the database 3905** created by an untrusted script can be contained using the 3906** [max_page_count] [PRAGMA]. 3907** 3908** New run-time limit categories may be added in future releases. 3909*/ 3910int sqlite3_limit(sqlite3*, int id, int newVal); 3911 3912/* 3913** CAPI3REF: Run-Time Limit Categories 3914** KEYWORDS: {limit category} {*limit categories} 3915** 3916** These constants define various performance limits 3917** that can be lowered at run-time using [sqlite3_limit()]. 3918** The synopsis of the meanings of the various limits is shown below. 3919** Additional information is available at [limits | Limits in SQLite]. 3920** 3921** <dl> 3922** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3923** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3924** 3925** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3926** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3927** 3928** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3929** <dd>The maximum number of columns in a table definition or in the 3930** result set of a [SELECT] or the maximum number of columns in an index 3931** or in an ORDER BY or GROUP BY clause.</dd>)^ 3932** 3933** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 3934** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 3935** 3936** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 3937** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 3938** 3939** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 3940** <dd>The maximum number of instructions in a virtual machine program 3941** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 3942** the equivalent tries to allocate space for more than this many opcodes 3943** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 3944** 3945** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 3946** <dd>The maximum number of arguments on a function.</dd>)^ 3947** 3948** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 3949** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 3950** 3951** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 3952** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 3953** <dd>The maximum length of the pattern argument to the [LIKE] or 3954** [GLOB] operators.</dd>)^ 3955** 3956** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 3957** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 3958** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 3959** 3960** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 3961** <dd>The maximum depth of recursion for triggers.</dd>)^ 3962** 3963** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 3964** <dd>The maximum number of auxiliary worker threads that a single 3965** [prepared statement] may start.</dd>)^ 3966** </dl> 3967*/ 3968#define SQLITE_LIMIT_LENGTH 0 3969#define SQLITE_LIMIT_SQL_LENGTH 1 3970#define SQLITE_LIMIT_COLUMN 2 3971#define SQLITE_LIMIT_EXPR_DEPTH 3 3972#define SQLITE_LIMIT_COMPOUND_SELECT 4 3973#define SQLITE_LIMIT_VDBE_OP 5 3974#define SQLITE_LIMIT_FUNCTION_ARG 6 3975#define SQLITE_LIMIT_ATTACHED 7 3976#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 3977#define SQLITE_LIMIT_VARIABLE_NUMBER 9 3978#define SQLITE_LIMIT_TRIGGER_DEPTH 10 3979#define SQLITE_LIMIT_WORKER_THREADS 11 3980 3981/* 3982** CAPI3REF: Prepare Flags 3983** 3984** These constants define various flags that can be passed into 3985** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 3986** [sqlite3_prepare16_v3()] interfaces. 3987** 3988** New flags may be added in future releases of SQLite. 3989** 3990** <dl> 3991** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 3992** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 3993** that the prepared statement will be retained for a long time and 3994** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 3995** and [sqlite3_prepare16_v3()] assume that the prepared statement will 3996** be used just once or at most a few times and then destroyed using 3997** [sqlite3_finalize()] relatively soon. The current implementation acts 3998** on this hint by avoiding the use of [lookaside memory] so as not to 3999** deplete the limited store of lookaside memory. Future versions of 4000** SQLite may act on this hint differently. 4001** 4002** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 4003** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 4004** to be required for any prepared statement that wanted to use the 4005** [sqlite3_normalized_sql()] interface. However, the 4006** [sqlite3_normalized_sql()] interface is now available to all 4007** prepared statements, regardless of whether or not they use this 4008** flag. 4009** 4010** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 4011** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 4012** to return an error (error code SQLITE_ERROR) if the statement uses 4013** any virtual tables. 4014** </dl> 4015*/ 4016#define SQLITE_PREPARE_PERSISTENT 0x01 4017#define SQLITE_PREPARE_NORMALIZE 0x02 4018#define SQLITE_PREPARE_NO_VTAB 0x04 4019 4020/* 4021** CAPI3REF: Compiling An SQL Statement 4022** KEYWORDS: {SQL statement compiler} 4023** METHOD: sqlite3 4024** CONSTRUCTOR: sqlite3_stmt 4025** 4026** To execute an SQL statement, it must first be compiled into a byte-code 4027** program using one of these routines. Or, in other words, these routines 4028** are constructors for the [prepared statement] object. 4029** 4030** The preferred routine to use is [sqlite3_prepare_v2()]. The 4031** [sqlite3_prepare()] interface is legacy and should be avoided. 4032** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 4033** for special purposes. 4034** 4035** The use of the UTF-8 interfaces is preferred, as SQLite currently 4036** does all parsing using UTF-8. The UTF-16 interfaces are provided 4037** as a convenience. The UTF-16 interfaces work by converting the 4038** input text into UTF-8, then invoking the corresponding UTF-8 interface. 4039** 4040** The first argument, "db", is a [database connection] obtained from a 4041** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 4042** [sqlite3_open16()]. The database connection must not have been closed. 4043** 4044** The second argument, "zSql", is the statement to be compiled, encoded 4045** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 4046** and sqlite3_prepare_v3() 4047** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 4048** and sqlite3_prepare16_v3() use UTF-16. 4049** 4050** ^If the nByte argument is negative, then zSql is read up to the 4051** first zero terminator. ^If nByte is positive, then it is the 4052** number of bytes read from zSql. ^If nByte is zero, then no prepared 4053** statement is generated. 4054** If the caller knows that the supplied string is nul-terminated, then 4055** there is a small performance advantage to passing an nByte parameter that 4056** is the number of bytes in the input string <i>including</i> 4057** the nul-terminator. 4058** 4059** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4060** past the end of the first SQL statement in zSql. These routines only 4061** compile the first statement in zSql, so *pzTail is left pointing to 4062** what remains uncompiled. 4063** 4064** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4065** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4066** to NULL. ^If the input text contains no SQL (if the input is an empty 4067** string or a comment) then *ppStmt is set to NULL. 4068** The calling procedure is responsible for deleting the compiled 4069** SQL statement using [sqlite3_finalize()] after it has finished with it. 4070** ppStmt may not be NULL. 4071** 4072** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4073** otherwise an [error code] is returned. 4074** 4075** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4076** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4077** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4078** are retained for backwards compatibility, but their use is discouraged. 4079** ^In the "vX" interfaces, the prepared statement 4080** that is returned (the [sqlite3_stmt] object) contains a copy of the 4081** original SQL text. This causes the [sqlite3_step()] interface to 4082** behave differently in three ways: 4083** 4084** <ol> 4085** <li> 4086** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4087** always used to do, [sqlite3_step()] will automatically recompile the SQL 4088** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4089** retries will occur before sqlite3_step() gives up and returns an error. 4090** </li> 4091** 4092** <li> 4093** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4094** [error codes] or [extended error codes]. ^The legacy behavior was that 4095** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4096** and the application would have to make a second call to [sqlite3_reset()] 4097** in order to find the underlying cause of the problem. With the "v2" prepare 4098** interfaces, the underlying reason for the error is returned immediately. 4099** </li> 4100** 4101** <li> 4102** ^If the specific value bound to a [parameter | host parameter] in the 4103** WHERE clause might influence the choice of query plan for a statement, 4104** then the statement will be automatically recompiled, as if there had been 4105** a schema change, on the first [sqlite3_step()] call following any change 4106** to the [sqlite3_bind_text | bindings] of that [parameter]. 4107** ^The specific value of a WHERE-clause [parameter] might influence the 4108** choice of query plan if the parameter is the left-hand side of a [LIKE] 4109** or [GLOB] operator or if the parameter is compared to an indexed column 4110** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4111** </li> 4112** </ol> 4113** 4114** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4115** the extra prepFlags parameter, which is a bit array consisting of zero or 4116** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4117** sqlite3_prepare_v2() interface works exactly the same as 4118** sqlite3_prepare_v3() with a zero prepFlags parameter. 4119*/ 4120int sqlite3_prepare( 4121 sqlite3 *db, /* Database handle */ 4122 const char *zSql, /* SQL statement, UTF-8 encoded */ 4123 int nByte, /* Maximum length of zSql in bytes. */ 4124 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4125 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4126); 4127int sqlite3_prepare_v2( 4128 sqlite3 *db, /* Database handle */ 4129 const char *zSql, /* SQL statement, UTF-8 encoded */ 4130 int nByte, /* Maximum length of zSql in bytes. */ 4131 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4132 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4133); 4134int sqlite3_prepare_v3( 4135 sqlite3 *db, /* Database handle */ 4136 const char *zSql, /* SQL statement, UTF-8 encoded */ 4137 int nByte, /* Maximum length of zSql in bytes. */ 4138 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4139 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4140 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4141); 4142int sqlite3_prepare16( 4143 sqlite3 *db, /* Database handle */ 4144 const void *zSql, /* SQL statement, UTF-16 encoded */ 4145 int nByte, /* Maximum length of zSql in bytes. */ 4146 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4147 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4148); 4149int sqlite3_prepare16_v2( 4150 sqlite3 *db, /* Database handle */ 4151 const void *zSql, /* SQL statement, UTF-16 encoded */ 4152 int nByte, /* Maximum length of zSql in bytes. */ 4153 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4154 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4155); 4156int sqlite3_prepare16_v3( 4157 sqlite3 *db, /* Database handle */ 4158 const void *zSql, /* SQL statement, UTF-16 encoded */ 4159 int nByte, /* Maximum length of zSql in bytes. */ 4160 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4161 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4162 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4163); 4164 4165/* 4166** CAPI3REF: Retrieving Statement SQL 4167** METHOD: sqlite3_stmt 4168** 4169** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4170** SQL text used to create [prepared statement] P if P was 4171** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4172** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4173** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4174** string containing the SQL text of prepared statement P with 4175** [bound parameters] expanded. 4176** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4177** string containing the normalized SQL text of prepared statement P. The 4178** semantics used to normalize a SQL statement are unspecified and subject 4179** to change. At a minimum, literal values will be replaced with suitable 4180** placeholders. 4181** 4182** ^(For example, if a prepared statement is created using the SQL 4183** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4184** and parameter :xyz is unbound, then sqlite3_sql() will return 4185** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4186** will return "SELECT 2345,NULL".)^ 4187** 4188** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4189** is available to hold the result, or if the result would exceed the 4190** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4191** 4192** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4193** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4194** option causes sqlite3_expanded_sql() to always return NULL. 4195** 4196** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4197** are managed by SQLite and are automatically freed when the prepared 4198** statement is finalized. 4199** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4200** is obtained from [sqlite3_malloc()] and must be freed by the application 4201** by passing it to [sqlite3_free()]. 4202** 4203** ^The sqlite3_normalized_sql() interface is only available if 4204** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. 4205*/ 4206const char *sqlite3_sql(sqlite3_stmt *pStmt); 4207char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4208#ifdef SQLITE_ENABLE_NORMALIZE 4209const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4210#endif 4211 4212/* 4213** CAPI3REF: Determine If An SQL Statement Writes The Database 4214** METHOD: sqlite3_stmt 4215** 4216** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4217** and only if the [prepared statement] X makes no direct changes to 4218** the content of the database file. 4219** 4220** Note that [application-defined SQL functions] or 4221** [virtual tables] might change the database indirectly as a side effect. 4222** ^(For example, if an application defines a function "eval()" that 4223** calls [sqlite3_exec()], then the following SQL statement would 4224** change the database file through side-effects: 4225** 4226** <blockquote><pre> 4227** SELECT eval('DELETE FROM t1') FROM t2; 4228** </pre></blockquote> 4229** 4230** But because the [SELECT] statement does not change the database file 4231** directly, sqlite3_stmt_readonly() would still return true.)^ 4232** 4233** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4234** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4235** since the statements themselves do not actually modify the database but 4236** rather they control the timing of when other statements modify the 4237** database. ^The [ATTACH] and [DETACH] statements also cause 4238** sqlite3_stmt_readonly() to return true since, while those statements 4239** change the configuration of a database connection, they do not make 4240** changes to the content of the database files on disk. 4241** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4242** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4243** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4244** sqlite3_stmt_readonly() returns false for those commands. 4245** 4246** ^This routine returns false if there is any possibility that the 4247** statement might change the database file. ^A false return does 4248** not guarantee that the statement will change the database file. 4249** ^For example, an UPDATE statement might have a WHERE clause that 4250** makes it a no-op, but the sqlite3_stmt_readonly() result would still 4251** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a 4252** read-only no-op if the table already exists, but 4253** sqlite3_stmt_readonly() still returns false for such a statement. 4254*/ 4255int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4256 4257/* 4258** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4259** METHOD: sqlite3_stmt 4260** 4261** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4262** prepared statement S is an EXPLAIN statement, or 2 if the 4263** statement S is an EXPLAIN QUERY PLAN. 4264** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4265** an ordinary statement or a NULL pointer. 4266*/ 4267int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4268 4269/* 4270** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4271** METHOD: sqlite3_stmt 4272** 4273** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4274** [prepared statement] S has been stepped at least once using 4275** [sqlite3_step(S)] but has neither run to completion (returned 4276** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4277** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4278** interface returns false if S is a NULL pointer. If S is not a 4279** NULL pointer and is not a pointer to a valid [prepared statement] 4280** object, then the behavior is undefined and probably undesirable. 4281** 4282** This interface can be used in combination [sqlite3_next_stmt()] 4283** to locate all prepared statements associated with a database 4284** connection that are in need of being reset. This can be used, 4285** for example, in diagnostic routines to search for prepared 4286** statements that are holding a transaction open. 4287*/ 4288int sqlite3_stmt_busy(sqlite3_stmt*); 4289 4290/* 4291** CAPI3REF: Dynamically Typed Value Object 4292** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4293** 4294** SQLite uses the sqlite3_value object to represent all values 4295** that can be stored in a database table. SQLite uses dynamic typing 4296** for the values it stores. ^Values stored in sqlite3_value objects 4297** can be integers, floating point values, strings, BLOBs, or NULL. 4298** 4299** An sqlite3_value object may be either "protected" or "unprotected". 4300** Some interfaces require a protected sqlite3_value. Other interfaces 4301** will accept either a protected or an unprotected sqlite3_value. 4302** Every interface that accepts sqlite3_value arguments specifies 4303** whether or not it requires a protected sqlite3_value. The 4304** [sqlite3_value_dup()] interface can be used to construct a new 4305** protected sqlite3_value from an unprotected sqlite3_value. 4306** 4307** The terms "protected" and "unprotected" refer to whether or not 4308** a mutex is held. An internal mutex is held for a protected 4309** sqlite3_value object but no mutex is held for an unprotected 4310** sqlite3_value object. If SQLite is compiled to be single-threaded 4311** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4312** or if SQLite is run in one of reduced mutex modes 4313** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4314** then there is no distinction between protected and unprotected 4315** sqlite3_value objects and they can be used interchangeably. However, 4316** for maximum code portability it is recommended that applications 4317** still make the distinction between protected and unprotected 4318** sqlite3_value objects even when not strictly required. 4319** 4320** ^The sqlite3_value objects that are passed as parameters into the 4321** implementation of [application-defined SQL functions] are protected. 4322** ^The sqlite3_value object returned by 4323** [sqlite3_column_value()] is unprotected. 4324** Unprotected sqlite3_value objects may only be used as arguments 4325** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4326** [sqlite3_value_dup()]. 4327** The [sqlite3_value_blob | sqlite3_value_type()] family of 4328** interfaces require protected sqlite3_value objects. 4329*/ 4330typedef struct sqlite3_value sqlite3_value; 4331 4332/* 4333** CAPI3REF: SQL Function Context Object 4334** 4335** The context in which an SQL function executes is stored in an 4336** sqlite3_context object. ^A pointer to an sqlite3_context object 4337** is always first parameter to [application-defined SQL functions]. 4338** The application-defined SQL function implementation will pass this 4339** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4340** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4341** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4342** and/or [sqlite3_set_auxdata()]. 4343*/ 4344typedef struct sqlite3_context sqlite3_context; 4345 4346/* 4347** CAPI3REF: Binding Values To Prepared Statements 4348** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4349** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4350** METHOD: sqlite3_stmt 4351** 4352** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4353** literals may be replaced by a [parameter] that matches one of following 4354** templates: 4355** 4356** <ul> 4357** <li> ? 4358** <li> ?NNN 4359** <li> :VVV 4360** <li> @VVV 4361** <li> $VVV 4362** </ul> 4363** 4364** In the templates above, NNN represents an integer literal, 4365** and VVV represents an alphanumeric identifier.)^ ^The values of these 4366** parameters (also called "host parameter names" or "SQL parameters") 4367** can be set using the sqlite3_bind_*() routines defined here. 4368** 4369** ^The first argument to the sqlite3_bind_*() routines is always 4370** a pointer to the [sqlite3_stmt] object returned from 4371** [sqlite3_prepare_v2()] or its variants. 4372** 4373** ^The second argument is the index of the SQL parameter to be set. 4374** ^The leftmost SQL parameter has an index of 1. ^When the same named 4375** SQL parameter is used more than once, second and subsequent 4376** occurrences have the same index as the first occurrence. 4377** ^The index for named parameters can be looked up using the 4378** [sqlite3_bind_parameter_index()] API if desired. ^The index 4379** for "?NNN" parameters is the value of NNN. 4380** ^The NNN value must be between 1 and the [sqlite3_limit()] 4381** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4382** 4383** ^The third argument is the value to bind to the parameter. 4384** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4385** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4386** is ignored and the end result is the same as sqlite3_bind_null(). 4387** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4388** it should be a pointer to well-formed UTF8 text. 4389** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4390** it should be a pointer to well-formed UTF16 text. 4391** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4392** it should be a pointer to a well-formed unicode string that is 4393** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 4394** otherwise. 4395** 4396** [[byte-order determination rules]] ^The byte-order of 4397** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4398** found in first character, which is removed, or in the absence of a BOM 4399** the byte order is the native byte order of the host 4400** machine for sqlite3_bind_text16() or the byte order specified in 4401** the 6th parameter for sqlite3_bind_text64().)^ 4402** ^If UTF16 input text contains invalid unicode 4403** characters, then SQLite might change those invalid characters 4404** into the unicode replacement character: U+FFFD. 4405** 4406** ^(In those routines that have a fourth argument, its value is the 4407** number of bytes in the parameter. To be clear: the value is the 4408** number of <u>bytes</u> in the value, not the number of characters.)^ 4409** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4410** is negative, then the length of the string is 4411** the number of bytes up to the first zero terminator. 4412** If the fourth parameter to sqlite3_bind_blob() is negative, then 4413** the behavior is undefined. 4414** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4415** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4416** that parameter must be the byte offset 4417** where the NUL terminator would occur assuming the string were NUL 4418** terminated. If any NUL characters occurs at byte offsets less than 4419** the value of the fourth parameter then the resulting string value will 4420** contain embedded NULs. The result of expressions involving strings 4421** with embedded NULs is undefined. 4422** 4423** ^The fifth argument to the BLOB and string binding interfaces controls 4424** or indicates the lifetime of the object referenced by the third parameter. 4425** These three options exist: 4426** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished 4427** with it may be passed. ^It is called to dispose of the BLOB or string even 4428** if the call to the bind API fails, except the destructor is not called if 4429** the third parameter is a NULL pointer or the fourth parameter is negative. 4430** ^ (2) The special constant, [SQLITE_STATIC], may be passsed to indicate that 4431** the application remains responsible for disposing of the object. ^In this 4432** case, the object and the provided pointer to it must remain valid until 4433** either the prepared statement is finalized or the same SQL parameter is 4434** bound to something else, whichever occurs sooner. 4435** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the 4436** object is to be copied prior to the return from sqlite3_bind_*(). ^The 4437** object and pointer to it must remain valid until then. ^SQLite will then 4438** manage the lifetime of its private copy. 4439** 4440** ^The sixth argument to sqlite3_bind_text64() must be one of 4441** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4442** to specify the encoding of the text in the third parameter. If 4443** the sixth argument to sqlite3_bind_text64() is not one of the 4444** allowed values shown above, or if the text encoding is different 4445** from the encoding specified by the sixth parameter, then the behavior 4446** is undefined. 4447** 4448** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4449** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4450** (just an integer to hold its size) while it is being processed. 4451** Zeroblobs are intended to serve as placeholders for BLOBs whose 4452** content is later written using 4453** [sqlite3_blob_open | incremental BLOB I/O] routines. 4454** ^A negative value for the zeroblob results in a zero-length BLOB. 4455** 4456** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4457** [prepared statement] S to have an SQL value of NULL, but to also be 4458** associated with the pointer P of type T. ^D is either a NULL pointer or 4459** a pointer to a destructor function for P. ^SQLite will invoke the 4460** destructor D with a single argument of P when it is finished using 4461** P. The T parameter should be a static string, preferably a string 4462** literal. The sqlite3_bind_pointer() routine is part of the 4463** [pointer passing interface] added for SQLite 3.20.0. 4464** 4465** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4466** for the [prepared statement] or with a prepared statement for which 4467** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4468** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4469** routine is passed a [prepared statement] that has been finalized, the 4470** result is undefined and probably harmful. 4471** 4472** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4473** ^Unbound parameters are interpreted as NULL. 4474** 4475** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4476** [error code] if anything goes wrong. 4477** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4478** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4479** [SQLITE_MAX_LENGTH]. 4480** ^[SQLITE_RANGE] is returned if the parameter 4481** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4482** 4483** See also: [sqlite3_bind_parameter_count()], 4484** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4485*/ 4486int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4487int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4488 void(*)(void*)); 4489int sqlite3_bind_double(sqlite3_stmt*, int, double); 4490int sqlite3_bind_int(sqlite3_stmt*, int, int); 4491int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4492int sqlite3_bind_null(sqlite3_stmt*, int); 4493int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4494int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4495int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4496 void(*)(void*), unsigned char encoding); 4497int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4498int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4499int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4500int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4501 4502/* 4503** CAPI3REF: Number Of SQL Parameters 4504** METHOD: sqlite3_stmt 4505** 4506** ^This routine can be used to find the number of [SQL parameters] 4507** in a [prepared statement]. SQL parameters are tokens of the 4508** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4509** placeholders for values that are [sqlite3_bind_blob | bound] 4510** to the parameters at a later time. 4511** 4512** ^(This routine actually returns the index of the largest (rightmost) 4513** parameter. For all forms except ?NNN, this will correspond to the 4514** number of unique parameters. If parameters of the ?NNN form are used, 4515** there may be gaps in the list.)^ 4516** 4517** See also: [sqlite3_bind_blob|sqlite3_bind()], 4518** [sqlite3_bind_parameter_name()], and 4519** [sqlite3_bind_parameter_index()]. 4520*/ 4521int sqlite3_bind_parameter_count(sqlite3_stmt*); 4522 4523/* 4524** CAPI3REF: Name Of A Host Parameter 4525** METHOD: sqlite3_stmt 4526** 4527** ^The sqlite3_bind_parameter_name(P,N) interface returns 4528** the name of the N-th [SQL parameter] in the [prepared statement] P. 4529** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4530** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4531** respectively. 4532** In other words, the initial ":" or "$" or "@" or "?" 4533** is included as part of the name.)^ 4534** ^Parameters of the form "?" without a following integer have no name 4535** and are referred to as "nameless" or "anonymous parameters". 4536** 4537** ^The first host parameter has an index of 1, not 0. 4538** 4539** ^If the value N is out of range or if the N-th parameter is 4540** nameless, then NULL is returned. ^The returned string is 4541** always in UTF-8 encoding even if the named parameter was 4542** originally specified as UTF-16 in [sqlite3_prepare16()], 4543** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4544** 4545** See also: [sqlite3_bind_blob|sqlite3_bind()], 4546** [sqlite3_bind_parameter_count()], and 4547** [sqlite3_bind_parameter_index()]. 4548*/ 4549const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4550 4551/* 4552** CAPI3REF: Index Of A Parameter With A Given Name 4553** METHOD: sqlite3_stmt 4554** 4555** ^Return the index of an SQL parameter given its name. ^The 4556** index value returned is suitable for use as the second 4557** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4558** is returned if no matching parameter is found. ^The parameter 4559** name must be given in UTF-8 even if the original statement 4560** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4561** [sqlite3_prepare16_v3()]. 4562** 4563** See also: [sqlite3_bind_blob|sqlite3_bind()], 4564** [sqlite3_bind_parameter_count()], and 4565** [sqlite3_bind_parameter_name()]. 4566*/ 4567int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4568 4569/* 4570** CAPI3REF: Reset All Bindings On A Prepared Statement 4571** METHOD: sqlite3_stmt 4572** 4573** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4574** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4575** ^Use this routine to reset all host parameters to NULL. 4576*/ 4577int sqlite3_clear_bindings(sqlite3_stmt*); 4578 4579/* 4580** CAPI3REF: Number Of Columns In A Result Set 4581** METHOD: sqlite3_stmt 4582** 4583** ^Return the number of columns in the result set returned by the 4584** [prepared statement]. ^If this routine returns 0, that means the 4585** [prepared statement] returns no data (for example an [UPDATE]). 4586** ^However, just because this routine returns a positive number does not 4587** mean that one or more rows of data will be returned. ^A SELECT statement 4588** will always have a positive sqlite3_column_count() but depending on the 4589** WHERE clause constraints and the table content, it might return no rows. 4590** 4591** See also: [sqlite3_data_count()] 4592*/ 4593int sqlite3_column_count(sqlite3_stmt *pStmt); 4594 4595/* 4596** CAPI3REF: Column Names In A Result Set 4597** METHOD: sqlite3_stmt 4598** 4599** ^These routines return the name assigned to a particular column 4600** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4601** interface returns a pointer to a zero-terminated UTF-8 string 4602** and sqlite3_column_name16() returns a pointer to a zero-terminated 4603** UTF-16 string. ^The first parameter is the [prepared statement] 4604** that implements the [SELECT] statement. ^The second parameter is the 4605** column number. ^The leftmost column is number 0. 4606** 4607** ^The returned string pointer is valid until either the [prepared statement] 4608** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4609** reprepared by the first call to [sqlite3_step()] for a particular run 4610** or until the next call to 4611** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4612** 4613** ^If sqlite3_malloc() fails during the processing of either routine 4614** (for example during a conversion from UTF-8 to UTF-16) then a 4615** NULL pointer is returned. 4616** 4617** ^The name of a result column is the value of the "AS" clause for 4618** that column, if there is an AS clause. If there is no AS clause 4619** then the name of the column is unspecified and may change from 4620** one release of SQLite to the next. 4621*/ 4622const char *sqlite3_column_name(sqlite3_stmt*, int N); 4623const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4624 4625/* 4626** CAPI3REF: Source Of Data In A Query Result 4627** METHOD: sqlite3_stmt 4628** 4629** ^These routines provide a means to determine the database, table, and 4630** table column that is the origin of a particular result column in 4631** [SELECT] statement. 4632** ^The name of the database or table or column can be returned as 4633** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4634** the database name, the _table_ routines return the table name, and 4635** the origin_ routines return the column name. 4636** ^The returned string is valid until the [prepared statement] is destroyed 4637** using [sqlite3_finalize()] or until the statement is automatically 4638** reprepared by the first call to [sqlite3_step()] for a particular run 4639** or until the same information is requested 4640** again in a different encoding. 4641** 4642** ^The names returned are the original un-aliased names of the 4643** database, table, and column. 4644** 4645** ^The first argument to these interfaces is a [prepared statement]. 4646** ^These functions return information about the Nth result column returned by 4647** the statement, where N is the second function argument. 4648** ^The left-most column is column 0 for these routines. 4649** 4650** ^If the Nth column returned by the statement is an expression or 4651** subquery and is not a column value, then all of these functions return 4652** NULL. ^These routines might also return NULL if a memory allocation error 4653** occurs. ^Otherwise, they return the name of the attached database, table, 4654** or column that query result column was extracted from. 4655** 4656** ^As with all other SQLite APIs, those whose names end with "16" return 4657** UTF-16 encoded strings and the other functions return UTF-8. 4658** 4659** ^These APIs are only available if the library was compiled with the 4660** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4661** 4662** If two or more threads call one or more 4663** [sqlite3_column_database_name | column metadata interfaces] 4664** for the same [prepared statement] and result column 4665** at the same time then the results are undefined. 4666*/ 4667const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4668const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4669const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4670const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4671const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4672const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4673 4674/* 4675** CAPI3REF: Declared Datatype Of A Query Result 4676** METHOD: sqlite3_stmt 4677** 4678** ^(The first parameter is a [prepared statement]. 4679** If this statement is a [SELECT] statement and the Nth column of the 4680** returned result set of that [SELECT] is a table column (not an 4681** expression or subquery) then the declared type of the table 4682** column is returned.)^ ^If the Nth column of the result set is an 4683** expression or subquery, then a NULL pointer is returned. 4684** ^The returned string is always UTF-8 encoded. 4685** 4686** ^(For example, given the database schema: 4687** 4688** CREATE TABLE t1(c1 VARIANT); 4689** 4690** and the following statement to be compiled: 4691** 4692** SELECT c1 + 1, c1 FROM t1; 4693** 4694** this routine would return the string "VARIANT" for the second result 4695** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4696** 4697** ^SQLite uses dynamic run-time typing. ^So just because a column 4698** is declared to contain a particular type does not mean that the 4699** data stored in that column is of the declared type. SQLite is 4700** strongly typed, but the typing is dynamic not static. ^Type 4701** is associated with individual values, not with the containers 4702** used to hold those values. 4703*/ 4704const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4705const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4706 4707/* 4708** CAPI3REF: Evaluate An SQL Statement 4709** METHOD: sqlite3_stmt 4710** 4711** After a [prepared statement] has been prepared using any of 4712** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4713** or [sqlite3_prepare16_v3()] or one of the legacy 4714** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4715** must be called one or more times to evaluate the statement. 4716** 4717** The details of the behavior of the sqlite3_step() interface depend 4718** on whether the statement was prepared using the newer "vX" interfaces 4719** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4720** [sqlite3_prepare16_v2()] or the older legacy 4721** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4722** new "vX" interface is recommended for new applications but the legacy 4723** interface will continue to be supported. 4724** 4725** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4726** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4727** ^With the "v2" interface, any of the other [result codes] or 4728** [extended result codes] might be returned as well. 4729** 4730** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4731** database locks it needs to do its job. ^If the statement is a [COMMIT] 4732** or occurs outside of an explicit transaction, then you can retry the 4733** statement. If the statement is not a [COMMIT] and occurs within an 4734** explicit transaction then you should rollback the transaction before 4735** continuing. 4736** 4737** ^[SQLITE_DONE] means that the statement has finished executing 4738** successfully. sqlite3_step() should not be called again on this virtual 4739** machine without first calling [sqlite3_reset()] to reset the virtual 4740** machine back to its initial state. 4741** 4742** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4743** is returned each time a new row of data is ready for processing by the 4744** caller. The values may be accessed using the [column access functions]. 4745** sqlite3_step() is called again to retrieve the next row of data. 4746** 4747** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4748** violation) has occurred. sqlite3_step() should not be called again on 4749** the VM. More information may be found by calling [sqlite3_errmsg()]. 4750** ^With the legacy interface, a more specific error code (for example, 4751** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4752** can be obtained by calling [sqlite3_reset()] on the 4753** [prepared statement]. ^In the "v2" interface, 4754** the more specific error code is returned directly by sqlite3_step(). 4755** 4756** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4757** Perhaps it was called on a [prepared statement] that has 4758** already been [sqlite3_finalize | finalized] or on one that had 4759** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4760** be the case that the same database connection is being used by two or 4761** more threads at the same moment in time. 4762** 4763** For all versions of SQLite up to and including 3.6.23.1, a call to 4764** [sqlite3_reset()] was required after sqlite3_step() returned anything 4765** other than [SQLITE_ROW] before any subsequent invocation of 4766** sqlite3_step(). Failure to reset the prepared statement using 4767** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4768** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4769** sqlite3_step() began 4770** calling [sqlite3_reset()] automatically in this circumstance rather 4771** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4772** break because any application that ever receives an SQLITE_MISUSE error 4773** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4774** can be used to restore the legacy behavior. 4775** 4776** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4777** API always returns a generic error code, [SQLITE_ERROR], following any 4778** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4779** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4780** specific [error codes] that better describes the error. 4781** We admit that this is a goofy design. The problem has been fixed 4782** with the "v2" interface. If you prepare all of your SQL statements 4783** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4784** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 4785** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 4786** then the more specific [error codes] are returned directly 4787** by sqlite3_step(). The use of the "vX" interfaces is recommended. 4788*/ 4789int sqlite3_step(sqlite3_stmt*); 4790 4791/* 4792** CAPI3REF: Number of columns in a result set 4793** METHOD: sqlite3_stmt 4794** 4795** ^The sqlite3_data_count(P) interface returns the number of columns in the 4796** current row of the result set of [prepared statement] P. 4797** ^If prepared statement P does not have results ready to return 4798** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 4799** interfaces) then sqlite3_data_count(P) returns 0. 4800** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 4801** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 4802** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 4803** will return non-zero if previous call to [sqlite3_step](P) returned 4804** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 4805** where it always returns zero since each step of that multi-step 4806** pragma returns 0 columns of data. 4807** 4808** See also: [sqlite3_column_count()] 4809*/ 4810int sqlite3_data_count(sqlite3_stmt *pStmt); 4811 4812/* 4813** CAPI3REF: Fundamental Datatypes 4814** KEYWORDS: SQLITE_TEXT 4815** 4816** ^(Every value in SQLite has one of five fundamental datatypes: 4817** 4818** <ul> 4819** <li> 64-bit signed integer 4820** <li> 64-bit IEEE floating point number 4821** <li> string 4822** <li> BLOB 4823** <li> NULL 4824** </ul>)^ 4825** 4826** These constants are codes for each of those types. 4827** 4828** Note that the SQLITE_TEXT constant was also used in SQLite version 2 4829** for a completely different meaning. Software that links against both 4830** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 4831** SQLITE_TEXT. 4832*/ 4833#define SQLITE_INTEGER 1 4834#define SQLITE_FLOAT 2 4835#define SQLITE_BLOB 4 4836#define SQLITE_NULL 5 4837#ifdef SQLITE_TEXT 4838# undef SQLITE_TEXT 4839#else 4840# define SQLITE_TEXT 3 4841#endif 4842#define SQLITE3_TEXT 3 4843 4844/* 4845** CAPI3REF: Result Values From A Query 4846** KEYWORDS: {column access functions} 4847** METHOD: sqlite3_stmt 4848** 4849** <b>Summary:</b> 4850** <blockquote><table border=0 cellpadding=0 cellspacing=0> 4851** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 4852** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 4853** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 4854** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 4855** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 4856** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 4857** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 4858** [sqlite3_value|unprotected sqlite3_value] object. 4859** <tr><td> <td> <td> 4860** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 4861** or a UTF-8 TEXT result in bytes 4862** <tr><td><b>sqlite3_column_bytes16 </b> 4863** <td>→ <td>Size of UTF-16 4864** TEXT in bytes 4865** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 4866** datatype of the result 4867** </table></blockquote> 4868** 4869** <b>Details:</b> 4870** 4871** ^These routines return information about a single column of the current 4872** result row of a query. ^In every case the first argument is a pointer 4873** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 4874** that was returned from [sqlite3_prepare_v2()] or one of its variants) 4875** and the second argument is the index of the column for which information 4876** should be returned. ^The leftmost column of the result set has the index 0. 4877** ^The number of columns in the result can be determined using 4878** [sqlite3_column_count()]. 4879** 4880** If the SQL statement does not currently point to a valid row, or if the 4881** column index is out of range, the result is undefined. 4882** These routines may only be called when the most recent call to 4883** [sqlite3_step()] has returned [SQLITE_ROW] and neither 4884** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 4885** If any of these routines are called after [sqlite3_reset()] or 4886** [sqlite3_finalize()] or after [sqlite3_step()] has returned 4887** something other than [SQLITE_ROW], the results are undefined. 4888** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 4889** are called from a different thread while any of these routines 4890** are pending, then the results are undefined. 4891** 4892** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 4893** each return the value of a result column in a specific data format. If 4894** the result column is not initially in the requested format (for example, 4895** if the query returns an integer but the sqlite3_column_text() interface 4896** is used to extract the value) then an automatic type conversion is performed. 4897** 4898** ^The sqlite3_column_type() routine returns the 4899** [SQLITE_INTEGER | datatype code] for the initial data type 4900** of the result column. ^The returned value is one of [SQLITE_INTEGER], 4901** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 4902** The return value of sqlite3_column_type() can be used to decide which 4903** of the first six interface should be used to extract the column value. 4904** The value returned by sqlite3_column_type() is only meaningful if no 4905** automatic type conversions have occurred for the value in question. 4906** After a type conversion, the result of calling sqlite3_column_type() 4907** is undefined, though harmless. Future 4908** versions of SQLite may change the behavior of sqlite3_column_type() 4909** following a type conversion. 4910** 4911** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 4912** or sqlite3_column_bytes16() interfaces can be used to determine the size 4913** of that BLOB or string. 4914** 4915** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 4916** routine returns the number of bytes in that BLOB or string. 4917** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 4918** the string to UTF-8 and then returns the number of bytes. 4919** ^If the result is a numeric value then sqlite3_column_bytes() uses 4920** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 4921** the number of bytes in that string. 4922** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 4923** 4924** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 4925** routine returns the number of bytes in that BLOB or string. 4926** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 4927** the string to UTF-16 and then returns the number of bytes. 4928** ^If the result is a numeric value then sqlite3_column_bytes16() uses 4929** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 4930** the number of bytes in that string. 4931** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 4932** 4933** ^The values returned by [sqlite3_column_bytes()] and 4934** [sqlite3_column_bytes16()] do not include the zero terminators at the end 4935** of the string. ^For clarity: the values returned by 4936** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 4937** bytes in the string, not the number of characters. 4938** 4939** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 4940** even empty strings, are always zero-terminated. ^The return 4941** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 4942** 4943** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 4944** [unprotected sqlite3_value] object. In a multithreaded environment, 4945** an unprotected sqlite3_value object may only be used safely with 4946** [sqlite3_bind_value()] and [sqlite3_result_value()]. 4947** If the [unprotected sqlite3_value] object returned by 4948** [sqlite3_column_value()] is used in any other way, including calls 4949** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 4950** or [sqlite3_value_bytes()], the behavior is not threadsafe. 4951** Hence, the sqlite3_column_value() interface 4952** is normally only useful within the implementation of 4953** [application-defined SQL functions] or [virtual tables], not within 4954** top-level application code. 4955** 4956** The these routines may attempt to convert the datatype of the result. 4957** ^For example, if the internal representation is FLOAT and a text result 4958** is requested, [sqlite3_snprintf()] is used internally to perform the 4959** conversion automatically. ^(The following table details the conversions 4960** that are applied: 4961** 4962** <blockquote> 4963** <table border="1"> 4964** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 4965** 4966** <tr><td> NULL <td> INTEGER <td> Result is 0 4967** <tr><td> NULL <td> FLOAT <td> Result is 0.0 4968** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 4969** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 4970** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 4971** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 4972** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 4973** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 4974** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 4975** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 4976** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 4977** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 4978** <tr><td> TEXT <td> BLOB <td> No change 4979** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 4980** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 4981** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed 4982** </table> 4983** </blockquote>)^ 4984** 4985** Note that when type conversions occur, pointers returned by prior 4986** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 4987** sqlite3_column_text16() may be invalidated. 4988** Type conversions and pointer invalidations might occur 4989** in the following cases: 4990** 4991** <ul> 4992** <li> The initial content is a BLOB and sqlite3_column_text() or 4993** sqlite3_column_text16() is called. A zero-terminator might 4994** need to be added to the string.</li> 4995** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 4996** sqlite3_column_text16() is called. The content must be converted 4997** to UTF-16.</li> 4998** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 4999** sqlite3_column_text() is called. The content must be converted 5000** to UTF-8.</li> 5001** </ul> 5002** 5003** ^Conversions between UTF-16be and UTF-16le are always done in place and do 5004** not invalidate a prior pointer, though of course the content of the buffer 5005** that the prior pointer references will have been modified. Other kinds 5006** of conversion are done in place when it is possible, but sometimes they 5007** are not possible and in those cases prior pointers are invalidated. 5008** 5009** The safest policy is to invoke these routines 5010** in one of the following ways: 5011** 5012** <ul> 5013** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 5014** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 5015** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 5016** </ul> 5017** 5018** In other words, you should call sqlite3_column_text(), 5019** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 5020** into the desired format, then invoke sqlite3_column_bytes() or 5021** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 5022** to sqlite3_column_text() or sqlite3_column_blob() with calls to 5023** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 5024** with calls to sqlite3_column_bytes(). 5025** 5026** ^The pointers returned are valid until a type conversion occurs as 5027** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 5028** [sqlite3_finalize()] is called. ^The memory space used to hold strings 5029** and BLOBs is freed automatically. Do not pass the pointers returned 5030** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 5031** [sqlite3_free()]. 5032** 5033** As long as the input parameters are correct, these routines will only 5034** fail if an out-of-memory error occurs during a format conversion. 5035** Only the following subset of interfaces are subject to out-of-memory 5036** errors: 5037** 5038** <ul> 5039** <li> sqlite3_column_blob() 5040** <li> sqlite3_column_text() 5041** <li> sqlite3_column_text16() 5042** <li> sqlite3_column_bytes() 5043** <li> sqlite3_column_bytes16() 5044** </ul> 5045** 5046** If an out-of-memory error occurs, then the return value from these 5047** routines is the same as if the column had contained an SQL NULL value. 5048** Valid SQL NULL returns can be distinguished from out-of-memory errors 5049** by invoking the [sqlite3_errcode()] immediately after the suspect 5050** return value is obtained and before any 5051** other SQLite interface is called on the same [database connection]. 5052*/ 5053const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 5054double sqlite3_column_double(sqlite3_stmt*, int iCol); 5055int sqlite3_column_int(sqlite3_stmt*, int iCol); 5056sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 5057const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 5058const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 5059sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 5060int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 5061int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 5062int sqlite3_column_type(sqlite3_stmt*, int iCol); 5063 5064/* 5065** CAPI3REF: Destroy A Prepared Statement Object 5066** DESTRUCTOR: sqlite3_stmt 5067** 5068** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 5069** ^If the most recent evaluation of the statement encountered no errors 5070** or if the statement is never been evaluated, then sqlite3_finalize() returns 5071** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 5072** sqlite3_finalize(S) returns the appropriate [error code] or 5073** [extended error code]. 5074** 5075** ^The sqlite3_finalize(S) routine can be called at any point during 5076** the life cycle of [prepared statement] S: 5077** before statement S is ever evaluated, after 5078** one or more calls to [sqlite3_reset()], or after any call 5079** to [sqlite3_step()] regardless of whether or not the statement has 5080** completed execution. 5081** 5082** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5083** 5084** The application must finalize every [prepared statement] in order to avoid 5085** resource leaks. It is a grievous error for the application to try to use 5086** a prepared statement after it has been finalized. Any use of a prepared 5087** statement after it has been finalized can result in undefined and 5088** undesirable behavior such as segfaults and heap corruption. 5089*/ 5090int sqlite3_finalize(sqlite3_stmt *pStmt); 5091 5092/* 5093** CAPI3REF: Reset A Prepared Statement Object 5094** METHOD: sqlite3_stmt 5095** 5096** The sqlite3_reset() function is called to reset a [prepared statement] 5097** object back to its initial state, ready to be re-executed. 5098** ^Any SQL statement variables that had values bound to them using 5099** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5100** Use [sqlite3_clear_bindings()] to reset the bindings. 5101** 5102** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5103** back to the beginning of its program. 5104** 5105** ^If the most recent call to [sqlite3_step(S)] for the 5106** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 5107** or if [sqlite3_step(S)] has never before been called on S, 5108** then [sqlite3_reset(S)] returns [SQLITE_OK]. 5109** 5110** ^If the most recent call to [sqlite3_step(S)] for the 5111** [prepared statement] S indicated an error, then 5112** [sqlite3_reset(S)] returns an appropriate [error code]. 5113** 5114** ^The [sqlite3_reset(S)] interface does not change the values 5115** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5116*/ 5117int sqlite3_reset(sqlite3_stmt *pStmt); 5118 5119/* 5120** CAPI3REF: Create Or Redefine SQL Functions 5121** KEYWORDS: {function creation routines} 5122** METHOD: sqlite3 5123** 5124** ^These functions (collectively known as "function creation routines") 5125** are used to add SQL functions or aggregates or to redefine the behavior 5126** of existing SQL functions or aggregates. The only differences between 5127** the three "sqlite3_create_function*" routines are the text encoding 5128** expected for the second parameter (the name of the function being 5129** created) and the presence or absence of a destructor callback for 5130** the application data pointer. Function sqlite3_create_window_function() 5131** is similar, but allows the user to supply the extra callback functions 5132** needed by [aggregate window functions]. 5133** 5134** ^The first parameter is the [database connection] to which the SQL 5135** function is to be added. ^If an application uses more than one database 5136** connection then application-defined SQL functions must be added 5137** to each database connection separately. 5138** 5139** ^The second parameter is the name of the SQL function to be created or 5140** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5141** representation, exclusive of the zero-terminator. ^Note that the name 5142** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5143** ^Any attempt to create a function with a longer name 5144** will result in [SQLITE_MISUSE] being returned. 5145** 5146** ^The third parameter (nArg) 5147** is the number of arguments that the SQL function or 5148** aggregate takes. ^If this parameter is -1, then the SQL function or 5149** aggregate may take any number of arguments between 0 and the limit 5150** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5151** parameter is less than -1 or greater than 127 then the behavior is 5152** undefined. 5153** 5154** ^The fourth parameter, eTextRep, specifies what 5155** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5156** its parameters. The application should set this parameter to 5157** [SQLITE_UTF16LE] if the function implementation invokes 5158** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5159** implementation invokes [sqlite3_value_text16be()] on an input, or 5160** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5161** otherwise. ^The same SQL function may be registered multiple times using 5162** different preferred text encodings, with different implementations for 5163** each encoding. 5164** ^When multiple implementations of the same function are available, SQLite 5165** will pick the one that involves the least amount of data conversion. 5166** 5167** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5168** to signal that the function will always return the same result given 5169** the same inputs within a single SQL statement. Most SQL functions are 5170** deterministic. The built-in [random()] SQL function is an example of a 5171** function that is not deterministic. The SQLite query planner is able to 5172** perform additional optimizations on deterministic functions, so use 5173** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5174** 5175** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5176** flag, which if present prevents the function from being invoked from 5177** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5178** index expressions, or the WHERE clause of partial indexes. 5179** 5180** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5181** all application-defined SQL functions that do not need to be 5182** used inside of triggers, view, CHECK constraints, or other elements of 5183** the database schema. This flags is especially recommended for SQL 5184** functions that have side effects or reveal internal application state. 5185** Without this flag, an attacker might be able to modify the schema of 5186** a database file to include invocations of the function with parameters 5187** chosen by the attacker, which the application will then execute when 5188** the database file is opened and read. 5189** 5190** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5191** function can gain access to this pointer using [sqlite3_user_data()].)^ 5192** 5193** ^The sixth, seventh and eighth parameters passed to the three 5194** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5195** pointers to C-language functions that implement the SQL function or 5196** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5197** callback only; NULL pointers must be passed as the xStep and xFinal 5198** parameters. ^An aggregate SQL function requires an implementation of xStep 5199** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5200** SQL function or aggregate, pass NULL pointers for all three function 5201** callbacks. 5202** 5203** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5204** and xInverse) passed to sqlite3_create_window_function are pointers to 5205** C-language callbacks that implement the new function. xStep and xFinal 5206** must both be non-NULL. xValue and xInverse may either both be NULL, in 5207** which case a regular aggregate function is created, or must both be 5208** non-NULL, in which case the new function may be used as either an aggregate 5209** or aggregate window function. More details regarding the implementation 5210** of aggregate window functions are 5211** [user-defined window functions|available here]. 5212** 5213** ^(If the final parameter to sqlite3_create_function_v2() or 5214** sqlite3_create_window_function() is not NULL, then it is destructor for 5215** the application data pointer. The destructor is invoked when the function 5216** is deleted, either by being overloaded or when the database connection 5217** closes.)^ ^The destructor is also invoked if the call to 5218** sqlite3_create_function_v2() fails. ^When the destructor callback is 5219** invoked, it is passed a single argument which is a copy of the application 5220** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5221** 5222** ^It is permitted to register multiple implementations of the same 5223** functions with the same name but with either differing numbers of 5224** arguments or differing preferred text encodings. ^SQLite will use 5225** the implementation that most closely matches the way in which the 5226** SQL function is used. ^A function implementation with a non-negative 5227** nArg parameter is a better match than a function implementation with 5228** a negative nArg. ^A function where the preferred text encoding 5229** matches the database encoding is a better 5230** match than a function where the encoding is different. 5231** ^A function where the encoding difference is between UTF16le and UTF16be 5232** is a closer match than a function where the encoding difference is 5233** between UTF8 and UTF16. 5234** 5235** ^Built-in functions may be overloaded by new application-defined functions. 5236** 5237** ^An application-defined function is permitted to call other 5238** SQLite interfaces. However, such calls must not 5239** close the database connection nor finalize or reset the prepared 5240** statement in which the function is running. 5241*/ 5242int sqlite3_create_function( 5243 sqlite3 *db, 5244 const char *zFunctionName, 5245 int nArg, 5246 int eTextRep, 5247 void *pApp, 5248 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5249 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5250 void (*xFinal)(sqlite3_context*) 5251); 5252int sqlite3_create_function16( 5253 sqlite3 *db, 5254 const void *zFunctionName, 5255 int nArg, 5256 int eTextRep, 5257 void *pApp, 5258 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5259 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5260 void (*xFinal)(sqlite3_context*) 5261); 5262int sqlite3_create_function_v2( 5263 sqlite3 *db, 5264 const char *zFunctionName, 5265 int nArg, 5266 int eTextRep, 5267 void *pApp, 5268 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5269 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5270 void (*xFinal)(sqlite3_context*), 5271 void(*xDestroy)(void*) 5272); 5273int sqlite3_create_window_function( 5274 sqlite3 *db, 5275 const char *zFunctionName, 5276 int nArg, 5277 int eTextRep, 5278 void *pApp, 5279 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5280 void (*xFinal)(sqlite3_context*), 5281 void (*xValue)(sqlite3_context*), 5282 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5283 void(*xDestroy)(void*) 5284); 5285 5286/* 5287** CAPI3REF: Text Encodings 5288** 5289** These constant define integer codes that represent the various 5290** text encodings supported by SQLite. 5291*/ 5292#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5293#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5294#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5295#define SQLITE_UTF16 4 /* Use native byte order */ 5296#define SQLITE_ANY 5 /* Deprecated */ 5297#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5298 5299/* 5300** CAPI3REF: Function Flags 5301** 5302** These constants may be ORed together with the 5303** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5304** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5305** [sqlite3_create_function_v2()]. 5306** 5307** <dl> 5308** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5309** The SQLITE_DETERMINISTIC flag means that the new function always gives 5310** the same output when the input parameters are the same. 5311** The [abs|abs() function] is deterministic, for example, but 5312** [randomblob|randomblob()] is not. Functions must 5313** be deterministic in order to be used in certain contexts such as 5314** with the WHERE clause of [partial indexes] or in [generated columns]. 5315** SQLite might also optimize deterministic functions by factoring them 5316** out of inner loops. 5317** </dd> 5318** 5319** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5320** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5321** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5322** schema structures such as [CHECK constraints], [DEFAULT clauses], 5323** [expression indexes], [partial indexes], or [generated columns]. 5324** The SQLITE_DIRECTONLY flags is a security feature which is recommended 5325** for all [application-defined SQL functions], and especially for functions 5326** that have side-effects or that could potentially leak sensitive 5327** information. 5328** </dd> 5329** 5330** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5331** The SQLITE_INNOCUOUS flag means that the function is unlikely 5332** to cause problems even if misused. An innocuous function should have 5333** no side effects and should not depend on any values other than its 5334** input parameters. The [abs|abs() function] is an example of an 5335** innocuous function. 5336** The [load_extension() SQL function] is not innocuous because of its 5337** side effects. 5338** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5339** exactly the same. The [random|random() function] is an example of a 5340** function that is innocuous but not deterministic. 5341** <p>Some heightened security settings 5342** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5343** disable the use of SQL functions inside views and triggers and in 5344** schema structures such as [CHECK constraints], [DEFAULT clauses], 5345** [expression indexes], [partial indexes], and [generated columns] unless 5346** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5347** are innocuous. Developers are advised to avoid using the 5348** SQLITE_INNOCUOUS flag for application-defined functions unless the 5349** function has been carefully audited and found to be free of potentially 5350** security-adverse side-effects and information-leaks. 5351** </dd> 5352** 5353** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5354** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call 5355** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5356** Specifying this flag makes no difference for scalar or aggregate user 5357** functions. However, if it is not specified for a user-defined window 5358** function, then any sub-types belonging to arguments passed to the window 5359** function may be discarded before the window function is called (i.e. 5360** sqlite3_value_subtype() will always return 0). 5361** </dd> 5362** </dl> 5363*/ 5364#define SQLITE_DETERMINISTIC 0x000000800 5365#define SQLITE_DIRECTONLY 0x000080000 5366#define SQLITE_SUBTYPE 0x000100000 5367#define SQLITE_INNOCUOUS 0x000200000 5368 5369/* 5370** CAPI3REF: Deprecated Functions 5371** DEPRECATED 5372** 5373** These functions are [deprecated]. In order to maintain 5374** backwards compatibility with older code, these functions continue 5375** to be supported. However, new applications should avoid 5376** the use of these functions. To encourage programmers to avoid 5377** these functions, we will not explain what they do. 5378*/ 5379#ifndef SQLITE_OMIT_DEPRECATED 5380SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5381SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5382SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5383SQLITE_DEPRECATED int sqlite3_global_recover(void); 5384SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5385SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5386 void*,sqlite3_int64); 5387#endif 5388 5389/* 5390** CAPI3REF: Obtaining SQL Values 5391** METHOD: sqlite3_value 5392** 5393** <b>Summary:</b> 5394** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5395** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5396** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5397** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5398** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5399** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5400** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5401** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5402** the native byteorder 5403** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5404** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5405** <tr><td> <td> <td> 5406** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5407** or a UTF-8 TEXT in bytes 5408** <tr><td><b>sqlite3_value_bytes16 </b> 5409** <td>→ <td>Size of UTF-16 5410** TEXT in bytes 5411** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5412** datatype of the value 5413** <tr><td><b>sqlite3_value_numeric_type </b> 5414** <td>→ <td>Best numeric datatype of the value 5415** <tr><td><b>sqlite3_value_nochange </b> 5416** <td>→ <td>True if the column is unchanged in an UPDATE 5417** against a virtual table. 5418** <tr><td><b>sqlite3_value_frombind </b> 5419** <td>→ <td>True if value originated from a [bound parameter] 5420** </table></blockquote> 5421** 5422** <b>Details:</b> 5423** 5424** These routines extract type, size, and content information from 5425** [protected sqlite3_value] objects. Protected sqlite3_value objects 5426** are used to pass parameter information into the functions that 5427** implement [application-defined SQL functions] and [virtual tables]. 5428** 5429** These routines work only with [protected sqlite3_value] objects. 5430** Any attempt to use these routines on an [unprotected sqlite3_value] 5431** is not threadsafe. 5432** 5433** ^These routines work just like the corresponding [column access functions] 5434** except that these routines take a single [protected sqlite3_value] object 5435** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5436** 5437** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5438** in the native byte-order of the host machine. ^The 5439** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5440** extract UTF-16 strings as big-endian and little-endian respectively. 5441** 5442** ^If [sqlite3_value] object V was initialized 5443** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5444** and if X and Y are strings that compare equal according to strcmp(X,Y), 5445** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5446** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5447** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5448** 5449** ^(The sqlite3_value_type(V) interface returns the 5450** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5451** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5452** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5453** Other interfaces might change the datatype for an sqlite3_value object. 5454** For example, if the datatype is initially SQLITE_INTEGER and 5455** sqlite3_value_text(V) is called to extract a text value for that 5456** integer, then subsequent calls to sqlite3_value_type(V) might return 5457** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5458** occurs is undefined and may change from one release of SQLite to the next. 5459** 5460** ^(The sqlite3_value_numeric_type() interface attempts to apply 5461** numeric affinity to the value. This means that an attempt is 5462** made to convert the value to an integer or floating point. If 5463** such a conversion is possible without loss of information (in other 5464** words, if the value is a string that looks like a number) 5465** then the conversion is performed. Otherwise no conversion occurs. 5466** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5467** 5468** ^Within the [xUpdate] method of a [virtual table], the 5469** sqlite3_value_nochange(X) interface returns true if and only if 5470** the column corresponding to X is unchanged by the UPDATE operation 5471** that the xUpdate method call was invoked to implement and if 5472** and the prior [xColumn] method call that was invoked to extracted 5473** the value for that column returned without setting a result (probably 5474** because it queried [sqlite3_vtab_nochange()] and found that the column 5475** was unchanging). ^Within an [xUpdate] method, any value for which 5476** sqlite3_value_nochange(X) is true will in all other respects appear 5477** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5478** than within an [xUpdate] method call for an UPDATE statement, then 5479** the return value is arbitrary and meaningless. 5480** 5481** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5482** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5483** interfaces. ^If X comes from an SQL literal value, or a table column, 5484** or an expression, then sqlite3_value_frombind(X) returns zero. 5485** 5486** Please pay particular attention to the fact that the pointer returned 5487** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5488** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5489** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5490** or [sqlite3_value_text16()]. 5491** 5492** These routines must be called from the same thread as 5493** the SQL function that supplied the [sqlite3_value*] parameters. 5494** 5495** As long as the input parameter is correct, these routines can only 5496** fail if an out-of-memory error occurs during a format conversion. 5497** Only the following subset of interfaces are subject to out-of-memory 5498** errors: 5499** 5500** <ul> 5501** <li> sqlite3_value_blob() 5502** <li> sqlite3_value_text() 5503** <li> sqlite3_value_text16() 5504** <li> sqlite3_value_text16le() 5505** <li> sqlite3_value_text16be() 5506** <li> sqlite3_value_bytes() 5507** <li> sqlite3_value_bytes16() 5508** </ul> 5509** 5510** If an out-of-memory error occurs, then the return value from these 5511** routines is the same as if the column had contained an SQL NULL value. 5512** Valid SQL NULL returns can be distinguished from out-of-memory errors 5513** by invoking the [sqlite3_errcode()] immediately after the suspect 5514** return value is obtained and before any 5515** other SQLite interface is called on the same [database connection]. 5516*/ 5517const void *sqlite3_value_blob(sqlite3_value*); 5518double sqlite3_value_double(sqlite3_value*); 5519int sqlite3_value_int(sqlite3_value*); 5520sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5521void *sqlite3_value_pointer(sqlite3_value*, const char*); 5522const unsigned char *sqlite3_value_text(sqlite3_value*); 5523const void *sqlite3_value_text16(sqlite3_value*); 5524const void *sqlite3_value_text16le(sqlite3_value*); 5525const void *sqlite3_value_text16be(sqlite3_value*); 5526int sqlite3_value_bytes(sqlite3_value*); 5527int sqlite3_value_bytes16(sqlite3_value*); 5528int sqlite3_value_type(sqlite3_value*); 5529int sqlite3_value_numeric_type(sqlite3_value*); 5530int sqlite3_value_nochange(sqlite3_value*); 5531int sqlite3_value_frombind(sqlite3_value*); 5532 5533/* 5534** CAPI3REF: Finding The Subtype Of SQL Values 5535** METHOD: sqlite3_value 5536** 5537** The sqlite3_value_subtype(V) function returns the subtype for 5538** an [application-defined SQL function] argument V. The subtype 5539** information can be used to pass a limited amount of context from 5540** one SQL function to another. Use the [sqlite3_result_subtype()] 5541** routine to set the subtype for the return value of an SQL function. 5542*/ 5543unsigned int sqlite3_value_subtype(sqlite3_value*); 5544 5545/* 5546** CAPI3REF: Copy And Free SQL Values 5547** METHOD: sqlite3_value 5548** 5549** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5550** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5551** is a [protected sqlite3_value] object even if the input is not. 5552** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5553** memory allocation fails. 5554** 5555** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5556** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5557** then sqlite3_value_free(V) is a harmless no-op. 5558*/ 5559sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5560void sqlite3_value_free(sqlite3_value*); 5561 5562/* 5563** CAPI3REF: Obtain Aggregate Function Context 5564** METHOD: sqlite3_context 5565** 5566** Implementations of aggregate SQL functions use this 5567** routine to allocate memory for storing their state. 5568** 5569** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5570** for a particular aggregate function, SQLite allocates 5571** N bytes of memory, zeroes out that memory, and returns a pointer 5572** to the new memory. ^On second and subsequent calls to 5573** sqlite3_aggregate_context() for the same aggregate function instance, 5574** the same buffer is returned. Sqlite3_aggregate_context() is normally 5575** called once for each invocation of the xStep callback and then one 5576** last time when the xFinal callback is invoked. ^(When no rows match 5577** an aggregate query, the xStep() callback of the aggregate function 5578** implementation is never called and xFinal() is called exactly once. 5579** In those cases, sqlite3_aggregate_context() might be called for the 5580** first time from within xFinal().)^ 5581** 5582** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5583** when first called if N is less than or equal to zero or if a memory 5584** allocate error occurs. 5585** 5586** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5587** determined by the N parameter on first successful call. Changing the 5588** value of N in any subsequent call to sqlite3_aggregate_context() within 5589** the same aggregate function instance will not resize the memory 5590** allocation.)^ Within the xFinal callback, it is customary to set 5591** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5592** pointless memory allocations occur. 5593** 5594** ^SQLite automatically frees the memory allocated by 5595** sqlite3_aggregate_context() when the aggregate query concludes. 5596** 5597** The first parameter must be a copy of the 5598** [sqlite3_context | SQL function context] that is the first parameter 5599** to the xStep or xFinal callback routine that implements the aggregate 5600** function. 5601** 5602** This routine must be called from the same thread in which 5603** the aggregate SQL function is running. 5604*/ 5605void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5606 5607/* 5608** CAPI3REF: User Data For Functions 5609** METHOD: sqlite3_context 5610** 5611** ^The sqlite3_user_data() interface returns a copy of 5612** the pointer that was the pUserData parameter (the 5th parameter) 5613** of the [sqlite3_create_function()] 5614** and [sqlite3_create_function16()] routines that originally 5615** registered the application defined function. 5616** 5617** This routine must be called from the same thread in which 5618** the application-defined function is running. 5619*/ 5620void *sqlite3_user_data(sqlite3_context*); 5621 5622/* 5623** CAPI3REF: Database Connection For Functions 5624** METHOD: sqlite3_context 5625** 5626** ^The sqlite3_context_db_handle() interface returns a copy of 5627** the pointer to the [database connection] (the 1st parameter) 5628** of the [sqlite3_create_function()] 5629** and [sqlite3_create_function16()] routines that originally 5630** registered the application defined function. 5631*/ 5632sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5633 5634/* 5635** CAPI3REF: Function Auxiliary Data 5636** METHOD: sqlite3_context 5637** 5638** These functions may be used by (non-aggregate) SQL functions to 5639** associate metadata with argument values. If the same value is passed to 5640** multiple invocations of the same SQL function during query execution, under 5641** some circumstances the associated metadata may be preserved. An example 5642** of where this might be useful is in a regular-expression matching 5643** function. The compiled version of the regular expression can be stored as 5644** metadata associated with the pattern string. 5645** Then as long as the pattern string remains the same, 5646** the compiled regular expression can be reused on multiple 5647** invocations of the same function. 5648** 5649** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata 5650** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5651** value to the application-defined function. ^N is zero for the left-most 5652** function argument. ^If there is no metadata 5653** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5654** returns a NULL pointer. 5655** 5656** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 5657** argument of the application-defined function. ^Subsequent 5658** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5659** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 5660** NULL if the metadata has been discarded. 5661** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5662** SQLite will invoke the destructor function X with parameter P exactly 5663** once, when the metadata is discarded. 5664** SQLite is free to discard the metadata at any time, including: <ul> 5665** <li> ^(when the corresponding function parameter changes)^, or 5666** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5667** SQL statement)^, or 5668** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5669** parameter)^, or 5670** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5671** allocation error occurs.)^ </ul> 5672** 5673** Note the last bullet in particular. The destructor X in 5674** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5675** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5676** should be called near the end of the function implementation and the 5677** function implementation should not make any use of P after 5678** sqlite3_set_auxdata() has been called. 5679** 5680** ^(In practice, metadata is preserved between function calls for 5681** function parameters that are compile-time constants, including literal 5682** values and [parameters] and expressions composed from the same.)^ 5683** 5684** The value of the N parameter to these interfaces should be non-negative. 5685** Future enhancements may make use of negative N values to define new 5686** kinds of function caching behavior. 5687** 5688** These routines must be called from the same thread in which 5689** the SQL function is running. 5690*/ 5691void *sqlite3_get_auxdata(sqlite3_context*, int N); 5692void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5693 5694 5695/* 5696** CAPI3REF: Constants Defining Special Destructor Behavior 5697** 5698** These are special values for the destructor that is passed in as the 5699** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 5700** argument is SQLITE_STATIC, it means that the content pointer is constant 5701** and will never change. It does not need to be destroyed. ^The 5702** SQLITE_TRANSIENT value means that the content will likely change in 5703** the near future and that SQLite should make its own private copy of 5704** the content before returning. 5705** 5706** The typedef is necessary to work around problems in certain 5707** C++ compilers. 5708*/ 5709typedef void (*sqlite3_destructor_type)(void*); 5710#define SQLITE_STATIC ((sqlite3_destructor_type)0) 5711#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 5712 5713/* 5714** CAPI3REF: Setting The Result Of An SQL Function 5715** METHOD: sqlite3_context 5716** 5717** These routines are used by the xFunc or xFinal callbacks that 5718** implement SQL functions and aggregates. See 5719** [sqlite3_create_function()] and [sqlite3_create_function16()] 5720** for additional information. 5721** 5722** These functions work very much like the [parameter binding] family of 5723** functions used to bind values to host parameters in prepared statements. 5724** Refer to the [SQL parameter] documentation for additional information. 5725** 5726** ^The sqlite3_result_blob() interface sets the result from 5727** an application-defined function to be the BLOB whose content is pointed 5728** to by the second parameter and which is N bytes long where N is the 5729** third parameter. 5730** 5731** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 5732** interfaces set the result of the application-defined function to be 5733** a BLOB containing all zero bytes and N bytes in size. 5734** 5735** ^The sqlite3_result_double() interface sets the result from 5736** an application-defined function to be a floating point value specified 5737** by its 2nd argument. 5738** 5739** ^The sqlite3_result_error() and sqlite3_result_error16() functions 5740** cause the implemented SQL function to throw an exception. 5741** ^SQLite uses the string pointed to by the 5742** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 5743** as the text of an error message. ^SQLite interprets the error 5744** message string from sqlite3_result_error() as UTF-8. ^SQLite 5745** interprets the string from sqlite3_result_error16() as UTF-16 using 5746** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 5747** ^If the third parameter to sqlite3_result_error() 5748** or sqlite3_result_error16() is negative then SQLite takes as the error 5749** message all text up through the first zero character. 5750** ^If the third parameter to sqlite3_result_error() or 5751** sqlite3_result_error16() is non-negative then SQLite takes that many 5752** bytes (not characters) from the 2nd parameter as the error message. 5753** ^The sqlite3_result_error() and sqlite3_result_error16() 5754** routines make a private copy of the error message text before 5755** they return. Hence, the calling function can deallocate or 5756** modify the text after they return without harm. 5757** ^The sqlite3_result_error_code() function changes the error code 5758** returned by SQLite as a result of an error in a function. ^By default, 5759** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 5760** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 5761** 5762** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 5763** error indicating that a string or BLOB is too long to represent. 5764** 5765** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 5766** error indicating that a memory allocation failed. 5767** 5768** ^The sqlite3_result_int() interface sets the return value 5769** of the application-defined function to be the 32-bit signed integer 5770** value given in the 2nd argument. 5771** ^The sqlite3_result_int64() interface sets the return value 5772** of the application-defined function to be the 64-bit signed integer 5773** value given in the 2nd argument. 5774** 5775** ^The sqlite3_result_null() interface sets the return value 5776** of the application-defined function to be NULL. 5777** 5778** ^The sqlite3_result_text(), sqlite3_result_text16(), 5779** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 5780** set the return value of the application-defined function to be 5781** a text string which is represented as UTF-8, UTF-16 native byte order, 5782** UTF-16 little endian, or UTF-16 big endian, respectively. 5783** ^The sqlite3_result_text64() interface sets the return value of an 5784** application-defined function to be a text string in an encoding 5785** specified by the fifth (and last) parameter, which must be one 5786** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 5787** ^SQLite takes the text result from the application from 5788** the 2nd parameter of the sqlite3_result_text* interfaces. 5789** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5790** is negative, then SQLite takes result text from the 2nd parameter 5791** through the first zero character. 5792** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5793** is non-negative, then as many bytes (not characters) of the text 5794** pointed to by the 2nd parameter are taken as the application-defined 5795** function result. If the 3rd parameter is non-negative, then it 5796** must be the byte offset into the string where the NUL terminator would 5797** appear if the string where NUL terminated. If any NUL characters occur 5798** in the string at a byte offset that is less than the value of the 3rd 5799** parameter, then the resulting string will contain embedded NULs and the 5800** result of expressions operating on strings with embedded NULs is undefined. 5801** ^If the 4th parameter to the sqlite3_result_text* interfaces 5802** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 5803** function as the destructor on the text or BLOB result when it has 5804** finished using that result. 5805** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 5806** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 5807** assumes that the text or BLOB result is in constant space and does not 5808** copy the content of the parameter nor call a destructor on the content 5809** when it has finished using that result. 5810** ^If the 4th parameter to the sqlite3_result_text* interfaces 5811** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 5812** then SQLite makes a copy of the result into space obtained 5813** from [sqlite3_malloc()] before it returns. 5814** 5815** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 5816** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 5817** when the encoding is not UTF8, if the input UTF16 begins with a 5818** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 5819** string and the rest of the string is interpreted according to the 5820** byte-order specified by the BOM. ^The byte-order specified by 5821** the BOM at the beginning of the text overrides the byte-order 5822** specified by the interface procedure. ^So, for example, if 5823** sqlite3_result_text16le() is invoked with text that begins 5824** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 5825** first two bytes of input are skipped and the remaining input 5826** is interpreted as UTF16BE text. 5827** 5828** ^For UTF16 input text to the sqlite3_result_text16(), 5829** sqlite3_result_text16be(), sqlite3_result_text16le(), and 5830** sqlite3_result_text64() routines, if the text contains invalid 5831** UTF16 characters, the invalid characters might be converted 5832** into the unicode replacement character, U+FFFD. 5833** 5834** ^The sqlite3_result_value() interface sets the result of 5835** the application-defined function to be a copy of the 5836** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 5837** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 5838** so that the [sqlite3_value] specified in the parameter may change or 5839** be deallocated after sqlite3_result_value() returns without harm. 5840** ^A [protected sqlite3_value] object may always be used where an 5841** [unprotected sqlite3_value] object is required, so either 5842** kind of [sqlite3_value] object can be used with this interface. 5843** 5844** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 5845** SQL NULL value, just like [sqlite3_result_null(C)], except that it 5846** also associates the host-language pointer P or type T with that 5847** NULL value such that the pointer can be retrieved within an 5848** [application-defined SQL function] using [sqlite3_value_pointer()]. 5849** ^If the D parameter is not NULL, then it is a pointer to a destructor 5850** for the P parameter. ^SQLite invokes D with P as its only argument 5851** when SQLite is finished with P. The T parameter should be a static 5852** string and preferably a string literal. The sqlite3_result_pointer() 5853** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5854** 5855** If these routines are called from within the different thread 5856** than the one containing the application-defined function that received 5857** the [sqlite3_context] pointer, the results are undefined. 5858*/ 5859void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 5860void sqlite3_result_blob64(sqlite3_context*,const void*, 5861 sqlite3_uint64,void(*)(void*)); 5862void sqlite3_result_double(sqlite3_context*, double); 5863void sqlite3_result_error(sqlite3_context*, const char*, int); 5864void sqlite3_result_error16(sqlite3_context*, const void*, int); 5865void sqlite3_result_error_toobig(sqlite3_context*); 5866void sqlite3_result_error_nomem(sqlite3_context*); 5867void sqlite3_result_error_code(sqlite3_context*, int); 5868void sqlite3_result_int(sqlite3_context*, int); 5869void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 5870void sqlite3_result_null(sqlite3_context*); 5871void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 5872void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 5873 void(*)(void*), unsigned char encoding); 5874void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 5875void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 5876void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 5877void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 5878void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 5879void sqlite3_result_zeroblob(sqlite3_context*, int n); 5880int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 5881 5882 5883/* 5884** CAPI3REF: Setting The Subtype Of An SQL Function 5885** METHOD: sqlite3_context 5886** 5887** The sqlite3_result_subtype(C,T) function causes the subtype of 5888** the result from the [application-defined SQL function] with 5889** [sqlite3_context] C to be the value T. Only the lower 8 bits 5890** of the subtype T are preserved in current versions of SQLite; 5891** higher order bits are discarded. 5892** The number of subtype bytes preserved by SQLite might increase 5893** in future releases of SQLite. 5894*/ 5895void sqlite3_result_subtype(sqlite3_context*,unsigned int); 5896 5897/* 5898** CAPI3REF: Define New Collating Sequences 5899** METHOD: sqlite3 5900** 5901** ^These functions add, remove, or modify a [collation] associated 5902** with the [database connection] specified as the first argument. 5903** 5904** ^The name of the collation is a UTF-8 string 5905** for sqlite3_create_collation() and sqlite3_create_collation_v2() 5906** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 5907** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 5908** considered to be the same name. 5909** 5910** ^(The third argument (eTextRep) must be one of the constants: 5911** <ul> 5912** <li> [SQLITE_UTF8], 5913** <li> [SQLITE_UTF16LE], 5914** <li> [SQLITE_UTF16BE], 5915** <li> [SQLITE_UTF16], or 5916** <li> [SQLITE_UTF16_ALIGNED]. 5917** </ul>)^ 5918** ^The eTextRep argument determines the encoding of strings passed 5919** to the collating function callback, xCompare. 5920** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 5921** force strings to be UTF16 with native byte order. 5922** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 5923** on an even byte address. 5924** 5925** ^The fourth argument, pArg, is an application data pointer that is passed 5926** through as the first argument to the collating function callback. 5927** 5928** ^The fifth argument, xCompare, is a pointer to the collating function. 5929** ^Multiple collating functions can be registered using the same name but 5930** with different eTextRep parameters and SQLite will use whichever 5931** function requires the least amount of data transformation. 5932** ^If the xCompare argument is NULL then the collating function is 5933** deleted. ^When all collating functions having the same name are deleted, 5934** that collation is no longer usable. 5935** 5936** ^The collating function callback is invoked with a copy of the pArg 5937** application data pointer and with two strings in the encoding specified 5938** by the eTextRep argument. The two integer parameters to the collating 5939** function callback are the length of the two strings, in bytes. The collating 5940** function must return an integer that is negative, zero, or positive 5941** if the first string is less than, equal to, or greater than the second, 5942** respectively. A collating function must always return the same answer 5943** given the same inputs. If two or more collating functions are registered 5944** to the same collation name (using different eTextRep values) then all 5945** must give an equivalent answer when invoked with equivalent strings. 5946** The collating function must obey the following properties for all 5947** strings A, B, and C: 5948** 5949** <ol> 5950** <li> If A==B then B==A. 5951** <li> If A==B and B==C then A==C. 5952** <li> If A<B THEN B>A. 5953** <li> If A<B and B<C then A<C. 5954** </ol> 5955** 5956** If a collating function fails any of the above constraints and that 5957** collating function is registered and used, then the behavior of SQLite 5958** is undefined. 5959** 5960** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 5961** with the addition that the xDestroy callback is invoked on pArg when 5962** the collating function is deleted. 5963** ^Collating functions are deleted when they are overridden by later 5964** calls to the collation creation functions or when the 5965** [database connection] is closed using [sqlite3_close()]. 5966** 5967** ^The xDestroy callback is <u>not</u> called if the 5968** sqlite3_create_collation_v2() function fails. Applications that invoke 5969** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 5970** check the return code and dispose of the application data pointer 5971** themselves rather than expecting SQLite to deal with it for them. 5972** This is different from every other SQLite interface. The inconsistency 5973** is unfortunate but cannot be changed without breaking backwards 5974** compatibility. 5975** 5976** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 5977*/ 5978int sqlite3_create_collation( 5979 sqlite3*, 5980 const char *zName, 5981 int eTextRep, 5982 void *pArg, 5983 int(*xCompare)(void*,int,const void*,int,const void*) 5984); 5985int sqlite3_create_collation_v2( 5986 sqlite3*, 5987 const char *zName, 5988 int eTextRep, 5989 void *pArg, 5990 int(*xCompare)(void*,int,const void*,int,const void*), 5991 void(*xDestroy)(void*) 5992); 5993int sqlite3_create_collation16( 5994 sqlite3*, 5995 const void *zName, 5996 int eTextRep, 5997 void *pArg, 5998 int(*xCompare)(void*,int,const void*,int,const void*) 5999); 6000 6001/* 6002** CAPI3REF: Collation Needed Callbacks 6003** METHOD: sqlite3 6004** 6005** ^To avoid having to register all collation sequences before a database 6006** can be used, a single callback function may be registered with the 6007** [database connection] to be invoked whenever an undefined collation 6008** sequence is required. 6009** 6010** ^If the function is registered using the sqlite3_collation_needed() API, 6011** then it is passed the names of undefined collation sequences as strings 6012** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 6013** the names are passed as UTF-16 in machine native byte order. 6014** ^A call to either function replaces the existing collation-needed callback. 6015** 6016** ^(When the callback is invoked, the first argument passed is a copy 6017** of the second argument to sqlite3_collation_needed() or 6018** sqlite3_collation_needed16(). The second argument is the database 6019** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 6020** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 6021** sequence function required. The fourth parameter is the name of the 6022** required collation sequence.)^ 6023** 6024** The callback function should register the desired collation using 6025** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 6026** [sqlite3_create_collation_v2()]. 6027*/ 6028int sqlite3_collation_needed( 6029 sqlite3*, 6030 void*, 6031 void(*)(void*,sqlite3*,int eTextRep,const char*) 6032); 6033int sqlite3_collation_needed16( 6034 sqlite3*, 6035 void*, 6036 void(*)(void*,sqlite3*,int eTextRep,const void*) 6037); 6038 6039#ifdef SQLITE_ENABLE_CEROD 6040/* 6041** Specify the activation key for a CEROD database. Unless 6042** activated, none of the CEROD routines will work. 6043*/ 6044void sqlite3_activate_cerod( 6045 const char *zPassPhrase /* Activation phrase */ 6046); 6047#endif 6048 6049/* 6050** CAPI3REF: Suspend Execution For A Short Time 6051** 6052** The sqlite3_sleep() function causes the current thread to suspend execution 6053** for at least a number of milliseconds specified in its parameter. 6054** 6055** If the operating system does not support sleep requests with 6056** millisecond time resolution, then the time will be rounded up to 6057** the nearest second. The number of milliseconds of sleep actually 6058** requested from the operating system is returned. 6059** 6060** ^SQLite implements this interface by calling the xSleep() 6061** method of the default [sqlite3_vfs] object. If the xSleep() method 6062** of the default VFS is not implemented correctly, or not implemented at 6063** all, then the behavior of sqlite3_sleep() may deviate from the description 6064** in the previous paragraphs. 6065*/ 6066int sqlite3_sleep(int); 6067 6068/* 6069** CAPI3REF: Name Of The Folder Holding Temporary Files 6070** 6071** ^(If this global variable is made to point to a string which is 6072** the name of a folder (a.k.a. directory), then all temporary files 6073** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6074** will be placed in that directory.)^ ^If this variable 6075** is a NULL pointer, then SQLite performs a search for an appropriate 6076** temporary file directory. 6077** 6078** Applications are strongly discouraged from using this global variable. 6079** It is required to set a temporary folder on Windows Runtime (WinRT). 6080** But for all other platforms, it is highly recommended that applications 6081** neither read nor write this variable. This global variable is a relic 6082** that exists for backwards compatibility of legacy applications and should 6083** be avoided in new projects. 6084** 6085** It is not safe to read or modify this variable in more than one 6086** thread at a time. It is not safe to read or modify this variable 6087** if a [database connection] is being used at the same time in a separate 6088** thread. 6089** It is intended that this variable be set once 6090** as part of process initialization and before any SQLite interface 6091** routines have been called and that this variable remain unchanged 6092** thereafter. 6093** 6094** ^The [temp_store_directory pragma] may modify this variable and cause 6095** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6096** the [temp_store_directory pragma] always assumes that any string 6097** that this variable points to is held in memory obtained from 6098** [sqlite3_malloc] and the pragma may attempt to free that memory 6099** using [sqlite3_free]. 6100** Hence, if this variable is modified directly, either it should be 6101** made NULL or made to point to memory obtained from [sqlite3_malloc] 6102** or else the use of the [temp_store_directory pragma] should be avoided. 6103** Except when requested by the [temp_store_directory pragma], SQLite 6104** does not free the memory that sqlite3_temp_directory points to. If 6105** the application wants that memory to be freed, it must do 6106** so itself, taking care to only do so after all [database connection] 6107** objects have been destroyed. 6108** 6109** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6110** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6111** features that require the use of temporary files may fail. Here is an 6112** example of how to do this using C++ with the Windows Runtime: 6113** 6114** <blockquote><pre> 6115** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6116** TemporaryFolder->Path->Data(); 6117** char zPathBuf[MAX_PATH + 1]; 6118** memset(zPathBuf, 0, sizeof(zPathBuf)); 6119** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6120** NULL, NULL); 6121** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6122** </pre></blockquote> 6123*/ 6124SQLITE_EXTERN char *sqlite3_temp_directory; 6125 6126/* 6127** CAPI3REF: Name Of The Folder Holding Database Files 6128** 6129** ^(If this global variable is made to point to a string which is 6130** the name of a folder (a.k.a. directory), then all database files 6131** specified with a relative pathname and created or accessed by 6132** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6133** to be relative to that directory.)^ ^If this variable is a NULL 6134** pointer, then SQLite assumes that all database files specified 6135** with a relative pathname are relative to the current directory 6136** for the process. Only the windows VFS makes use of this global 6137** variable; it is ignored by the unix VFS. 6138** 6139** Changing the value of this variable while a database connection is 6140** open can result in a corrupt database. 6141** 6142** It is not safe to read or modify this variable in more than one 6143** thread at a time. It is not safe to read or modify this variable 6144** if a [database connection] is being used at the same time in a separate 6145** thread. 6146** It is intended that this variable be set once 6147** as part of process initialization and before any SQLite interface 6148** routines have been called and that this variable remain unchanged 6149** thereafter. 6150** 6151** ^The [data_store_directory pragma] may modify this variable and cause 6152** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6153** the [data_store_directory pragma] always assumes that any string 6154** that this variable points to is held in memory obtained from 6155** [sqlite3_malloc] and the pragma may attempt to free that memory 6156** using [sqlite3_free]. 6157** Hence, if this variable is modified directly, either it should be 6158** made NULL or made to point to memory obtained from [sqlite3_malloc] 6159** or else the use of the [data_store_directory pragma] should be avoided. 6160*/ 6161SQLITE_EXTERN char *sqlite3_data_directory; 6162 6163/* 6164** CAPI3REF: Win32 Specific Interface 6165** 6166** These interfaces are available only on Windows. The 6167** [sqlite3_win32_set_directory] interface is used to set the value associated 6168** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6169** zValue, depending on the value of the type parameter. The zValue parameter 6170** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6171** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6172** prior to being used. The [sqlite3_win32_set_directory] interface returns 6173** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6174** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6175** [sqlite3_data_directory] variable is intended to act as a replacement for 6176** the current directory on the sub-platforms of Win32 where that concept is 6177** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6178** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6179** sqlite3_win32_set_directory interface except the string parameter must be 6180** UTF-8 or UTF-16, respectively. 6181*/ 6182int sqlite3_win32_set_directory( 6183 unsigned long type, /* Identifier for directory being set or reset */ 6184 void *zValue /* New value for directory being set or reset */ 6185); 6186int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6187int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6188 6189/* 6190** CAPI3REF: Win32 Directory Types 6191** 6192** These macros are only available on Windows. They define the allowed values 6193** for the type argument to the [sqlite3_win32_set_directory] interface. 6194*/ 6195#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6196#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6197 6198/* 6199** CAPI3REF: Test For Auto-Commit Mode 6200** KEYWORDS: {autocommit mode} 6201** METHOD: sqlite3 6202** 6203** ^The sqlite3_get_autocommit() interface returns non-zero or 6204** zero if the given database connection is or is not in autocommit mode, 6205** respectively. ^Autocommit mode is on by default. 6206** ^Autocommit mode is disabled by a [BEGIN] statement. 6207** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6208** 6209** If certain kinds of errors occur on a statement within a multi-statement 6210** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6211** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6212** transaction might be rolled back automatically. The only way to 6213** find out whether SQLite automatically rolled back the transaction after 6214** an error is to use this function. 6215** 6216** If another thread changes the autocommit status of the database 6217** connection while this routine is running, then the return value 6218** is undefined. 6219*/ 6220int sqlite3_get_autocommit(sqlite3*); 6221 6222/* 6223** CAPI3REF: Find The Database Handle Of A Prepared Statement 6224** METHOD: sqlite3_stmt 6225** 6226** ^The sqlite3_db_handle interface returns the [database connection] handle 6227** to which a [prepared statement] belongs. ^The [database connection] 6228** returned by sqlite3_db_handle is the same [database connection] 6229** that was the first argument 6230** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6231** create the statement in the first place. 6232*/ 6233sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6234 6235/* 6236** CAPI3REF: Return The Filename For A Database Connection 6237** METHOD: sqlite3 6238** 6239** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6240** associated with database N of connection D. 6241** ^If there is no attached database N on the database 6242** connection D, or if database N is a temporary or in-memory database, then 6243** this function will return either a NULL pointer or an empty string. 6244** 6245** ^The string value returned by this routine is owned and managed by 6246** the database connection. ^The value will be valid until the database N 6247** is [DETACH]-ed or until the database connection closes. 6248** 6249** ^The filename returned by this function is the output of the 6250** xFullPathname method of the [VFS]. ^In other words, the filename 6251** will be an absolute pathname, even if the filename used 6252** to open the database originally was a URI or relative pathname. 6253** 6254** If the filename pointer returned by this routine is not NULL, then it 6255** can be used as the filename input parameter to these routines: 6256** <ul> 6257** <li> [sqlite3_uri_parameter()] 6258** <li> [sqlite3_uri_boolean()] 6259** <li> [sqlite3_uri_int64()] 6260** <li> [sqlite3_filename_database()] 6261** <li> [sqlite3_filename_journal()] 6262** <li> [sqlite3_filename_wal()] 6263** </ul> 6264*/ 6265const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6266 6267/* 6268** CAPI3REF: Determine if a database is read-only 6269** METHOD: sqlite3 6270** 6271** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6272** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6273** the name of a database on connection D. 6274*/ 6275int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6276 6277/* 6278** CAPI3REF: Determine the transaction state of a database 6279** METHOD: sqlite3 6280** 6281** ^The sqlite3_txn_state(D,S) interface returns the current 6282** [transaction state] of schema S in database connection D. ^If S is NULL, 6283** then the highest transaction state of any schema on database connection D 6284** is returned. Transaction states are (in order of lowest to highest): 6285** <ol> 6286** <li value="0"> SQLITE_TXN_NONE 6287** <li value="1"> SQLITE_TXN_READ 6288** <li value="2"> SQLITE_TXN_WRITE 6289** </ol> 6290** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 6291** a valid schema, then -1 is returned. 6292*/ 6293int sqlite3_txn_state(sqlite3*,const char *zSchema); 6294 6295/* 6296** CAPI3REF: Allowed return values from [sqlite3_txn_state()] 6297** KEYWORDS: {transaction state} 6298** 6299** These constants define the current transaction state of a database file. 6300** ^The [sqlite3_txn_state(D,S)] interface returns one of these 6301** constants in order to describe the transaction state of schema S 6302** in [database connection] D. 6303** 6304** <dl> 6305** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 6306** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 6307** pending.</dd> 6308** 6309** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 6310** <dd>The SQLITE_TXN_READ state means that the database is currently 6311** in a read transaction. Content has been read from the database file 6312** but nothing in the database file has changed. The transaction state 6313** will advanced to SQLITE_TXN_WRITE if any changes occur and there are 6314** no other conflicting concurrent write transactions. The transaction 6315** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 6316** [COMMIT].</dd> 6317** 6318** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 6319** <dd>The SQLITE_TXN_WRITE state means that the database is currently 6320** in a write transaction. Content has been written to the database file 6321** but has not yet committed. The transaction state will change to 6322** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 6323*/ 6324#define SQLITE_TXN_NONE 0 6325#define SQLITE_TXN_READ 1 6326#define SQLITE_TXN_WRITE 2 6327 6328/* 6329** CAPI3REF: Find the next prepared statement 6330** METHOD: sqlite3 6331** 6332** ^This interface returns a pointer to the next [prepared statement] after 6333** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6334** then this interface returns a pointer to the first prepared statement 6335** associated with the database connection pDb. ^If no prepared statement 6336** satisfies the conditions of this routine, it returns NULL. 6337** 6338** The [database connection] pointer D in a call to 6339** [sqlite3_next_stmt(D,S)] must refer to an open database 6340** connection and in particular must not be a NULL pointer. 6341*/ 6342sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6343 6344/* 6345** CAPI3REF: Commit And Rollback Notification Callbacks 6346** METHOD: sqlite3 6347** 6348** ^The sqlite3_commit_hook() interface registers a callback 6349** function to be invoked whenever a transaction is [COMMIT | committed]. 6350** ^Any callback set by a previous call to sqlite3_commit_hook() 6351** for the same database connection is overridden. 6352** ^The sqlite3_rollback_hook() interface registers a callback 6353** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6354** ^Any callback set by a previous call to sqlite3_rollback_hook() 6355** for the same database connection is overridden. 6356** ^The pArg argument is passed through to the callback. 6357** ^If the callback on a commit hook function returns non-zero, 6358** then the commit is converted into a rollback. 6359** 6360** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6361** return the P argument from the previous call of the same function 6362** on the same [database connection] D, or NULL for 6363** the first call for each function on D. 6364** 6365** The commit and rollback hook callbacks are not reentrant. 6366** The callback implementation must not do anything that will modify 6367** the database connection that invoked the callback. Any actions 6368** to modify the database connection must be deferred until after the 6369** completion of the [sqlite3_step()] call that triggered the commit 6370** or rollback hook in the first place. 6371** Note that running any other SQL statements, including SELECT statements, 6372** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6373** the database connections for the meaning of "modify" in this paragraph. 6374** 6375** ^Registering a NULL function disables the callback. 6376** 6377** ^When the commit hook callback routine returns zero, the [COMMIT] 6378** operation is allowed to continue normally. ^If the commit hook 6379** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6380** ^The rollback hook is invoked on a rollback that results from a commit 6381** hook returning non-zero, just as it would be with any other rollback. 6382** 6383** ^For the purposes of this API, a transaction is said to have been 6384** rolled back if an explicit "ROLLBACK" statement is executed, or 6385** an error or constraint causes an implicit rollback to occur. 6386** ^The rollback callback is not invoked if a transaction is 6387** automatically rolled back because the database connection is closed. 6388** 6389** See also the [sqlite3_update_hook()] interface. 6390*/ 6391void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6392void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6393 6394/* 6395** CAPI3REF: Data Change Notification Callbacks 6396** METHOD: sqlite3 6397** 6398** ^The sqlite3_update_hook() interface registers a callback function 6399** with the [database connection] identified by the first argument 6400** to be invoked whenever a row is updated, inserted or deleted in 6401** a [rowid table]. 6402** ^Any callback set by a previous call to this function 6403** for the same database connection is overridden. 6404** 6405** ^The second argument is a pointer to the function to invoke when a 6406** row is updated, inserted or deleted in a rowid table. 6407** ^The first argument to the callback is a copy of the third argument 6408** to sqlite3_update_hook(). 6409** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6410** or [SQLITE_UPDATE], depending on the operation that caused the callback 6411** to be invoked. 6412** ^The third and fourth arguments to the callback contain pointers to the 6413** database and table name containing the affected row. 6414** ^The final callback parameter is the [rowid] of the row. 6415** ^In the case of an update, this is the [rowid] after the update takes place. 6416** 6417** ^(The update hook is not invoked when internal system tables are 6418** modified (i.e. sqlite_sequence).)^ 6419** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6420** 6421** ^In the current implementation, the update hook 6422** is not invoked when conflicting rows are deleted because of an 6423** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6424** invoked when rows are deleted using the [truncate optimization]. 6425** The exceptions defined in this paragraph might change in a future 6426** release of SQLite. 6427** 6428** The update hook implementation must not do anything that will modify 6429** the database connection that invoked the update hook. Any actions 6430** to modify the database connection must be deferred until after the 6431** completion of the [sqlite3_step()] call that triggered the update hook. 6432** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6433** database connections for the meaning of "modify" in this paragraph. 6434** 6435** ^The sqlite3_update_hook(D,C,P) function 6436** returns the P argument from the previous call 6437** on the same [database connection] D, or NULL for 6438** the first call on D. 6439** 6440** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6441** and [sqlite3_preupdate_hook()] interfaces. 6442*/ 6443void *sqlite3_update_hook( 6444 sqlite3*, 6445 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6446 void* 6447); 6448 6449/* 6450** CAPI3REF: Enable Or Disable Shared Pager Cache 6451** 6452** ^(This routine enables or disables the sharing of the database cache 6453** and schema data structures between [database connection | connections] 6454** to the same database. Sharing is enabled if the argument is true 6455** and disabled if the argument is false.)^ 6456** 6457** ^Cache sharing is enabled and disabled for an entire process. 6458** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6459** In prior versions of SQLite, 6460** sharing was enabled or disabled for each thread separately. 6461** 6462** ^(The cache sharing mode set by this interface effects all subsequent 6463** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6464** Existing database connections continue to use the sharing mode 6465** that was in effect at the time they were opened.)^ 6466** 6467** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6468** successfully. An [error code] is returned otherwise.)^ 6469** 6470** ^Shared cache is disabled by default. It is recommended that it stay 6471** that way. In other words, do not use this routine. This interface 6472** continues to be provided for historical compatibility, but its use is 6473** discouraged. Any use of shared cache is discouraged. If shared cache 6474** must be used, it is recommended that shared cache only be enabled for 6475** individual database connections using the [sqlite3_open_v2()] interface 6476** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6477** 6478** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6479** and will always return SQLITE_MISUSE. On those systems, 6480** shared cache mode should be enabled per-database connection via 6481** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6482** 6483** This interface is threadsafe on processors where writing a 6484** 32-bit integer is atomic. 6485** 6486** See Also: [SQLite Shared-Cache Mode] 6487*/ 6488int sqlite3_enable_shared_cache(int); 6489 6490/* 6491** CAPI3REF: Attempt To Free Heap Memory 6492** 6493** ^The sqlite3_release_memory() interface attempts to free N bytes 6494** of heap memory by deallocating non-essential memory allocations 6495** held by the database library. Memory used to cache database 6496** pages to improve performance is an example of non-essential memory. 6497** ^sqlite3_release_memory() returns the number of bytes actually freed, 6498** which might be more or less than the amount requested. 6499** ^The sqlite3_release_memory() routine is a no-op returning zero 6500** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6501** 6502** See also: [sqlite3_db_release_memory()] 6503*/ 6504int sqlite3_release_memory(int); 6505 6506/* 6507** CAPI3REF: Free Memory Used By A Database Connection 6508** METHOD: sqlite3 6509** 6510** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6511** memory as possible from database connection D. Unlike the 6512** [sqlite3_release_memory()] interface, this interface is in effect even 6513** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6514** omitted. 6515** 6516** See also: [sqlite3_release_memory()] 6517*/ 6518int sqlite3_db_release_memory(sqlite3*); 6519 6520/* 6521** CAPI3REF: Impose A Limit On Heap Size 6522** 6523** These interfaces impose limits on the amount of heap memory that will be 6524** by all database connections within a single process. 6525** 6526** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 6527** soft limit on the amount of heap memory that may be allocated by SQLite. 6528** ^SQLite strives to keep heap memory utilization below the soft heap 6529** limit by reducing the number of pages held in the page cache 6530** as heap memory usages approaches the limit. 6531** ^The soft heap limit is "soft" because even though SQLite strives to stay 6532** below the limit, it will exceed the limit rather than generate 6533** an [SQLITE_NOMEM] error. In other words, the soft heap limit 6534** is advisory only. 6535** 6536** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 6537** N bytes on the amount of memory that will be allocated. ^The 6538** sqlite3_hard_heap_limit64(N) interface is similar to 6539** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 6540** when the hard heap limit is reached. 6541** 6542** ^The return value from both sqlite3_soft_heap_limit64() and 6543** sqlite3_hard_heap_limit64() is the size of 6544** the heap limit prior to the call, or negative in the case of an 6545** error. ^If the argument N is negative 6546** then no change is made to the heap limit. Hence, the current 6547** size of heap limits can be determined by invoking 6548** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 6549** 6550** ^Setting the heap limits to zero disables the heap limiter mechanism. 6551** 6552** ^The soft heap limit may not be greater than the hard heap limit. 6553** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 6554** is invoked with a value of N that is greater than the hard heap limit, 6555** the the soft heap limit is set to the value of the hard heap limit. 6556** ^The soft heap limit is automatically enabled whenever the hard heap 6557** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 6558** the soft heap limit is outside the range of 1..N, then the soft heap 6559** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 6560** hard heap limit is enabled makes the soft heap limit equal to the 6561** hard heap limit. 6562** 6563** The memory allocation limits can also be adjusted using 6564** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 6565** 6566** ^(The heap limits are not enforced in the current implementation 6567** if one or more of following conditions are true: 6568** 6569** <ul> 6570** <li> The limit value is set to zero. 6571** <li> Memory accounting is disabled using a combination of the 6572** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 6573** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 6574** <li> An alternative page cache implementation is specified using 6575** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 6576** <li> The page cache allocates from its own memory pool supplied 6577** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 6578** from the heap. 6579** </ul>)^ 6580** 6581** The circumstances under which SQLite will enforce the heap limits may 6582** changes in future releases of SQLite. 6583*/ 6584sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 6585sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 6586 6587/* 6588** CAPI3REF: Deprecated Soft Heap Limit Interface 6589** DEPRECATED 6590** 6591** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 6592** interface. This routine is provided for historical compatibility 6593** only. All new applications should use the 6594** [sqlite3_soft_heap_limit64()] interface rather than this one. 6595*/ 6596SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 6597 6598 6599/* 6600** CAPI3REF: Extract Metadata About A Column Of A Table 6601** METHOD: sqlite3 6602** 6603** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 6604** information about column C of table T in database D 6605** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 6606** interface returns SQLITE_OK and fills in the non-NULL pointers in 6607** the final five arguments with appropriate values if the specified 6608** column exists. ^The sqlite3_table_column_metadata() interface returns 6609** SQLITE_ERROR if the specified column does not exist. 6610** ^If the column-name parameter to sqlite3_table_column_metadata() is a 6611** NULL pointer, then this routine simply checks for the existence of the 6612** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 6613** does not. If the table name parameter T in a call to 6614** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 6615** undefined behavior. 6616** 6617** ^The column is identified by the second, third and fourth parameters to 6618** this function. ^(The second parameter is either the name of the database 6619** (i.e. "main", "temp", or an attached database) containing the specified 6620** table or NULL.)^ ^If it is NULL, then all attached databases are searched 6621** for the table using the same algorithm used by the database engine to 6622** resolve unqualified table references. 6623** 6624** ^The third and fourth parameters to this function are the table and column 6625** name of the desired column, respectively. 6626** 6627** ^Metadata is returned by writing to the memory locations passed as the 5th 6628** and subsequent parameters to this function. ^Any of these arguments may be 6629** NULL, in which case the corresponding element of metadata is omitted. 6630** 6631** ^(<blockquote> 6632** <table border="1"> 6633** <tr><th> Parameter <th> Output<br>Type <th> Description 6634** 6635** <tr><td> 5th <td> const char* <td> Data type 6636** <tr><td> 6th <td> const char* <td> Name of default collation sequence 6637** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 6638** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 6639** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 6640** </table> 6641** </blockquote>)^ 6642** 6643** ^The memory pointed to by the character pointers returned for the 6644** declaration type and collation sequence is valid until the next 6645** call to any SQLite API function. 6646** 6647** ^If the specified table is actually a view, an [error code] is returned. 6648** 6649** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 6650** is not a [WITHOUT ROWID] table and an 6651** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 6652** parameters are set for the explicitly declared column. ^(If there is no 6653** [INTEGER PRIMARY KEY] column, then the outputs 6654** for the [rowid] are set as follows: 6655** 6656** <pre> 6657** data type: "INTEGER" 6658** collation sequence: "BINARY" 6659** not null: 0 6660** primary key: 1 6661** auto increment: 0 6662** </pre>)^ 6663** 6664** ^This function causes all database schemas to be read from disk and 6665** parsed, if that has not already been done, and returns an error if 6666** any errors are encountered while loading the schema. 6667*/ 6668int sqlite3_table_column_metadata( 6669 sqlite3 *db, /* Connection handle */ 6670 const char *zDbName, /* Database name or NULL */ 6671 const char *zTableName, /* Table name */ 6672 const char *zColumnName, /* Column name */ 6673 char const **pzDataType, /* OUTPUT: Declared data type */ 6674 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 6675 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 6676 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 6677 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 6678); 6679 6680/* 6681** CAPI3REF: Load An Extension 6682** METHOD: sqlite3 6683** 6684** ^This interface loads an SQLite extension library from the named file. 6685** 6686** ^The sqlite3_load_extension() interface attempts to load an 6687** [SQLite extension] library contained in the file zFile. If 6688** the file cannot be loaded directly, attempts are made to load 6689** with various operating-system specific extensions added. 6690** So for example, if "samplelib" cannot be loaded, then names like 6691** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 6692** be tried also. 6693** 6694** ^The entry point is zProc. 6695** ^(zProc may be 0, in which case SQLite will try to come up with an 6696** entry point name on its own. It first tries "sqlite3_extension_init". 6697** If that does not work, it constructs a name "sqlite3_X_init" where the 6698** X is consists of the lower-case equivalent of all ASCII alphabetic 6699** characters in the filename from the last "/" to the first following 6700** "." and omitting any initial "lib".)^ 6701** ^The sqlite3_load_extension() interface returns 6702** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 6703** ^If an error occurs and pzErrMsg is not 0, then the 6704** [sqlite3_load_extension()] interface shall attempt to 6705** fill *pzErrMsg with error message text stored in memory 6706** obtained from [sqlite3_malloc()]. The calling function 6707** should free this memory by calling [sqlite3_free()]. 6708** 6709** ^Extension loading must be enabled using 6710** [sqlite3_enable_load_extension()] or 6711** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 6712** prior to calling this API, 6713** otherwise an error will be returned. 6714** 6715** <b>Security warning:</b> It is recommended that the 6716** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 6717** interface. The use of the [sqlite3_enable_load_extension()] interface 6718** should be avoided. This will keep the SQL function [load_extension()] 6719** disabled and prevent SQL injections from giving attackers 6720** access to extension loading capabilities. 6721** 6722** See also the [load_extension() SQL function]. 6723*/ 6724int sqlite3_load_extension( 6725 sqlite3 *db, /* Load the extension into this database connection */ 6726 const char *zFile, /* Name of the shared library containing extension */ 6727 const char *zProc, /* Entry point. Derived from zFile if 0 */ 6728 char **pzErrMsg /* Put error message here if not 0 */ 6729); 6730 6731/* 6732** CAPI3REF: Enable Or Disable Extension Loading 6733** METHOD: sqlite3 6734** 6735** ^So as not to open security holes in older applications that are 6736** unprepared to deal with [extension loading], and as a means of disabling 6737** [extension loading] while evaluating user-entered SQL, the following API 6738** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 6739** 6740** ^Extension loading is off by default. 6741** ^Call the sqlite3_enable_load_extension() routine with onoff==1 6742** to turn extension loading on and call it with onoff==0 to turn 6743** it back off again. 6744** 6745** ^This interface enables or disables both the C-API 6746** [sqlite3_load_extension()] and the SQL function [load_extension()]. 6747** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 6748** to enable or disable only the C-API.)^ 6749** 6750** <b>Security warning:</b> It is recommended that extension loading 6751** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 6752** rather than this interface, so the [load_extension()] SQL function 6753** remains disabled. This will prevent SQL injections from giving attackers 6754** access to extension loading capabilities. 6755*/ 6756int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 6757 6758/* 6759** CAPI3REF: Automatically Load Statically Linked Extensions 6760** 6761** ^This interface causes the xEntryPoint() function to be invoked for 6762** each new [database connection] that is created. The idea here is that 6763** xEntryPoint() is the entry point for a statically linked [SQLite extension] 6764** that is to be automatically loaded into all new database connections. 6765** 6766** ^(Even though the function prototype shows that xEntryPoint() takes 6767** no arguments and returns void, SQLite invokes xEntryPoint() with three 6768** arguments and expects an integer result as if the signature of the 6769** entry point where as follows: 6770** 6771** <blockquote><pre> 6772** int xEntryPoint( 6773** sqlite3 *db, 6774** const char **pzErrMsg, 6775** const struct sqlite3_api_routines *pThunk 6776** ); 6777** </pre></blockquote>)^ 6778** 6779** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 6780** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 6781** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 6782** is NULL before calling the xEntryPoint(). ^SQLite will invoke 6783** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 6784** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 6785** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 6786** 6787** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 6788** on the list of automatic extensions is a harmless no-op. ^No entry point 6789** will be called more than once for each database connection that is opened. 6790** 6791** See also: [sqlite3_reset_auto_extension()] 6792** and [sqlite3_cancel_auto_extension()] 6793*/ 6794int sqlite3_auto_extension(void(*xEntryPoint)(void)); 6795 6796/* 6797** CAPI3REF: Cancel Automatic Extension Loading 6798** 6799** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 6800** initialization routine X that was registered using a prior call to 6801** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 6802** routine returns 1 if initialization routine X was successfully 6803** unregistered and it returns 0 if X was not on the list of initialization 6804** routines. 6805*/ 6806int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 6807 6808/* 6809** CAPI3REF: Reset Automatic Extension Loading 6810** 6811** ^This interface disables all automatic extensions previously 6812** registered using [sqlite3_auto_extension()]. 6813*/ 6814void sqlite3_reset_auto_extension(void); 6815 6816/* 6817** The interface to the virtual-table mechanism is currently considered 6818** to be experimental. The interface might change in incompatible ways. 6819** If this is a problem for you, do not use the interface at this time. 6820** 6821** When the virtual-table mechanism stabilizes, we will declare the 6822** interface fixed, support it indefinitely, and remove this comment. 6823*/ 6824 6825/* 6826** Structures used by the virtual table interface 6827*/ 6828typedef struct sqlite3_vtab sqlite3_vtab; 6829typedef struct sqlite3_index_info sqlite3_index_info; 6830typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 6831typedef struct sqlite3_module sqlite3_module; 6832 6833/* 6834** CAPI3REF: Virtual Table Object 6835** KEYWORDS: sqlite3_module {virtual table module} 6836** 6837** This structure, sometimes called a "virtual table module", 6838** defines the implementation of a [virtual table]. 6839** This structure consists mostly of methods for the module. 6840** 6841** ^A virtual table module is created by filling in a persistent 6842** instance of this structure and passing a pointer to that instance 6843** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 6844** ^The registration remains valid until it is replaced by a different 6845** module or until the [database connection] closes. The content 6846** of this structure must not change while it is registered with 6847** any database connection. 6848*/ 6849struct sqlite3_module { 6850 int iVersion; 6851 int (*xCreate)(sqlite3*, void *pAux, 6852 int argc, const char *const*argv, 6853 sqlite3_vtab **ppVTab, char**); 6854 int (*xConnect)(sqlite3*, void *pAux, 6855 int argc, const char *const*argv, 6856 sqlite3_vtab **ppVTab, char**); 6857 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 6858 int (*xDisconnect)(sqlite3_vtab *pVTab); 6859 int (*xDestroy)(sqlite3_vtab *pVTab); 6860 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 6861 int (*xClose)(sqlite3_vtab_cursor*); 6862 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 6863 int argc, sqlite3_value **argv); 6864 int (*xNext)(sqlite3_vtab_cursor*); 6865 int (*xEof)(sqlite3_vtab_cursor*); 6866 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 6867 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 6868 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 6869 int (*xBegin)(sqlite3_vtab *pVTab); 6870 int (*xSync)(sqlite3_vtab *pVTab); 6871 int (*xCommit)(sqlite3_vtab *pVTab); 6872 int (*xRollback)(sqlite3_vtab *pVTab); 6873 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 6874 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 6875 void **ppArg); 6876 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 6877 /* The methods above are in version 1 of the sqlite_module object. Those 6878 ** below are for version 2 and greater. */ 6879 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 6880 int (*xRelease)(sqlite3_vtab *pVTab, int); 6881 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 6882 /* The methods above are in versions 1 and 2 of the sqlite_module object. 6883 ** Those below are for version 3 and greater. */ 6884 int (*xShadowName)(const char*); 6885}; 6886 6887/* 6888** CAPI3REF: Virtual Table Indexing Information 6889** KEYWORDS: sqlite3_index_info 6890** 6891** The sqlite3_index_info structure and its substructures is used as part 6892** of the [virtual table] interface to 6893** pass information into and receive the reply from the [xBestIndex] 6894** method of a [virtual table module]. The fields under **Inputs** are the 6895** inputs to xBestIndex and are read-only. xBestIndex inserts its 6896** results into the **Outputs** fields. 6897** 6898** ^(The aConstraint[] array records WHERE clause constraints of the form: 6899** 6900** <blockquote>column OP expr</blockquote> 6901** 6902** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 6903** stored in aConstraint[].op using one of the 6904** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 6905** ^(The index of the column is stored in 6906** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 6907** expr on the right-hand side can be evaluated (and thus the constraint 6908** is usable) and false if it cannot.)^ 6909** 6910** ^The optimizer automatically inverts terms of the form "expr OP column" 6911** and makes other simplifications to the WHERE clause in an attempt to 6912** get as many WHERE clause terms into the form shown above as possible. 6913** ^The aConstraint[] array only reports WHERE clause terms that are 6914** relevant to the particular virtual table being queried. 6915** 6916** ^Information about the ORDER BY clause is stored in aOrderBy[]. 6917** ^Each term of aOrderBy records a column of the ORDER BY clause. 6918** 6919** The colUsed field indicates which columns of the virtual table may be 6920** required by the current scan. Virtual table columns are numbered from 6921** zero in the order in which they appear within the CREATE TABLE statement 6922** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 6923** the corresponding bit is set within the colUsed mask if the column may be 6924** required by SQLite. If the table has at least 64 columns and any column 6925** to the right of the first 63 is required, then bit 63 of colUsed is also 6926** set. In other words, column iCol may be required if the expression 6927** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 6928** non-zero. 6929** 6930** The [xBestIndex] method must fill aConstraintUsage[] with information 6931** about what parameters to pass to xFilter. ^If argvIndex>0 then 6932** the right-hand side of the corresponding aConstraint[] is evaluated 6933** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 6934** is true, then the constraint is assumed to be fully handled by the 6935** virtual table and might not be checked again by the byte code.)^ ^(The 6936** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 6937** is left in its default setting of false, the constraint will always be 6938** checked separately in byte code. If the omit flag is change to true, then 6939** the constraint may or may not be checked in byte code. In other words, 6940** when the omit flag is true there is no guarantee that the constraint will 6941** not be checked again using byte code.)^ 6942** 6943** ^The idxNum and idxPtr values are recorded and passed into the 6944** [xFilter] method. 6945** ^[sqlite3_free()] is used to free idxPtr if and only if 6946** needToFreeIdxPtr is true. 6947** 6948** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 6949** the correct order to satisfy the ORDER BY clause so that no separate 6950** sorting step is required. 6951** 6952** ^The estimatedCost value is an estimate of the cost of a particular 6953** strategy. A cost of N indicates that the cost of the strategy is similar 6954** to a linear scan of an SQLite table with N rows. A cost of log(N) 6955** indicates that the expense of the operation is similar to that of a 6956** binary search on a unique indexed field of an SQLite table with N rows. 6957** 6958** ^The estimatedRows value is an estimate of the number of rows that 6959** will be returned by the strategy. 6960** 6961** The xBestIndex method may optionally populate the idxFlags field with a 6962** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 6963** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 6964** assumes that the strategy may visit at most one row. 6965** 6966** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 6967** SQLite also assumes that if a call to the xUpdate() method is made as 6968** part of the same statement to delete or update a virtual table row and the 6969** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 6970** any database changes. In other words, if the xUpdate() returns 6971** SQLITE_CONSTRAINT, the database contents must be exactly as they were 6972** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 6973** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 6974** the xUpdate method are automatically rolled back by SQLite. 6975** 6976** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 6977** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 6978** If a virtual table extension is 6979** used with an SQLite version earlier than 3.8.2, the results of attempting 6980** to read or write the estimatedRows field are undefined (but are likely 6981** to include crashing the application). The estimatedRows field should 6982** therefore only be used if [sqlite3_libversion_number()] returns a 6983** value greater than or equal to 3008002. Similarly, the idxFlags field 6984** was added for [version 3.9.0] ([dateof:3.9.0]). 6985** It may therefore only be used if 6986** sqlite3_libversion_number() returns a value greater than or equal to 6987** 3009000. 6988*/ 6989struct sqlite3_index_info { 6990 /* Inputs */ 6991 int nConstraint; /* Number of entries in aConstraint */ 6992 struct sqlite3_index_constraint { 6993 int iColumn; /* Column constrained. -1 for ROWID */ 6994 unsigned char op; /* Constraint operator */ 6995 unsigned char usable; /* True if this constraint is usable */ 6996 int iTermOffset; /* Used internally - xBestIndex should ignore */ 6997 } *aConstraint; /* Table of WHERE clause constraints */ 6998 int nOrderBy; /* Number of terms in the ORDER BY clause */ 6999 struct sqlite3_index_orderby { 7000 int iColumn; /* Column number */ 7001 unsigned char desc; /* True for DESC. False for ASC. */ 7002 } *aOrderBy; /* The ORDER BY clause */ 7003 /* Outputs */ 7004 struct sqlite3_index_constraint_usage { 7005 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 7006 unsigned char omit; /* Do not code a test for this constraint */ 7007 } *aConstraintUsage; 7008 int idxNum; /* Number used to identify the index */ 7009 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 7010 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 7011 int orderByConsumed; /* True if output is already ordered */ 7012 double estimatedCost; /* Estimated cost of using this index */ 7013 /* Fields below are only available in SQLite 3.8.2 and later */ 7014 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 7015 /* Fields below are only available in SQLite 3.9.0 and later */ 7016 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 7017 /* Fields below are only available in SQLite 3.10.0 and later */ 7018 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 7019}; 7020 7021/* 7022** CAPI3REF: Virtual Table Scan Flags 7023** 7024** Virtual table implementations are allowed to set the 7025** [sqlite3_index_info].idxFlags field to some combination of 7026** these bits. 7027*/ 7028#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 7029 7030/* 7031** CAPI3REF: Virtual Table Constraint Operator Codes 7032** 7033** These macros define the allowed values for the 7034** [sqlite3_index_info].aConstraint[].op field. Each value represents 7035** an operator that is part of a constraint term in the wHERE clause of 7036** a query that uses a [virtual table]. 7037*/ 7038#define SQLITE_INDEX_CONSTRAINT_EQ 2 7039#define SQLITE_INDEX_CONSTRAINT_GT 4 7040#define SQLITE_INDEX_CONSTRAINT_LE 8 7041#define SQLITE_INDEX_CONSTRAINT_LT 16 7042#define SQLITE_INDEX_CONSTRAINT_GE 32 7043#define SQLITE_INDEX_CONSTRAINT_MATCH 64 7044#define SQLITE_INDEX_CONSTRAINT_LIKE 65 7045#define SQLITE_INDEX_CONSTRAINT_GLOB 66 7046#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 7047#define SQLITE_INDEX_CONSTRAINT_NE 68 7048#define SQLITE_INDEX_CONSTRAINT_ISNOT 69 7049#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 7050#define SQLITE_INDEX_CONSTRAINT_ISNULL 71 7051#define SQLITE_INDEX_CONSTRAINT_IS 72 7052#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 7053 7054/* 7055** CAPI3REF: Register A Virtual Table Implementation 7056** METHOD: sqlite3 7057** 7058** ^These routines are used to register a new [virtual table module] name. 7059** ^Module names must be registered before 7060** creating a new [virtual table] using the module and before using a 7061** preexisting [virtual table] for the module. 7062** 7063** ^The module name is registered on the [database connection] specified 7064** by the first parameter. ^The name of the module is given by the 7065** second parameter. ^The third parameter is a pointer to 7066** the implementation of the [virtual table module]. ^The fourth 7067** parameter is an arbitrary client data pointer that is passed through 7068** into the [xCreate] and [xConnect] methods of the virtual table module 7069** when a new virtual table is be being created or reinitialized. 7070** 7071** ^The sqlite3_create_module_v2() interface has a fifth parameter which 7072** is a pointer to a destructor for the pClientData. ^SQLite will 7073** invoke the destructor function (if it is not NULL) when SQLite 7074** no longer needs the pClientData pointer. ^The destructor will also 7075** be invoked if the call to sqlite3_create_module_v2() fails. 7076** ^The sqlite3_create_module() 7077** interface is equivalent to sqlite3_create_module_v2() with a NULL 7078** destructor. 7079** 7080** ^If the third parameter (the pointer to the sqlite3_module object) is 7081** NULL then no new module is create and any existing modules with the 7082** same name are dropped. 7083** 7084** See also: [sqlite3_drop_modules()] 7085*/ 7086int sqlite3_create_module( 7087 sqlite3 *db, /* SQLite connection to register module with */ 7088 const char *zName, /* Name of the module */ 7089 const sqlite3_module *p, /* Methods for the module */ 7090 void *pClientData /* Client data for xCreate/xConnect */ 7091); 7092int sqlite3_create_module_v2( 7093 sqlite3 *db, /* SQLite connection to register module with */ 7094 const char *zName, /* Name of the module */ 7095 const sqlite3_module *p, /* Methods for the module */ 7096 void *pClientData, /* Client data for xCreate/xConnect */ 7097 void(*xDestroy)(void*) /* Module destructor function */ 7098); 7099 7100/* 7101** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7102** METHOD: sqlite3 7103** 7104** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7105** table modules from database connection D except those named on list L. 7106** The L parameter must be either NULL or a pointer to an array of pointers 7107** to strings where the array is terminated by a single NULL pointer. 7108** ^If the L parameter is NULL, then all virtual table modules are removed. 7109** 7110** See also: [sqlite3_create_module()] 7111*/ 7112int sqlite3_drop_modules( 7113 sqlite3 *db, /* Remove modules from this connection */ 7114 const char **azKeep /* Except, do not remove the ones named here */ 7115); 7116 7117/* 7118** CAPI3REF: Virtual Table Instance Object 7119** KEYWORDS: sqlite3_vtab 7120** 7121** Every [virtual table module] implementation uses a subclass 7122** of this object to describe a particular instance 7123** of the [virtual table]. Each subclass will 7124** be tailored to the specific needs of the module implementation. 7125** The purpose of this superclass is to define certain fields that are 7126** common to all module implementations. 7127** 7128** ^Virtual tables methods can set an error message by assigning a 7129** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 7130** take care that any prior string is freed by a call to [sqlite3_free()] 7131** prior to assigning a new string to zErrMsg. ^After the error message 7132** is delivered up to the client application, the string will be automatically 7133** freed by sqlite3_free() and the zErrMsg field will be zeroed. 7134*/ 7135struct sqlite3_vtab { 7136 const sqlite3_module *pModule; /* The module for this virtual table */ 7137 int nRef; /* Number of open cursors */ 7138 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 7139 /* Virtual table implementations will typically add additional fields */ 7140}; 7141 7142/* 7143** CAPI3REF: Virtual Table Cursor Object 7144** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 7145** 7146** Every [virtual table module] implementation uses a subclass of the 7147** following structure to describe cursors that point into the 7148** [virtual table] and are used 7149** to loop through the virtual table. Cursors are created using the 7150** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 7151** by the [sqlite3_module.xClose | xClose] method. Cursors are used 7152** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 7153** of the module. Each module implementation will define 7154** the content of a cursor structure to suit its own needs. 7155** 7156** This superclass exists in order to define fields of the cursor that 7157** are common to all implementations. 7158*/ 7159struct sqlite3_vtab_cursor { 7160 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 7161 /* Virtual table implementations will typically add additional fields */ 7162}; 7163 7164/* 7165** CAPI3REF: Declare The Schema Of A Virtual Table 7166** 7167** ^The [xCreate] and [xConnect] methods of a 7168** [virtual table module] call this interface 7169** to declare the format (the names and datatypes of the columns) of 7170** the virtual tables they implement. 7171*/ 7172int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 7173 7174/* 7175** CAPI3REF: Overload A Function For A Virtual Table 7176** METHOD: sqlite3 7177** 7178** ^(Virtual tables can provide alternative implementations of functions 7179** using the [xFindFunction] method of the [virtual table module]. 7180** But global versions of those functions 7181** must exist in order to be overloaded.)^ 7182** 7183** ^(This API makes sure a global version of a function with a particular 7184** name and number of parameters exists. If no such function exists 7185** before this API is called, a new function is created.)^ ^The implementation 7186** of the new function always causes an exception to be thrown. So 7187** the new function is not good for anything by itself. Its only 7188** purpose is to be a placeholder function that can be overloaded 7189** by a [virtual table]. 7190*/ 7191int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 7192 7193/* 7194** The interface to the virtual-table mechanism defined above (back up 7195** to a comment remarkably similar to this one) is currently considered 7196** to be experimental. The interface might change in incompatible ways. 7197** If this is a problem for you, do not use the interface at this time. 7198** 7199** When the virtual-table mechanism stabilizes, we will declare the 7200** interface fixed, support it indefinitely, and remove this comment. 7201*/ 7202 7203/* 7204** CAPI3REF: A Handle To An Open BLOB 7205** KEYWORDS: {BLOB handle} {BLOB handles} 7206** 7207** An instance of this object represents an open BLOB on which 7208** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 7209** ^Objects of this type are created by [sqlite3_blob_open()] 7210** and destroyed by [sqlite3_blob_close()]. 7211** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 7212** can be used to read or write small subsections of the BLOB. 7213** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 7214*/ 7215typedef struct sqlite3_blob sqlite3_blob; 7216 7217/* 7218** CAPI3REF: Open A BLOB For Incremental I/O 7219** METHOD: sqlite3 7220** CONSTRUCTOR: sqlite3_blob 7221** 7222** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 7223** in row iRow, column zColumn, table zTable in database zDb; 7224** in other words, the same BLOB that would be selected by: 7225** 7226** <pre> 7227** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7228** </pre>)^ 7229** 7230** ^(Parameter zDb is not the filename that contains the database, but 7231** rather the symbolic name of the database. For attached databases, this is 7232** the name that appears after the AS keyword in the [ATTACH] statement. 7233** For the main database file, the database name is "main". For TEMP 7234** tables, the database name is "temp".)^ 7235** 7236** ^If the flags parameter is non-zero, then the BLOB is opened for read 7237** and write access. ^If the flags parameter is zero, the BLOB is opened for 7238** read-only access. 7239** 7240** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7241** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7242** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7243** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7244** on *ppBlob after this function it returns. 7245** 7246** This function fails with SQLITE_ERROR if any of the following are true: 7247** <ul> 7248** <li> ^(Database zDb does not exist)^, 7249** <li> ^(Table zTable does not exist within database zDb)^, 7250** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7251** <li> ^(Column zColumn does not exist)^, 7252** <li> ^(Row iRow is not present in the table)^, 7253** <li> ^(The specified column of row iRow contains a value that is not 7254** a TEXT or BLOB value)^, 7255** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7256** constraint and the blob is being opened for read/write access)^, 7257** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7258** column zColumn is part of a [child key] definition and the blob is 7259** being opened for read/write access)^. 7260** </ul> 7261** 7262** ^Unless it returns SQLITE_MISUSE, this function sets the 7263** [database connection] error code and message accessible via 7264** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7265** 7266** A BLOB referenced by sqlite3_blob_open() may be read using the 7267** [sqlite3_blob_read()] interface and modified by using 7268** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7269** different row of the same table using the [sqlite3_blob_reopen()] 7270** interface. However, the column, table, or database of a [BLOB handle] 7271** cannot be changed after the [BLOB handle] is opened. 7272** 7273** ^(If the row that a BLOB handle points to is modified by an 7274** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7275** then the BLOB handle is marked as "expired". 7276** This is true if any column of the row is changed, even a column 7277** other than the one the BLOB handle is open on.)^ 7278** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7279** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7280** ^(Changes written into a BLOB prior to the BLOB expiring are not 7281** rolled back by the expiration of the BLOB. Such changes will eventually 7282** commit if the transaction continues to completion.)^ 7283** 7284** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7285** the opened blob. ^The size of a blob may not be changed by this 7286** interface. Use the [UPDATE] SQL command to change the size of a 7287** blob. 7288** 7289** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7290** and the built-in [zeroblob] SQL function may be used to create a 7291** zero-filled blob to read or write using the incremental-blob interface. 7292** 7293** To avoid a resource leak, every open [BLOB handle] should eventually 7294** be released by a call to [sqlite3_blob_close()]. 7295** 7296** See also: [sqlite3_blob_close()], 7297** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7298** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7299*/ 7300int sqlite3_blob_open( 7301 sqlite3*, 7302 const char *zDb, 7303 const char *zTable, 7304 const char *zColumn, 7305 sqlite3_int64 iRow, 7306 int flags, 7307 sqlite3_blob **ppBlob 7308); 7309 7310/* 7311** CAPI3REF: Move a BLOB Handle to a New Row 7312** METHOD: sqlite3_blob 7313** 7314** ^This function is used to move an existing [BLOB handle] so that it points 7315** to a different row of the same database table. ^The new row is identified 7316** by the rowid value passed as the second argument. Only the row can be 7317** changed. ^The database, table and column on which the blob handle is open 7318** remain the same. Moving an existing [BLOB handle] to a new row is 7319** faster than closing the existing handle and opening a new one. 7320** 7321** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7322** it must exist and there must be either a blob or text value stored in 7323** the nominated column.)^ ^If the new row is not present in the table, or if 7324** it does not contain a blob or text value, or if another error occurs, an 7325** SQLite error code is returned and the blob handle is considered aborted. 7326** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7327** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7328** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7329** always returns zero. 7330** 7331** ^This function sets the database handle error code and message. 7332*/ 7333int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7334 7335/* 7336** CAPI3REF: Close A BLOB Handle 7337** DESTRUCTOR: sqlite3_blob 7338** 7339** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7340** unconditionally. Even if this routine returns an error code, the 7341** handle is still closed.)^ 7342** 7343** ^If the blob handle being closed was opened for read-write access, and if 7344** the database is in auto-commit mode and there are no other open read-write 7345** blob handles or active write statements, the current transaction is 7346** committed. ^If an error occurs while committing the transaction, an error 7347** code is returned and the transaction rolled back. 7348** 7349** Calling this function with an argument that is not a NULL pointer or an 7350** open blob handle results in undefined behaviour. ^Calling this routine 7351** with a null pointer (such as would be returned by a failed call to 7352** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7353** is passed a valid open blob handle, the values returned by the 7354** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7355*/ 7356int sqlite3_blob_close(sqlite3_blob *); 7357 7358/* 7359** CAPI3REF: Return The Size Of An Open BLOB 7360** METHOD: sqlite3_blob 7361** 7362** ^Returns the size in bytes of the BLOB accessible via the 7363** successfully opened [BLOB handle] in its only argument. ^The 7364** incremental blob I/O routines can only read or overwriting existing 7365** blob content; they cannot change the size of a blob. 7366** 7367** This routine only works on a [BLOB handle] which has been created 7368** by a prior successful call to [sqlite3_blob_open()] and which has not 7369** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7370** to this routine results in undefined and probably undesirable behavior. 7371*/ 7372int sqlite3_blob_bytes(sqlite3_blob *); 7373 7374/* 7375** CAPI3REF: Read Data From A BLOB Incrementally 7376** METHOD: sqlite3_blob 7377** 7378** ^(This function is used to read data from an open [BLOB handle] into a 7379** caller-supplied buffer. N bytes of data are copied into buffer Z 7380** from the open BLOB, starting at offset iOffset.)^ 7381** 7382** ^If offset iOffset is less than N bytes from the end of the BLOB, 7383** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7384** less than zero, [SQLITE_ERROR] is returned and no data is read. 7385** ^The size of the blob (and hence the maximum value of N+iOffset) 7386** can be determined using the [sqlite3_blob_bytes()] interface. 7387** 7388** ^An attempt to read from an expired [BLOB handle] fails with an 7389** error code of [SQLITE_ABORT]. 7390** 7391** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7392** Otherwise, an [error code] or an [extended error code] is returned.)^ 7393** 7394** This routine only works on a [BLOB handle] which has been created 7395** by a prior successful call to [sqlite3_blob_open()] and which has not 7396** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7397** to this routine results in undefined and probably undesirable behavior. 7398** 7399** See also: [sqlite3_blob_write()]. 7400*/ 7401int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7402 7403/* 7404** CAPI3REF: Write Data Into A BLOB Incrementally 7405** METHOD: sqlite3_blob 7406** 7407** ^(This function is used to write data into an open [BLOB handle] from a 7408** caller-supplied buffer. N bytes of data are copied from the buffer Z 7409** into the open BLOB, starting at offset iOffset.)^ 7410** 7411** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7412** Otherwise, an [error code] or an [extended error code] is returned.)^ 7413** ^Unless SQLITE_MISUSE is returned, this function sets the 7414** [database connection] error code and message accessible via 7415** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7416** 7417** ^If the [BLOB handle] passed as the first argument was not opened for 7418** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7419** this function returns [SQLITE_READONLY]. 7420** 7421** This function may only modify the contents of the BLOB; it is 7422** not possible to increase the size of a BLOB using this API. 7423** ^If offset iOffset is less than N bytes from the end of the BLOB, 7424** [SQLITE_ERROR] is returned and no data is written. The size of the 7425** BLOB (and hence the maximum value of N+iOffset) can be determined 7426** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7427** than zero [SQLITE_ERROR] is returned and no data is written. 7428** 7429** ^An attempt to write to an expired [BLOB handle] fails with an 7430** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7431** before the [BLOB handle] expired are not rolled back by the 7432** expiration of the handle, though of course those changes might 7433** have been overwritten by the statement that expired the BLOB handle 7434** or by other independent statements. 7435** 7436** This routine only works on a [BLOB handle] which has been created 7437** by a prior successful call to [sqlite3_blob_open()] and which has not 7438** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7439** to this routine results in undefined and probably undesirable behavior. 7440** 7441** See also: [sqlite3_blob_read()]. 7442*/ 7443int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7444 7445/* 7446** CAPI3REF: Virtual File System Objects 7447** 7448** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7449** that SQLite uses to interact 7450** with the underlying operating system. Most SQLite builds come with a 7451** single default VFS that is appropriate for the host computer. 7452** New VFSes can be registered and existing VFSes can be unregistered. 7453** The following interfaces are provided. 7454** 7455** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7456** ^Names are case sensitive. 7457** ^Names are zero-terminated UTF-8 strings. 7458** ^If there is no match, a NULL pointer is returned. 7459** ^If zVfsName is NULL then the default VFS is returned. 7460** 7461** ^New VFSes are registered with sqlite3_vfs_register(). 7462** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7463** ^The same VFS can be registered multiple times without injury. 7464** ^To make an existing VFS into the default VFS, register it again 7465** with the makeDflt flag set. If two different VFSes with the 7466** same name are registered, the behavior is undefined. If a 7467** VFS is registered with a name that is NULL or an empty string, 7468** then the behavior is undefined. 7469** 7470** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7471** ^(If the default VFS is unregistered, another VFS is chosen as 7472** the default. The choice for the new VFS is arbitrary.)^ 7473*/ 7474sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7475int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7476int sqlite3_vfs_unregister(sqlite3_vfs*); 7477 7478/* 7479** CAPI3REF: Mutexes 7480** 7481** The SQLite core uses these routines for thread 7482** synchronization. Though they are intended for internal 7483** use by SQLite, code that links against SQLite is 7484** permitted to use any of these routines. 7485** 7486** The SQLite source code contains multiple implementations 7487** of these mutex routines. An appropriate implementation 7488** is selected automatically at compile-time. The following 7489** implementations are available in the SQLite core: 7490** 7491** <ul> 7492** <li> SQLITE_MUTEX_PTHREADS 7493** <li> SQLITE_MUTEX_W32 7494** <li> SQLITE_MUTEX_NOOP 7495** </ul> 7496** 7497** The SQLITE_MUTEX_NOOP implementation is a set of routines 7498** that does no real locking and is appropriate for use in 7499** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7500** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7501** and Windows. 7502** 7503** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7504** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7505** implementation is included with the library. In this case the 7506** application must supply a custom mutex implementation using the 7507** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7508** before calling sqlite3_initialize() or any other public sqlite3_ 7509** function that calls sqlite3_initialize(). 7510** 7511** ^The sqlite3_mutex_alloc() routine allocates a new 7512** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 7513** routine returns NULL if it is unable to allocate the requested 7514** mutex. The argument to sqlite3_mutex_alloc() must one of these 7515** integer constants: 7516** 7517** <ul> 7518** <li> SQLITE_MUTEX_FAST 7519** <li> SQLITE_MUTEX_RECURSIVE 7520** <li> SQLITE_MUTEX_STATIC_MAIN 7521** <li> SQLITE_MUTEX_STATIC_MEM 7522** <li> SQLITE_MUTEX_STATIC_OPEN 7523** <li> SQLITE_MUTEX_STATIC_PRNG 7524** <li> SQLITE_MUTEX_STATIC_LRU 7525** <li> SQLITE_MUTEX_STATIC_PMEM 7526** <li> SQLITE_MUTEX_STATIC_APP1 7527** <li> SQLITE_MUTEX_STATIC_APP2 7528** <li> SQLITE_MUTEX_STATIC_APP3 7529** <li> SQLITE_MUTEX_STATIC_VFS1 7530** <li> SQLITE_MUTEX_STATIC_VFS2 7531** <li> SQLITE_MUTEX_STATIC_VFS3 7532** </ul> 7533** 7534** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 7535** cause sqlite3_mutex_alloc() to create 7536** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 7537** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 7538** The mutex implementation does not need to make a distinction 7539** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 7540** not want to. SQLite will only request a recursive mutex in 7541** cases where it really needs one. If a faster non-recursive mutex 7542** implementation is available on the host platform, the mutex subsystem 7543** might return such a mutex in response to SQLITE_MUTEX_FAST. 7544** 7545** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 7546** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 7547** a pointer to a static preexisting mutex. ^Nine static mutexes are 7548** used by the current version of SQLite. Future versions of SQLite 7549** may add additional static mutexes. Static mutexes are for internal 7550** use by SQLite only. Applications that use SQLite mutexes should 7551** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 7552** SQLITE_MUTEX_RECURSIVE. 7553** 7554** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 7555** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 7556** returns a different mutex on every call. ^For the static 7557** mutex types, the same mutex is returned on every call that has 7558** the same type number. 7559** 7560** ^The sqlite3_mutex_free() routine deallocates a previously 7561** allocated dynamic mutex. Attempting to deallocate a static 7562** mutex results in undefined behavior. 7563** 7564** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 7565** to enter a mutex. ^If another thread is already within the mutex, 7566** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 7567** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 7568** upon successful entry. ^(Mutexes created using 7569** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 7570** In such cases, the 7571** mutex must be exited an equal number of times before another thread 7572** can enter.)^ If the same thread tries to enter any mutex other 7573** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 7574** 7575** ^(Some systems (for example, Windows 95) do not support the operation 7576** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 7577** will always return SQLITE_BUSY. The SQLite core only ever uses 7578** sqlite3_mutex_try() as an optimization so this is acceptable 7579** behavior.)^ 7580** 7581** ^The sqlite3_mutex_leave() routine exits a mutex that was 7582** previously entered by the same thread. The behavior 7583** is undefined if the mutex is not currently entered by the 7584** calling thread or is not currently allocated. 7585** 7586** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 7587** sqlite3_mutex_leave() is a NULL pointer, then all three routines 7588** behave as no-ops. 7589** 7590** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 7591*/ 7592sqlite3_mutex *sqlite3_mutex_alloc(int); 7593void sqlite3_mutex_free(sqlite3_mutex*); 7594void sqlite3_mutex_enter(sqlite3_mutex*); 7595int sqlite3_mutex_try(sqlite3_mutex*); 7596void sqlite3_mutex_leave(sqlite3_mutex*); 7597 7598/* 7599** CAPI3REF: Mutex Methods Object 7600** 7601** An instance of this structure defines the low-level routines 7602** used to allocate and use mutexes. 7603** 7604** Usually, the default mutex implementations provided by SQLite are 7605** sufficient, however the application has the option of substituting a custom 7606** implementation for specialized deployments or systems for which SQLite 7607** does not provide a suitable implementation. In this case, the application 7608** creates and populates an instance of this structure to pass 7609** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 7610** Additionally, an instance of this structure can be used as an 7611** output variable when querying the system for the current mutex 7612** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 7613** 7614** ^The xMutexInit method defined by this structure is invoked as 7615** part of system initialization by the sqlite3_initialize() function. 7616** ^The xMutexInit routine is called by SQLite exactly once for each 7617** effective call to [sqlite3_initialize()]. 7618** 7619** ^The xMutexEnd method defined by this structure is invoked as 7620** part of system shutdown by the sqlite3_shutdown() function. The 7621** implementation of this method is expected to release all outstanding 7622** resources obtained by the mutex methods implementation, especially 7623** those obtained by the xMutexInit method. ^The xMutexEnd() 7624** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 7625** 7626** ^(The remaining seven methods defined by this structure (xMutexAlloc, 7627** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 7628** xMutexNotheld) implement the following interfaces (respectively): 7629** 7630** <ul> 7631** <li> [sqlite3_mutex_alloc()] </li> 7632** <li> [sqlite3_mutex_free()] </li> 7633** <li> [sqlite3_mutex_enter()] </li> 7634** <li> [sqlite3_mutex_try()] </li> 7635** <li> [sqlite3_mutex_leave()] </li> 7636** <li> [sqlite3_mutex_held()] </li> 7637** <li> [sqlite3_mutex_notheld()] </li> 7638** </ul>)^ 7639** 7640** The only difference is that the public sqlite3_XXX functions enumerated 7641** above silently ignore any invocations that pass a NULL pointer instead 7642** of a valid mutex handle. The implementations of the methods defined 7643** by this structure are not required to handle this case. The results 7644** of passing a NULL pointer instead of a valid mutex handle are undefined 7645** (i.e. it is acceptable to provide an implementation that segfaults if 7646** it is passed a NULL pointer). 7647** 7648** The xMutexInit() method must be threadsafe. It must be harmless to 7649** invoke xMutexInit() multiple times within the same process and without 7650** intervening calls to xMutexEnd(). Second and subsequent calls to 7651** xMutexInit() must be no-ops. 7652** 7653** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 7654** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 7655** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 7656** memory allocation for a fast or recursive mutex. 7657** 7658** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 7659** called, but only if the prior call to xMutexInit returned SQLITE_OK. 7660** If xMutexInit fails in any way, it is expected to clean up after itself 7661** prior to returning. 7662*/ 7663typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 7664struct sqlite3_mutex_methods { 7665 int (*xMutexInit)(void); 7666 int (*xMutexEnd)(void); 7667 sqlite3_mutex *(*xMutexAlloc)(int); 7668 void (*xMutexFree)(sqlite3_mutex *); 7669 void (*xMutexEnter)(sqlite3_mutex *); 7670 int (*xMutexTry)(sqlite3_mutex *); 7671 void (*xMutexLeave)(sqlite3_mutex *); 7672 int (*xMutexHeld)(sqlite3_mutex *); 7673 int (*xMutexNotheld)(sqlite3_mutex *); 7674}; 7675 7676/* 7677** CAPI3REF: Mutex Verification Routines 7678** 7679** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 7680** are intended for use inside assert() statements. The SQLite core 7681** never uses these routines except inside an assert() and applications 7682** are advised to follow the lead of the core. The SQLite core only 7683** provides implementations for these routines when it is compiled 7684** with the SQLITE_DEBUG flag. External mutex implementations 7685** are only required to provide these routines if SQLITE_DEBUG is 7686** defined and if NDEBUG is not defined. 7687** 7688** These routines should return true if the mutex in their argument 7689** is held or not held, respectively, by the calling thread. 7690** 7691** The implementation is not required to provide versions of these 7692** routines that actually work. If the implementation does not provide working 7693** versions of these routines, it should at least provide stubs that always 7694** return true so that one does not get spurious assertion failures. 7695** 7696** If the argument to sqlite3_mutex_held() is a NULL pointer then 7697** the routine should return 1. This seems counter-intuitive since 7698** clearly the mutex cannot be held if it does not exist. But 7699** the reason the mutex does not exist is because the build is not 7700** using mutexes. And we do not want the assert() containing the 7701** call to sqlite3_mutex_held() to fail, so a non-zero return is 7702** the appropriate thing to do. The sqlite3_mutex_notheld() 7703** interface should also return 1 when given a NULL pointer. 7704*/ 7705#ifndef NDEBUG 7706int sqlite3_mutex_held(sqlite3_mutex*); 7707int sqlite3_mutex_notheld(sqlite3_mutex*); 7708#endif 7709 7710/* 7711** CAPI3REF: Mutex Types 7712** 7713** The [sqlite3_mutex_alloc()] interface takes a single argument 7714** which is one of these integer constants. 7715** 7716** The set of static mutexes may change from one SQLite release to the 7717** next. Applications that override the built-in mutex logic must be 7718** prepared to accommodate additional static mutexes. 7719*/ 7720#define SQLITE_MUTEX_FAST 0 7721#define SQLITE_MUTEX_RECURSIVE 1 7722#define SQLITE_MUTEX_STATIC_MAIN 2 7723#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 7724#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 7725#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 7726#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 7727#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 7728#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 7729#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 7730#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 7731#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 7732#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 7733#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 7734#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 7735#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 7736 7737/* Legacy compatibility: */ 7738#define SQLITE_MUTEX_STATIC_MASTER 2 7739 7740 7741/* 7742** CAPI3REF: Retrieve the mutex for a database connection 7743** METHOD: sqlite3 7744** 7745** ^This interface returns a pointer the [sqlite3_mutex] object that 7746** serializes access to the [database connection] given in the argument 7747** when the [threading mode] is Serialized. 7748** ^If the [threading mode] is Single-thread or Multi-thread then this 7749** routine returns a NULL pointer. 7750*/ 7751sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 7752 7753/* 7754** CAPI3REF: Low-Level Control Of Database Files 7755** METHOD: sqlite3 7756** KEYWORDS: {file control} 7757** 7758** ^The [sqlite3_file_control()] interface makes a direct call to the 7759** xFileControl method for the [sqlite3_io_methods] object associated 7760** with a particular database identified by the second argument. ^The 7761** name of the database is "main" for the main database or "temp" for the 7762** TEMP database, or the name that appears after the AS keyword for 7763** databases that are added using the [ATTACH] SQL command. 7764** ^A NULL pointer can be used in place of "main" to refer to the 7765** main database file. 7766** ^The third and fourth parameters to this routine 7767** are passed directly through to the second and third parameters of 7768** the xFileControl method. ^The return value of the xFileControl 7769** method becomes the return value of this routine. 7770** 7771** A few opcodes for [sqlite3_file_control()] are handled directly 7772** by the SQLite core and never invoke the 7773** sqlite3_io_methods.xFileControl method. 7774** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 7775** a pointer to the underlying [sqlite3_file] object to be written into 7776** the space pointed to by the 4th parameter. The 7777** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 7778** the [sqlite3_file] object associated with the journal file instead of 7779** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 7780** a pointer to the underlying [sqlite3_vfs] object for the file. 7781** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 7782** from the pager. 7783** 7784** ^If the second parameter (zDbName) does not match the name of any 7785** open database file, then SQLITE_ERROR is returned. ^This error 7786** code is not remembered and will not be recalled by [sqlite3_errcode()] 7787** or [sqlite3_errmsg()]. The underlying xFileControl method might 7788** also return SQLITE_ERROR. There is no way to distinguish between 7789** an incorrect zDbName and an SQLITE_ERROR return from the underlying 7790** xFileControl method. 7791** 7792** See also: [file control opcodes] 7793*/ 7794int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 7795 7796/* 7797** CAPI3REF: Testing Interface 7798** 7799** ^The sqlite3_test_control() interface is used to read out internal 7800** state of SQLite and to inject faults into SQLite for testing 7801** purposes. ^The first parameter is an operation code that determines 7802** the number, meaning, and operation of all subsequent parameters. 7803** 7804** This interface is not for use by applications. It exists solely 7805** for verifying the correct operation of the SQLite library. Depending 7806** on how the SQLite library is compiled, this interface might not exist. 7807** 7808** The details of the operation codes, their meanings, the parameters 7809** they take, and what they do are all subject to change without notice. 7810** Unlike most of the SQLite API, this function is not guaranteed to 7811** operate consistently from one release to the next. 7812*/ 7813int sqlite3_test_control(int op, ...); 7814 7815/* 7816** CAPI3REF: Testing Interface Operation Codes 7817** 7818** These constants are the valid operation code parameters used 7819** as the first argument to [sqlite3_test_control()]. 7820** 7821** These parameters and their meanings are subject to change 7822** without notice. These values are for testing purposes only. 7823** Applications should not use any of these parameters or the 7824** [sqlite3_test_control()] interface. 7825*/ 7826#define SQLITE_TESTCTRL_FIRST 5 7827#define SQLITE_TESTCTRL_PRNG_SAVE 5 7828#define SQLITE_TESTCTRL_PRNG_RESTORE 6 7829#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 7830#define SQLITE_TESTCTRL_BITVEC_TEST 8 7831#define SQLITE_TESTCTRL_FAULT_INSTALL 9 7832#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 7833#define SQLITE_TESTCTRL_PENDING_BYTE 11 7834#define SQLITE_TESTCTRL_ASSERT 12 7835#define SQLITE_TESTCTRL_ALWAYS 13 7836#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 7837#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 7838#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 7839#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 7840#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 7841#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 7842#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 7843#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 7844#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 7845#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 7846#define SQLITE_TESTCTRL_BYTEORDER 22 7847#define SQLITE_TESTCTRL_ISINIT 23 7848#define SQLITE_TESTCTRL_SORTER_MMAP 24 7849#define SQLITE_TESTCTRL_IMPOSTER 25 7850#define SQLITE_TESTCTRL_PARSER_COVERAGE 26 7851#define SQLITE_TESTCTRL_RESULT_INTREAL 27 7852#define SQLITE_TESTCTRL_PRNG_SEED 28 7853#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 7854#define SQLITE_TESTCTRL_SEEK_COUNT 30 7855#define SQLITE_TESTCTRL_TRACEFLAGS 31 7856#define SQLITE_TESTCTRL_TUNE 32 7857#define SQLITE_TESTCTRL_LAST 32 /* Largest TESTCTRL */ 7858 7859/* 7860** CAPI3REF: SQL Keyword Checking 7861** 7862** These routines provide access to the set of SQL language keywords 7863** recognized by SQLite. Applications can uses these routines to determine 7864** whether or not a specific identifier needs to be escaped (for example, 7865** by enclosing in double-quotes) so as not to confuse the parser. 7866** 7867** The sqlite3_keyword_count() interface returns the number of distinct 7868** keywords understood by SQLite. 7869** 7870** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and 7871** makes *Z point to that keyword expressed as UTF8 and writes the number 7872** of bytes in the keyword into *L. The string that *Z points to is not 7873** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 7874** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 7875** or L are NULL or invalid pointers then calls to 7876** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 7877** 7878** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 7879** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 7880** if it is and zero if not. 7881** 7882** The parser used by SQLite is forgiving. It is often possible to use 7883** a keyword as an identifier as long as such use does not result in a 7884** parsing ambiguity. For example, the statement 7885** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 7886** creates a new table named "BEGIN" with three columns named 7887** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 7888** using keywords as identifiers. Common techniques used to avoid keyword 7889** name collisions include: 7890** <ul> 7891** <li> Put all identifier names inside double-quotes. This is the official 7892** SQL way to escape identifier names. 7893** <li> Put identifier names inside [...]. This is not standard SQL, 7894** but it is what SQL Server does and so lots of programmers use this 7895** technique. 7896** <li> Begin every identifier with the letter "Z" as no SQL keywords start 7897** with "Z". 7898** <li> Include a digit somewhere in every identifier name. 7899** </ul> 7900** 7901** Note that the number of keywords understood by SQLite can depend on 7902** compile-time options. For example, "VACUUM" is not a keyword if 7903** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 7904** new keywords may be added to future releases of SQLite. 7905*/ 7906int sqlite3_keyword_count(void); 7907int sqlite3_keyword_name(int,const char**,int*); 7908int sqlite3_keyword_check(const char*,int); 7909 7910/* 7911** CAPI3REF: Dynamic String Object 7912** KEYWORDS: {dynamic string} 7913** 7914** An instance of the sqlite3_str object contains a dynamically-sized 7915** string under construction. 7916** 7917** The lifecycle of an sqlite3_str object is as follows: 7918** <ol> 7919** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 7920** <li> ^Text is appended to the sqlite3_str object using various 7921** methods, such as [sqlite3_str_appendf()]. 7922** <li> ^The sqlite3_str object is destroyed and the string it created 7923** is returned using the [sqlite3_str_finish()] interface. 7924** </ol> 7925*/ 7926typedef struct sqlite3_str sqlite3_str; 7927 7928/* 7929** CAPI3REF: Create A New Dynamic String Object 7930** CONSTRUCTOR: sqlite3_str 7931** 7932** ^The [sqlite3_str_new(D)] interface allocates and initializes 7933** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 7934** [sqlite3_str_new()] must be freed by a subsequent call to 7935** [sqlite3_str_finish(X)]. 7936** 7937** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 7938** valid [sqlite3_str] object, though in the event of an out-of-memory 7939** error the returned object might be a special singleton that will 7940** silently reject new text, always return SQLITE_NOMEM from 7941** [sqlite3_str_errcode()], always return 0 for 7942** [sqlite3_str_length()], and always return NULL from 7943** [sqlite3_str_finish(X)]. It is always safe to use the value 7944** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 7945** to any of the other [sqlite3_str] methods. 7946** 7947** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 7948** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 7949** length of the string contained in the [sqlite3_str] object will be 7950** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 7951** of [SQLITE_MAX_LENGTH]. 7952*/ 7953sqlite3_str *sqlite3_str_new(sqlite3*); 7954 7955/* 7956** CAPI3REF: Finalize A Dynamic String 7957** DESTRUCTOR: sqlite3_str 7958** 7959** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 7960** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 7961** that contains the constructed string. The calling application should 7962** pass the returned value to [sqlite3_free()] to avoid a memory leak. 7963** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 7964** errors were encountered during construction of the string. ^The 7965** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 7966** string in [sqlite3_str] object X is zero bytes long. 7967*/ 7968char *sqlite3_str_finish(sqlite3_str*); 7969 7970/* 7971** CAPI3REF: Add Content To A Dynamic String 7972** METHOD: sqlite3_str 7973** 7974** These interfaces add content to an sqlite3_str object previously obtained 7975** from [sqlite3_str_new()]. 7976** 7977** ^The [sqlite3_str_appendf(X,F,...)] and 7978** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 7979** functionality of SQLite to append formatted text onto the end of 7980** [sqlite3_str] object X. 7981** 7982** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 7983** onto the end of the [sqlite3_str] object X. N must be non-negative. 7984** S must contain at least N non-zero bytes of content. To append a 7985** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 7986** method instead. 7987** 7988** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 7989** zero-terminated string S onto the end of [sqlite3_str] object X. 7990** 7991** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 7992** single-byte character C onto the end of [sqlite3_str] object X. 7993** ^This method can be used, for example, to add whitespace indentation. 7994** 7995** ^The [sqlite3_str_reset(X)] method resets the string under construction 7996** inside [sqlite3_str] object X back to zero bytes in length. 7997** 7998** These methods do not return a result code. ^If an error occurs, that fact 7999** is recorded in the [sqlite3_str] object and can be recovered by a 8000** subsequent call to [sqlite3_str_errcode(X)]. 8001*/ 8002void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 8003void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 8004void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 8005void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 8006void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 8007void sqlite3_str_reset(sqlite3_str*); 8008 8009/* 8010** CAPI3REF: Status Of A Dynamic String 8011** METHOD: sqlite3_str 8012** 8013** These interfaces return the current status of an [sqlite3_str] object. 8014** 8015** ^If any prior errors have occurred while constructing the dynamic string 8016** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 8017** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 8018** [SQLITE_NOMEM] following any out-of-memory error, or 8019** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 8020** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 8021** 8022** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 8023** of the dynamic string under construction in [sqlite3_str] object X. 8024** ^The length returned by [sqlite3_str_length(X)] does not include the 8025** zero-termination byte. 8026** 8027** ^The [sqlite3_str_value(X)] method returns a pointer to the current 8028** content of the dynamic string under construction in X. The value 8029** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 8030** and might be freed or altered by any subsequent method on the same 8031** [sqlite3_str] object. Applications must not used the pointer returned 8032** [sqlite3_str_value(X)] after any subsequent method call on the same 8033** object. ^Applications may change the content of the string returned 8034** by [sqlite3_str_value(X)] as long as they do not write into any bytes 8035** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 8036** write any byte after any subsequent sqlite3_str method call. 8037*/ 8038int sqlite3_str_errcode(sqlite3_str*); 8039int sqlite3_str_length(sqlite3_str*); 8040char *sqlite3_str_value(sqlite3_str*); 8041 8042/* 8043** CAPI3REF: SQLite Runtime Status 8044** 8045** ^These interfaces are used to retrieve runtime status information 8046** about the performance of SQLite, and optionally to reset various 8047** highwater marks. ^The first argument is an integer code for 8048** the specific parameter to measure. ^(Recognized integer codes 8049** are of the form [status parameters | SQLITE_STATUS_...].)^ 8050** ^The current value of the parameter is returned into *pCurrent. 8051** ^The highest recorded value is returned in *pHighwater. ^If the 8052** resetFlag is true, then the highest record value is reset after 8053** *pHighwater is written. ^(Some parameters do not record the highest 8054** value. For those parameters 8055** nothing is written into *pHighwater and the resetFlag is ignored.)^ 8056** ^(Other parameters record only the highwater mark and not the current 8057** value. For these latter parameters nothing is written into *pCurrent.)^ 8058** 8059** ^The sqlite3_status() and sqlite3_status64() routines return 8060** SQLITE_OK on success and a non-zero [error code] on failure. 8061** 8062** If either the current value or the highwater mark is too large to 8063** be represented by a 32-bit integer, then the values returned by 8064** sqlite3_status() are undefined. 8065** 8066** See also: [sqlite3_db_status()] 8067*/ 8068int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 8069int sqlite3_status64( 8070 int op, 8071 sqlite3_int64 *pCurrent, 8072 sqlite3_int64 *pHighwater, 8073 int resetFlag 8074); 8075 8076 8077/* 8078** CAPI3REF: Status Parameters 8079** KEYWORDS: {status parameters} 8080** 8081** These integer constants designate various run-time status parameters 8082** that can be returned by [sqlite3_status()]. 8083** 8084** <dl> 8085** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8086** <dd>This parameter is the current amount of memory checked out 8087** using [sqlite3_malloc()], either directly or indirectly. The 8088** figure includes calls made to [sqlite3_malloc()] by the application 8089** and internal memory usage by the SQLite library. Auxiliary page-cache 8090** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8091** this parameter. The amount returned is the sum of the allocation 8092** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8093** 8094** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8095** <dd>This parameter records the largest memory allocation request 8096** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8097** internal equivalents). Only the value returned in the 8098** *pHighwater parameter to [sqlite3_status()] is of interest. 8099** The value written into the *pCurrent parameter is undefined.</dd>)^ 8100** 8101** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8102** <dd>This parameter records the number of separate memory allocations 8103** currently checked out.</dd>)^ 8104** 8105** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8106** <dd>This parameter returns the number of pages used out of the 8107** [pagecache memory allocator] that was configured using 8108** [SQLITE_CONFIG_PAGECACHE]. The 8109** value returned is in pages, not in bytes.</dd>)^ 8110** 8111** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8112** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8113** <dd>This parameter returns the number of bytes of page cache 8114** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8115** buffer and where forced to overflow to [sqlite3_malloc()]. The 8116** returned value includes allocations that overflowed because they 8117** where too large (they were larger than the "sz" parameter to 8118** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8119** no space was left in the page cache.</dd>)^ 8120** 8121** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 8122** <dd>This parameter records the largest memory allocation request 8123** handed to the [pagecache memory allocator]. Only the value returned in the 8124** *pHighwater parameter to [sqlite3_status()] is of interest. 8125** The value written into the *pCurrent parameter is undefined.</dd>)^ 8126** 8127** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 8128** <dd>No longer used.</dd> 8129** 8130** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 8131** <dd>No longer used.</dd> 8132** 8133** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 8134** <dd>No longer used.</dd> 8135** 8136** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 8137** <dd>The *pHighwater parameter records the deepest parser stack. 8138** The *pCurrent value is undefined. The *pHighwater value is only 8139** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 8140** </dl> 8141** 8142** New status parameters may be added from time to time. 8143*/ 8144#define SQLITE_STATUS_MEMORY_USED 0 8145#define SQLITE_STATUS_PAGECACHE_USED 1 8146#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 8147#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 8148#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 8149#define SQLITE_STATUS_MALLOC_SIZE 5 8150#define SQLITE_STATUS_PARSER_STACK 6 8151#define SQLITE_STATUS_PAGECACHE_SIZE 7 8152#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 8153#define SQLITE_STATUS_MALLOC_COUNT 9 8154 8155/* 8156** CAPI3REF: Database Connection Status 8157** METHOD: sqlite3 8158** 8159** ^This interface is used to retrieve runtime status information 8160** about a single [database connection]. ^The first argument is the 8161** database connection object to be interrogated. ^The second argument 8162** is an integer constant, taken from the set of 8163** [SQLITE_DBSTATUS options], that 8164** determines the parameter to interrogate. The set of 8165** [SQLITE_DBSTATUS options] is likely 8166** to grow in future releases of SQLite. 8167** 8168** ^The current value of the requested parameter is written into *pCur 8169** and the highest instantaneous value is written into *pHiwtr. ^If 8170** the resetFlg is true, then the highest instantaneous value is 8171** reset back down to the current value. 8172** 8173** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 8174** non-zero [error code] on failure. 8175** 8176** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 8177*/ 8178int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 8179 8180/* 8181** CAPI3REF: Status Parameters for database connections 8182** KEYWORDS: {SQLITE_DBSTATUS options} 8183** 8184** These constants are the available integer "verbs" that can be passed as 8185** the second argument to the [sqlite3_db_status()] interface. 8186** 8187** New verbs may be added in future releases of SQLite. Existing verbs 8188** might be discontinued. Applications should check the return code from 8189** [sqlite3_db_status()] to make sure that the call worked. 8190** The [sqlite3_db_status()] interface will return a non-zero error code 8191** if a discontinued or unsupported verb is invoked. 8192** 8193** <dl> 8194** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 8195** <dd>This parameter returns the number of lookaside memory slots currently 8196** checked out.</dd>)^ 8197** 8198** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 8199** <dd>This parameter returns the number of malloc attempts that were 8200** satisfied using lookaside memory. Only the high-water value is meaningful; 8201** the current value is always zero.)^ 8202** 8203** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 8204** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 8205** <dd>This parameter returns the number malloc attempts that might have 8206** been satisfied using lookaside memory but failed due to the amount of 8207** memory requested being larger than the lookaside slot size. 8208** Only the high-water value is meaningful; 8209** the current value is always zero.)^ 8210** 8211** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 8212** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 8213** <dd>This parameter returns the number malloc attempts that might have 8214** been satisfied using lookaside memory but failed due to all lookaside 8215** memory already being in use. 8216** Only the high-water value is meaningful; 8217** the current value is always zero.)^ 8218** 8219** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 8220** <dd>This parameter returns the approximate number of bytes of heap 8221** memory used by all pager caches associated with the database connection.)^ 8222** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 8223** 8224** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 8225** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 8226** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 8227** pager cache is shared between two or more connections the bytes of heap 8228** memory used by that pager cache is divided evenly between the attached 8229** connections.)^ In other words, if none of the pager caches associated 8230** with the database connection are shared, this request returns the same 8231** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8232** shared, the value returned by this call will be smaller than that returned 8233** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8234** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8235** 8236** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8237** <dd>This parameter returns the approximate number of bytes of heap 8238** memory used to store the schema for all databases associated 8239** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8240** ^The full amount of memory used by the schemas is reported, even if the 8241** schema memory is shared with other database connections due to 8242** [shared cache mode] being enabled. 8243** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8244** 8245** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8246** <dd>This parameter returns the approximate number of bytes of heap 8247** and lookaside memory used by all prepared statements associated with 8248** the database connection.)^ 8249** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8250** </dd> 8251** 8252** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8253** <dd>This parameter returns the number of pager cache hits that have 8254** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8255** is always 0. 8256** </dd> 8257** 8258** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8259** <dd>This parameter returns the number of pager cache misses that have 8260** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8261** is always 0. 8262** </dd> 8263** 8264** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8265** <dd>This parameter returns the number of dirty cache entries that have 8266** been written to disk. Specifically, the number of pages written to the 8267** wal file in wal mode databases, or the number of pages written to the 8268** database file in rollback mode databases. Any pages written as part of 8269** transaction rollback or database recovery operations are not included. 8270** If an IO or other error occurs while writing a page to disk, the effect 8271** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8272** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8273** </dd> 8274** 8275** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8276** <dd>This parameter returns the number of dirty cache entries that have 8277** been written to disk in the middle of a transaction due to the page 8278** cache overflowing. Transactions are more efficient if they are written 8279** to disk all at once. When pages spill mid-transaction, that introduces 8280** additional overhead. This parameter can be used help identify 8281** inefficiencies that can be resolved by increasing the cache size. 8282** </dd> 8283** 8284** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8285** <dd>This parameter returns zero for the current value if and only if 8286** all foreign key constraints (deferred or immediate) have been 8287** resolved.)^ ^The highwater mark is always 0. 8288** </dd> 8289** </dl> 8290*/ 8291#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8292#define SQLITE_DBSTATUS_CACHE_USED 1 8293#define SQLITE_DBSTATUS_SCHEMA_USED 2 8294#define SQLITE_DBSTATUS_STMT_USED 3 8295#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8296#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8297#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8298#define SQLITE_DBSTATUS_CACHE_HIT 7 8299#define SQLITE_DBSTATUS_CACHE_MISS 8 8300#define SQLITE_DBSTATUS_CACHE_WRITE 9 8301#define SQLITE_DBSTATUS_DEFERRED_FKS 10 8302#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8303#define SQLITE_DBSTATUS_CACHE_SPILL 12 8304#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8305 8306 8307/* 8308** CAPI3REF: Prepared Statement Status 8309** METHOD: sqlite3_stmt 8310** 8311** ^(Each prepared statement maintains various 8312** [SQLITE_STMTSTATUS counters] that measure the number 8313** of times it has performed specific operations.)^ These counters can 8314** be used to monitor the performance characteristics of the prepared 8315** statements. For example, if the number of table steps greatly exceeds 8316** the number of table searches or result rows, that would tend to indicate 8317** that the prepared statement is using a full table scan rather than 8318** an index. 8319** 8320** ^(This interface is used to retrieve and reset counter values from 8321** a [prepared statement]. The first argument is the prepared statement 8322** object to be interrogated. The second argument 8323** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8324** to be interrogated.)^ 8325** ^The current value of the requested counter is returned. 8326** ^If the resetFlg is true, then the counter is reset to zero after this 8327** interface call returns. 8328** 8329** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8330*/ 8331int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8332 8333/* 8334** CAPI3REF: Status Parameters for prepared statements 8335** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8336** 8337** These preprocessor macros define integer codes that name counter 8338** values associated with the [sqlite3_stmt_status()] interface. 8339** The meanings of the various counters are as follows: 8340** 8341** <dl> 8342** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8343** <dd>^This is the number of times that SQLite has stepped forward in 8344** a table as part of a full table scan. Large numbers for this counter 8345** may indicate opportunities for performance improvement through 8346** careful use of indices.</dd> 8347** 8348** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8349** <dd>^This is the number of sort operations that have occurred. 8350** A non-zero value in this counter may indicate an opportunity to 8351** improvement performance through careful use of indices.</dd> 8352** 8353** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8354** <dd>^This is the number of rows inserted into transient indices that 8355** were created automatically in order to help joins run faster. 8356** A non-zero value in this counter may indicate an opportunity to 8357** improvement performance by adding permanent indices that do not 8358** need to be reinitialized each time the statement is run.</dd> 8359** 8360** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8361** <dd>^This is the number of virtual machine operations executed 8362** by the prepared statement if that number is less than or equal 8363** to 2147483647. The number of virtual machine operations can be 8364** used as a proxy for the total work done by the prepared statement. 8365** If the number of virtual machine operations exceeds 2147483647 8366** then the value returned by this statement status code is undefined. 8367** 8368** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8369** <dd>^This is the number of times that the prepare statement has been 8370** automatically regenerated due to schema changes or changes to 8371** [bound parameters] that might affect the query plan. 8372** 8373** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8374** <dd>^This is the number of times that the prepared statement has 8375** been run. A single "run" for the purposes of this counter is one 8376** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8377** The counter is incremented on the first [sqlite3_step()] call of each 8378** cycle. 8379** 8380** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8381** <dd>^This is the approximate number of bytes of heap memory 8382** used to store the prepared statement. ^This value is not actually 8383** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8384** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8385** </dd> 8386** </dl> 8387*/ 8388#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8389#define SQLITE_STMTSTATUS_SORT 2 8390#define SQLITE_STMTSTATUS_AUTOINDEX 3 8391#define SQLITE_STMTSTATUS_VM_STEP 4 8392#define SQLITE_STMTSTATUS_REPREPARE 5 8393#define SQLITE_STMTSTATUS_RUN 6 8394#define SQLITE_STMTSTATUS_MEMUSED 99 8395 8396/* 8397** CAPI3REF: Custom Page Cache Object 8398** 8399** The sqlite3_pcache type is opaque. It is implemented by 8400** the pluggable module. The SQLite core has no knowledge of 8401** its size or internal structure and never deals with the 8402** sqlite3_pcache object except by holding and passing pointers 8403** to the object. 8404** 8405** See [sqlite3_pcache_methods2] for additional information. 8406*/ 8407typedef struct sqlite3_pcache sqlite3_pcache; 8408 8409/* 8410** CAPI3REF: Custom Page Cache Object 8411** 8412** The sqlite3_pcache_page object represents a single page in the 8413** page cache. The page cache will allocate instances of this 8414** object. Various methods of the page cache use pointers to instances 8415** of this object as parameters or as their return value. 8416** 8417** See [sqlite3_pcache_methods2] for additional information. 8418*/ 8419typedef struct sqlite3_pcache_page sqlite3_pcache_page; 8420struct sqlite3_pcache_page { 8421 void *pBuf; /* The content of the page */ 8422 void *pExtra; /* Extra information associated with the page */ 8423}; 8424 8425/* 8426** CAPI3REF: Application Defined Page Cache. 8427** KEYWORDS: {page cache} 8428** 8429** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8430** register an alternative page cache implementation by passing in an 8431** instance of the sqlite3_pcache_methods2 structure.)^ 8432** In many applications, most of the heap memory allocated by 8433** SQLite is used for the page cache. 8434** By implementing a 8435** custom page cache using this API, an application can better control 8436** the amount of memory consumed by SQLite, the way in which 8437** that memory is allocated and released, and the policies used to 8438** determine exactly which parts of a database file are cached and for 8439** how long. 8440** 8441** The alternative page cache mechanism is an 8442** extreme measure that is only needed by the most demanding applications. 8443** The built-in page cache is recommended for most uses. 8444** 8445** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8446** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8447** the application may discard the parameter after the call to 8448** [sqlite3_config()] returns.)^ 8449** 8450** [[the xInit() page cache method]] 8451** ^(The xInit() method is called once for each effective 8452** call to [sqlite3_initialize()])^ 8453** (usually only once during the lifetime of the process). ^(The xInit() 8454** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8455** The intent of the xInit() method is to set up global data structures 8456** required by the custom page cache implementation. 8457** ^(If the xInit() method is NULL, then the 8458** built-in default page cache is used instead of the application defined 8459** page cache.)^ 8460** 8461** [[the xShutdown() page cache method]] 8462** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8463** It can be used to clean up 8464** any outstanding resources before process shutdown, if required. 8465** ^The xShutdown() method may be NULL. 8466** 8467** ^SQLite automatically serializes calls to the xInit method, 8468** so the xInit method need not be threadsafe. ^The 8469** xShutdown method is only called from [sqlite3_shutdown()] so it does 8470** not need to be threadsafe either. All other methods must be threadsafe 8471** in multithreaded applications. 8472** 8473** ^SQLite will never invoke xInit() more than once without an intervening 8474** call to xShutdown(). 8475** 8476** [[the xCreate() page cache methods]] 8477** ^SQLite invokes the xCreate() method to construct a new cache instance. 8478** SQLite will typically create one cache instance for each open database file, 8479** though this is not guaranteed. ^The 8480** first parameter, szPage, is the size in bytes of the pages that must 8481** be allocated by the cache. ^szPage will always a power of two. ^The 8482** second parameter szExtra is a number of bytes of extra storage 8483** associated with each page cache entry. ^The szExtra parameter will 8484** a number less than 250. SQLite will use the 8485** extra szExtra bytes on each page to store metadata about the underlying 8486** database page on disk. The value passed into szExtra depends 8487** on the SQLite version, the target platform, and how SQLite was compiled. 8488** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8489** created will be used to cache database pages of a file stored on disk, or 8490** false if it is used for an in-memory database. The cache implementation 8491** does not have to do anything special based with the value of bPurgeable; 8492** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 8493** never invoke xUnpin() except to deliberately delete a page. 8494** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 8495** false will always have the "discard" flag set to true. 8496** ^Hence, a cache created with bPurgeable false will 8497** never contain any unpinned pages. 8498** 8499** [[the xCachesize() page cache method]] 8500** ^(The xCachesize() method may be called at any time by SQLite to set the 8501** suggested maximum cache-size (number of pages stored by) the cache 8502** instance passed as the first argument. This is the value configured using 8503** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 8504** parameter, the implementation is not required to do anything with this 8505** value; it is advisory only. 8506** 8507** [[the xPagecount() page cache methods]] 8508** The xPagecount() method must return the number of pages currently 8509** stored in the cache, both pinned and unpinned. 8510** 8511** [[the xFetch() page cache methods]] 8512** The xFetch() method locates a page in the cache and returns a pointer to 8513** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 8514** The pBuf element of the returned sqlite3_pcache_page object will be a 8515** pointer to a buffer of szPage bytes used to store the content of a 8516** single database page. The pExtra element of sqlite3_pcache_page will be 8517** a pointer to the szExtra bytes of extra storage that SQLite has requested 8518** for each entry in the page cache. 8519** 8520** The page to be fetched is determined by the key. ^The minimum key value 8521** is 1. After it has been retrieved using xFetch, the page is considered 8522** to be "pinned". 8523** 8524** If the requested page is already in the page cache, then the page cache 8525** implementation must return a pointer to the page buffer with its content 8526** intact. If the requested page is not already in the cache, then the 8527** cache implementation should use the value of the createFlag 8528** parameter to help it determined what action to take: 8529** 8530** <table border=1 width=85% align=center> 8531** <tr><th> createFlag <th> Behavior when page is not already in cache 8532** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 8533** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 8534** Otherwise return NULL. 8535** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 8536** NULL if allocating a new page is effectively impossible. 8537** </table> 8538** 8539** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 8540** will only use a createFlag of 2 after a prior call with a createFlag of 1 8541** failed.)^ In between the xFetch() calls, SQLite may 8542** attempt to unpin one or more cache pages by spilling the content of 8543** pinned pages to disk and synching the operating system disk cache. 8544** 8545** [[the xUnpin() page cache method]] 8546** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 8547** as its second argument. If the third parameter, discard, is non-zero, 8548** then the page must be evicted from the cache. 8549** ^If the discard parameter is 8550** zero, then the page may be discarded or retained at the discretion of 8551** page cache implementation. ^The page cache implementation 8552** may choose to evict unpinned pages at any time. 8553** 8554** The cache must not perform any reference counting. A single 8555** call to xUnpin() unpins the page regardless of the number of prior calls 8556** to xFetch(). 8557** 8558** [[the xRekey() page cache methods]] 8559** The xRekey() method is used to change the key value associated with the 8560** page passed as the second argument. If the cache 8561** previously contains an entry associated with newKey, it must be 8562** discarded. ^Any prior cache entry associated with newKey is guaranteed not 8563** to be pinned. 8564** 8565** When SQLite calls the xTruncate() method, the cache must discard all 8566** existing cache entries with page numbers (keys) greater than or equal 8567** to the value of the iLimit parameter passed to xTruncate(). If any 8568** of these pages are pinned, they are implicitly unpinned, meaning that 8569** they can be safely discarded. 8570** 8571** [[the xDestroy() page cache method]] 8572** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 8573** All resources associated with the specified cache should be freed. ^After 8574** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 8575** handle invalid, and will not use it with any other sqlite3_pcache_methods2 8576** functions. 8577** 8578** [[the xShrink() page cache method]] 8579** ^SQLite invokes the xShrink() method when it wants the page cache to 8580** free up as much of heap memory as possible. The page cache implementation 8581** is not obligated to free any memory, but well-behaved implementations should 8582** do their best. 8583*/ 8584typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 8585struct sqlite3_pcache_methods2 { 8586 int iVersion; 8587 void *pArg; 8588 int (*xInit)(void*); 8589 void (*xShutdown)(void*); 8590 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 8591 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8592 int (*xPagecount)(sqlite3_pcache*); 8593 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8594 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 8595 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 8596 unsigned oldKey, unsigned newKey); 8597 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8598 void (*xDestroy)(sqlite3_pcache*); 8599 void (*xShrink)(sqlite3_pcache*); 8600}; 8601 8602/* 8603** This is the obsolete pcache_methods object that has now been replaced 8604** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 8605** retained in the header file for backwards compatibility only. 8606*/ 8607typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 8608struct sqlite3_pcache_methods { 8609 void *pArg; 8610 int (*xInit)(void*); 8611 void (*xShutdown)(void*); 8612 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 8613 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8614 int (*xPagecount)(sqlite3_pcache*); 8615 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8616 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 8617 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 8618 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8619 void (*xDestroy)(sqlite3_pcache*); 8620}; 8621 8622 8623/* 8624** CAPI3REF: Online Backup Object 8625** 8626** The sqlite3_backup object records state information about an ongoing 8627** online backup operation. ^The sqlite3_backup object is created by 8628** a call to [sqlite3_backup_init()] and is destroyed by a call to 8629** [sqlite3_backup_finish()]. 8630** 8631** See Also: [Using the SQLite Online Backup API] 8632*/ 8633typedef struct sqlite3_backup sqlite3_backup; 8634 8635/* 8636** CAPI3REF: Online Backup API. 8637** 8638** The backup API copies the content of one database into another. 8639** It is useful either for creating backups of databases or 8640** for copying in-memory databases to or from persistent files. 8641** 8642** See Also: [Using the SQLite Online Backup API] 8643** 8644** ^SQLite holds a write transaction open on the destination database file 8645** for the duration of the backup operation. 8646** ^The source database is read-locked only while it is being read; 8647** it is not locked continuously for the entire backup operation. 8648** ^Thus, the backup may be performed on a live source database without 8649** preventing other database connections from 8650** reading or writing to the source database while the backup is underway. 8651** 8652** ^(To perform a backup operation: 8653** <ol> 8654** <li><b>sqlite3_backup_init()</b> is called once to initialize the 8655** backup, 8656** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 8657** the data between the two databases, and finally 8658** <li><b>sqlite3_backup_finish()</b> is called to release all resources 8659** associated with the backup operation. 8660** </ol>)^ 8661** There should be exactly one call to sqlite3_backup_finish() for each 8662** successful call to sqlite3_backup_init(). 8663** 8664** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 8665** 8666** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 8667** [database connection] associated with the destination database 8668** and the database name, respectively. 8669** ^The database name is "main" for the main database, "temp" for the 8670** temporary database, or the name specified after the AS keyword in 8671** an [ATTACH] statement for an attached database. 8672** ^The S and M arguments passed to 8673** sqlite3_backup_init(D,N,S,M) identify the [database connection] 8674** and database name of the source database, respectively. 8675** ^The source and destination [database connections] (parameters S and D) 8676** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 8677** an error. 8678** 8679** ^A call to sqlite3_backup_init() will fail, returning NULL, if 8680** there is already a read or read-write transaction open on the 8681** destination database. 8682** 8683** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 8684** returned and an error code and error message are stored in the 8685** destination [database connection] D. 8686** ^The error code and message for the failed call to sqlite3_backup_init() 8687** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 8688** [sqlite3_errmsg16()] functions. 8689** ^A successful call to sqlite3_backup_init() returns a pointer to an 8690** [sqlite3_backup] object. 8691** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 8692** sqlite3_backup_finish() functions to perform the specified backup 8693** operation. 8694** 8695** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 8696** 8697** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 8698** the source and destination databases specified by [sqlite3_backup] object B. 8699** ^If N is negative, all remaining source pages are copied. 8700** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 8701** are still more pages to be copied, then the function returns [SQLITE_OK]. 8702** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 8703** from source to destination, then it returns [SQLITE_DONE]. 8704** ^If an error occurs while running sqlite3_backup_step(B,N), 8705** then an [error code] is returned. ^As well as [SQLITE_OK] and 8706** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 8707** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 8708** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 8709** 8710** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 8711** <ol> 8712** <li> the destination database was opened read-only, or 8713** <li> the destination database is using write-ahead-log journaling 8714** and the destination and source page sizes differ, or 8715** <li> the destination database is an in-memory database and the 8716** destination and source page sizes differ. 8717** </ol>)^ 8718** 8719** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 8720** the [sqlite3_busy_handler | busy-handler function] 8721** is invoked (if one is specified). ^If the 8722** busy-handler returns non-zero before the lock is available, then 8723** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 8724** sqlite3_backup_step() can be retried later. ^If the source 8725** [database connection] 8726** is being used to write to the source database when sqlite3_backup_step() 8727** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 8728** case the call to sqlite3_backup_step() can be retried later on. ^(If 8729** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 8730** [SQLITE_READONLY] is returned, then 8731** there is no point in retrying the call to sqlite3_backup_step(). These 8732** errors are considered fatal.)^ The application must accept 8733** that the backup operation has failed and pass the backup operation handle 8734** to the sqlite3_backup_finish() to release associated resources. 8735** 8736** ^The first call to sqlite3_backup_step() obtains an exclusive lock 8737** on the destination file. ^The exclusive lock is not released until either 8738** sqlite3_backup_finish() is called or the backup operation is complete 8739** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 8740** sqlite3_backup_step() obtains a [shared lock] on the source database that 8741** lasts for the duration of the sqlite3_backup_step() call. 8742** ^Because the source database is not locked between calls to 8743** sqlite3_backup_step(), the source database may be modified mid-way 8744** through the backup process. ^If the source database is modified by an 8745** external process or via a database connection other than the one being 8746** used by the backup operation, then the backup will be automatically 8747** restarted by the next call to sqlite3_backup_step(). ^If the source 8748** database is modified by the using the same database connection as is used 8749** by the backup operation, then the backup database is automatically 8750** updated at the same time. 8751** 8752** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 8753** 8754** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 8755** application wishes to abandon the backup operation, the application 8756** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 8757** ^The sqlite3_backup_finish() interfaces releases all 8758** resources associated with the [sqlite3_backup] object. 8759** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 8760** active write-transaction on the destination database is rolled back. 8761** The [sqlite3_backup] object is invalid 8762** and may not be used following a call to sqlite3_backup_finish(). 8763** 8764** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 8765** sqlite3_backup_step() errors occurred, regardless or whether or not 8766** sqlite3_backup_step() completed. 8767** ^If an out-of-memory condition or IO error occurred during any prior 8768** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 8769** sqlite3_backup_finish() returns the corresponding [error code]. 8770** 8771** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 8772** is not a permanent error and does not affect the return value of 8773** sqlite3_backup_finish(). 8774** 8775** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 8776** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 8777** 8778** ^The sqlite3_backup_remaining() routine returns the number of pages still 8779** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 8780** ^The sqlite3_backup_pagecount() routine returns the total number of pages 8781** in the source database at the conclusion of the most recent 8782** sqlite3_backup_step(). 8783** ^(The values returned by these functions are only updated by 8784** sqlite3_backup_step(). If the source database is modified in a way that 8785** changes the size of the source database or the number of pages remaining, 8786** those changes are not reflected in the output of sqlite3_backup_pagecount() 8787** and sqlite3_backup_remaining() until after the next 8788** sqlite3_backup_step().)^ 8789** 8790** <b>Concurrent Usage of Database Handles</b> 8791** 8792** ^The source [database connection] may be used by the application for other 8793** purposes while a backup operation is underway or being initialized. 8794** ^If SQLite is compiled and configured to support threadsafe database 8795** connections, then the source database connection may be used concurrently 8796** from within other threads. 8797** 8798** However, the application must guarantee that the destination 8799** [database connection] is not passed to any other API (by any thread) after 8800** sqlite3_backup_init() is called and before the corresponding call to 8801** sqlite3_backup_finish(). SQLite does not currently check to see 8802** if the application incorrectly accesses the destination [database connection] 8803** and so no error code is reported, but the operations may malfunction 8804** nevertheless. Use of the destination database connection while a 8805** backup is in progress might also also cause a mutex deadlock. 8806** 8807** If running in [shared cache mode], the application must 8808** guarantee that the shared cache used by the destination database 8809** is not accessed while the backup is running. In practice this means 8810** that the application must guarantee that the disk file being 8811** backed up to is not accessed by any connection within the process, 8812** not just the specific connection that was passed to sqlite3_backup_init(). 8813** 8814** The [sqlite3_backup] object itself is partially threadsafe. Multiple 8815** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 8816** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 8817** APIs are not strictly speaking threadsafe. If they are invoked at the 8818** same time as another thread is invoking sqlite3_backup_step() it is 8819** possible that they return invalid values. 8820*/ 8821sqlite3_backup *sqlite3_backup_init( 8822 sqlite3 *pDest, /* Destination database handle */ 8823 const char *zDestName, /* Destination database name */ 8824 sqlite3 *pSource, /* Source database handle */ 8825 const char *zSourceName /* Source database name */ 8826); 8827int sqlite3_backup_step(sqlite3_backup *p, int nPage); 8828int sqlite3_backup_finish(sqlite3_backup *p); 8829int sqlite3_backup_remaining(sqlite3_backup *p); 8830int sqlite3_backup_pagecount(sqlite3_backup *p); 8831 8832/* 8833** CAPI3REF: Unlock Notification 8834** METHOD: sqlite3 8835** 8836** ^When running in shared-cache mode, a database operation may fail with 8837** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 8838** individual tables within the shared-cache cannot be obtained. See 8839** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 8840** ^This API may be used to register a callback that SQLite will invoke 8841** when the connection currently holding the required lock relinquishes it. 8842** ^This API is only available if the library was compiled with the 8843** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 8844** 8845** See Also: [Using the SQLite Unlock Notification Feature]. 8846** 8847** ^Shared-cache locks are released when a database connection concludes 8848** its current transaction, either by committing it or rolling it back. 8849** 8850** ^When a connection (known as the blocked connection) fails to obtain a 8851** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 8852** identity of the database connection (the blocking connection) that 8853** has locked the required resource is stored internally. ^After an 8854** application receives an SQLITE_LOCKED error, it may call the 8855** sqlite3_unlock_notify() method with the blocked connection handle as 8856** the first argument to register for a callback that will be invoked 8857** when the blocking connections current transaction is concluded. ^The 8858** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 8859** call that concludes the blocking connection's transaction. 8860** 8861** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 8862** there is a chance that the blocking connection will have already 8863** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 8864** If this happens, then the specified callback is invoked immediately, 8865** from within the call to sqlite3_unlock_notify().)^ 8866** 8867** ^If the blocked connection is attempting to obtain a write-lock on a 8868** shared-cache table, and more than one other connection currently holds 8869** a read-lock on the same table, then SQLite arbitrarily selects one of 8870** the other connections to use as the blocking connection. 8871** 8872** ^(There may be at most one unlock-notify callback registered by a 8873** blocked connection. If sqlite3_unlock_notify() is called when the 8874** blocked connection already has a registered unlock-notify callback, 8875** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 8876** called with a NULL pointer as its second argument, then any existing 8877** unlock-notify callback is canceled. ^The blocked connections 8878** unlock-notify callback may also be canceled by closing the blocked 8879** connection using [sqlite3_close()]. 8880** 8881** The unlock-notify callback is not reentrant. If an application invokes 8882** any sqlite3_xxx API functions from within an unlock-notify callback, a 8883** crash or deadlock may be the result. 8884** 8885** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 8886** returns SQLITE_OK. 8887** 8888** <b>Callback Invocation Details</b> 8889** 8890** When an unlock-notify callback is registered, the application provides a 8891** single void* pointer that is passed to the callback when it is invoked. 8892** However, the signature of the callback function allows SQLite to pass 8893** it an array of void* context pointers. The first argument passed to 8894** an unlock-notify callback is a pointer to an array of void* pointers, 8895** and the second is the number of entries in the array. 8896** 8897** When a blocking connection's transaction is concluded, there may be 8898** more than one blocked connection that has registered for an unlock-notify 8899** callback. ^If two or more such blocked connections have specified the 8900** same callback function, then instead of invoking the callback function 8901** multiple times, it is invoked once with the set of void* context pointers 8902** specified by the blocked connections bundled together into an array. 8903** This gives the application an opportunity to prioritize any actions 8904** related to the set of unblocked database connections. 8905** 8906** <b>Deadlock Detection</b> 8907** 8908** Assuming that after registering for an unlock-notify callback a 8909** database waits for the callback to be issued before taking any further 8910** action (a reasonable assumption), then using this API may cause the 8911** application to deadlock. For example, if connection X is waiting for 8912** connection Y's transaction to be concluded, and similarly connection 8913** Y is waiting on connection X's transaction, then neither connection 8914** will proceed and the system may remain deadlocked indefinitely. 8915** 8916** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 8917** detection. ^If a given call to sqlite3_unlock_notify() would put the 8918** system in a deadlocked state, then SQLITE_LOCKED is returned and no 8919** unlock-notify callback is registered. The system is said to be in 8920** a deadlocked state if connection A has registered for an unlock-notify 8921** callback on the conclusion of connection B's transaction, and connection 8922** B has itself registered for an unlock-notify callback when connection 8923** A's transaction is concluded. ^Indirect deadlock is also detected, so 8924** the system is also considered to be deadlocked if connection B has 8925** registered for an unlock-notify callback on the conclusion of connection 8926** C's transaction, where connection C is waiting on connection A. ^Any 8927** number of levels of indirection are allowed. 8928** 8929** <b>The "DROP TABLE" Exception</b> 8930** 8931** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 8932** always appropriate to call sqlite3_unlock_notify(). There is however, 8933** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 8934** SQLite checks if there are any currently executing SELECT statements 8935** that belong to the same connection. If there are, SQLITE_LOCKED is 8936** returned. In this case there is no "blocking connection", so invoking 8937** sqlite3_unlock_notify() results in the unlock-notify callback being 8938** invoked immediately. If the application then re-attempts the "DROP TABLE" 8939** or "DROP INDEX" query, an infinite loop might be the result. 8940** 8941** One way around this problem is to check the extended error code returned 8942** by an sqlite3_step() call. ^(If there is a blocking connection, then the 8943** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 8944** the special "DROP TABLE/INDEX" case, the extended error code is just 8945** SQLITE_LOCKED.)^ 8946*/ 8947int sqlite3_unlock_notify( 8948 sqlite3 *pBlocked, /* Waiting connection */ 8949 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 8950 void *pNotifyArg /* Argument to pass to xNotify */ 8951); 8952 8953 8954/* 8955** CAPI3REF: String Comparison 8956** 8957** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 8958** and extensions to compare the contents of two buffers containing UTF-8 8959** strings in a case-independent fashion, using the same definition of "case 8960** independence" that SQLite uses internally when comparing identifiers. 8961*/ 8962int sqlite3_stricmp(const char *, const char *); 8963int sqlite3_strnicmp(const char *, const char *, int); 8964 8965/* 8966** CAPI3REF: String Globbing 8967* 8968** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 8969** string X matches the [GLOB] pattern P. 8970** ^The definition of [GLOB] pattern matching used in 8971** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 8972** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 8973** is case sensitive. 8974** 8975** Note that this routine returns zero on a match and non-zero if the strings 8976** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 8977** 8978** See also: [sqlite3_strlike()]. 8979*/ 8980int sqlite3_strglob(const char *zGlob, const char *zStr); 8981 8982/* 8983** CAPI3REF: String LIKE Matching 8984* 8985** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 8986** string X matches the [LIKE] pattern P with escape character E. 8987** ^The definition of [LIKE] pattern matching used in 8988** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 8989** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 8990** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 8991** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 8992** insensitive - equivalent upper and lower case ASCII characters match 8993** one another. 8994** 8995** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 8996** only ASCII characters are case folded. 8997** 8998** Note that this routine returns zero on a match and non-zero if the strings 8999** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9000** 9001** See also: [sqlite3_strglob()]. 9002*/ 9003int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 9004 9005/* 9006** CAPI3REF: Error Logging Interface 9007** 9008** ^The [sqlite3_log()] interface writes a message into the [error log] 9009** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 9010** ^If logging is enabled, the zFormat string and subsequent arguments are 9011** used with [sqlite3_snprintf()] to generate the final output string. 9012** 9013** The sqlite3_log() interface is intended for use by extensions such as 9014** virtual tables, collating functions, and SQL functions. While there is 9015** nothing to prevent an application from calling sqlite3_log(), doing so 9016** is considered bad form. 9017** 9018** The zFormat string must not be NULL. 9019** 9020** To avoid deadlocks and other threading problems, the sqlite3_log() routine 9021** will not use dynamically allocated memory. The log message is stored in 9022** a fixed-length buffer on the stack. If the log message is longer than 9023** a few hundred characters, it will be truncated to the length of the 9024** buffer. 9025*/ 9026void sqlite3_log(int iErrCode, const char *zFormat, ...); 9027 9028/* 9029** CAPI3REF: Write-Ahead Log Commit Hook 9030** METHOD: sqlite3 9031** 9032** ^The [sqlite3_wal_hook()] function is used to register a callback that 9033** is invoked each time data is committed to a database in wal mode. 9034** 9035** ^(The callback is invoked by SQLite after the commit has taken place and 9036** the associated write-lock on the database released)^, so the implementation 9037** may read, write or [checkpoint] the database as required. 9038** 9039** ^The first parameter passed to the callback function when it is invoked 9040** is a copy of the third parameter passed to sqlite3_wal_hook() when 9041** registering the callback. ^The second is a copy of the database handle. 9042** ^The third parameter is the name of the database that was written to - 9043** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 9044** is the number of pages currently in the write-ahead log file, 9045** including those that were just committed. 9046** 9047** The callback function should normally return [SQLITE_OK]. ^If an error 9048** code is returned, that error will propagate back up through the 9049** SQLite code base to cause the statement that provoked the callback 9050** to report an error, though the commit will have still occurred. If the 9051** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 9052** that does not correspond to any valid SQLite error code, the results 9053** are undefined. 9054** 9055** A single database handle may have at most a single write-ahead log callback 9056** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 9057** previously registered write-ahead log callback. ^The return value is 9058** a copy of the third parameter from the previous call, if any, or 0. 9059** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the 9060** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 9061** overwrite any prior [sqlite3_wal_hook()] settings. 9062*/ 9063void *sqlite3_wal_hook( 9064 sqlite3*, 9065 int(*)(void *,sqlite3*,const char*,int), 9066 void* 9067); 9068 9069/* 9070** CAPI3REF: Configure an auto-checkpoint 9071** METHOD: sqlite3 9072** 9073** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 9074** [sqlite3_wal_hook()] that causes any database on [database connection] D 9075** to automatically [checkpoint] 9076** after committing a transaction if there are N or 9077** more frames in the [write-ahead log] file. ^Passing zero or 9078** a negative value as the nFrame parameter disables automatic 9079** checkpoints entirely. 9080** 9081** ^The callback registered by this function replaces any existing callback 9082** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 9083** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 9084** configured by this function. 9085** 9086** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 9087** from SQL. 9088** 9089** ^Checkpoints initiated by this mechanism are 9090** [sqlite3_wal_checkpoint_v2|PASSIVE]. 9091** 9092** ^Every new [database connection] defaults to having the auto-checkpoint 9093** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 9094** pages. The use of this interface 9095** is only necessary if the default setting is found to be suboptimal 9096** for a particular application. 9097*/ 9098int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 9099 9100/* 9101** CAPI3REF: Checkpoint a database 9102** METHOD: sqlite3 9103** 9104** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 9105** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 9106** 9107** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 9108** [write-ahead log] for database X on [database connection] D to be 9109** transferred into the database file and for the write-ahead log to 9110** be reset. See the [checkpointing] documentation for addition 9111** information. 9112** 9113** This interface used to be the only way to cause a checkpoint to 9114** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 9115** interface was added. This interface is retained for backwards 9116** compatibility and as a convenience for applications that need to manually 9117** start a callback but which do not need the full power (and corresponding 9118** complication) of [sqlite3_wal_checkpoint_v2()]. 9119*/ 9120int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 9121 9122/* 9123** CAPI3REF: Checkpoint a database 9124** METHOD: sqlite3 9125** 9126** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 9127** operation on database X of [database connection] D in mode M. Status 9128** information is written back into integers pointed to by L and C.)^ 9129** ^(The M parameter must be a valid [checkpoint mode]:)^ 9130** 9131** <dl> 9132** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 9133** ^Checkpoint as many frames as possible without waiting for any database 9134** readers or writers to finish, then sync the database file if all frames 9135** in the log were checkpointed. ^The [busy-handler callback] 9136** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 9137** ^On the other hand, passive mode might leave the checkpoint unfinished 9138** if there are concurrent readers or writers. 9139** 9140** <dt>SQLITE_CHECKPOINT_FULL<dd> 9141** ^This mode blocks (it invokes the 9142** [sqlite3_busy_handler|busy-handler callback]) until there is no 9143** database writer and all readers are reading from the most recent database 9144** snapshot. ^It then checkpoints all frames in the log file and syncs the 9145** database file. ^This mode blocks new database writers while it is pending, 9146** but new database readers are allowed to continue unimpeded. 9147** 9148** <dt>SQLITE_CHECKPOINT_RESTART<dd> 9149** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 9150** that after checkpointing the log file it blocks (calls the 9151** [busy-handler callback]) 9152** until all readers are reading from the database file only. ^This ensures 9153** that the next writer will restart the log file from the beginning. 9154** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 9155** database writer attempts while it is pending, but does not impede readers. 9156** 9157** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 9158** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 9159** addition that it also truncates the log file to zero bytes just prior 9160** to a successful return. 9161** </dl> 9162** 9163** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 9164** the log file or to -1 if the checkpoint could not run because 9165** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 9166** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 9167** log file (including any that were already checkpointed before the function 9168** was called) or to -1 if the checkpoint could not run due to an error or 9169** because the database is not in WAL mode. ^Note that upon successful 9170** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 9171** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 9172** 9173** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 9174** any other process is running a checkpoint operation at the same time, the 9175** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 9176** busy-handler configured, it will not be invoked in this case. 9177** 9178** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 9179** exclusive "writer" lock on the database file. ^If the writer lock cannot be 9180** obtained immediately, and a busy-handler is configured, it is invoked and 9181** the writer lock retried until either the busy-handler returns 0 or the lock 9182** is successfully obtained. ^The busy-handler is also invoked while waiting for 9183** database readers as described above. ^If the busy-handler returns 0 before 9184** the writer lock is obtained or while waiting for database readers, the 9185** checkpoint operation proceeds from that point in the same way as 9186** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 9187** without blocking any further. ^SQLITE_BUSY is returned in this case. 9188** 9189** ^If parameter zDb is NULL or points to a zero length string, then the 9190** specified operation is attempted on all WAL databases [attached] to 9191** [database connection] db. In this case the 9192** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 9193** an SQLITE_BUSY error is encountered when processing one or more of the 9194** attached WAL databases, the operation is still attempted on any remaining 9195** attached databases and SQLITE_BUSY is returned at the end. ^If any other 9196** error occurs while processing an attached database, processing is abandoned 9197** and the error code is returned to the caller immediately. ^If no error 9198** (SQLITE_BUSY or otherwise) is encountered while processing the attached 9199** databases, SQLITE_OK is returned. 9200** 9201** ^If database zDb is the name of an attached database that is not in WAL 9202** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 9203** zDb is not NULL (or a zero length string) and is not the name of any 9204** attached database, SQLITE_ERROR is returned to the caller. 9205** 9206** ^Unless it returns SQLITE_MISUSE, 9207** the sqlite3_wal_checkpoint_v2() interface 9208** sets the error information that is queried by 9209** [sqlite3_errcode()] and [sqlite3_errmsg()]. 9210** 9211** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 9212** from SQL. 9213*/ 9214int sqlite3_wal_checkpoint_v2( 9215 sqlite3 *db, /* Database handle */ 9216 const char *zDb, /* Name of attached database (or NULL) */ 9217 int eMode, /* SQLITE_CHECKPOINT_* value */ 9218 int *pnLog, /* OUT: Size of WAL log in frames */ 9219 int *pnCkpt /* OUT: Total number of frames checkpointed */ 9220); 9221 9222/* 9223** CAPI3REF: Checkpoint Mode Values 9224** KEYWORDS: {checkpoint mode} 9225** 9226** These constants define all valid values for the "checkpoint mode" passed 9227** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 9228** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 9229** meaning of each of these checkpoint modes. 9230*/ 9231#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9232#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9233#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ 9234#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9235 9236/* 9237** CAPI3REF: Virtual Table Interface Configuration 9238** 9239** This function may be called by either the [xConnect] or [xCreate] method 9240** of a [virtual table] implementation to configure 9241** various facets of the virtual table interface. 9242** 9243** If this interface is invoked outside the context of an xConnect or 9244** xCreate virtual table method then the behavior is undefined. 9245** 9246** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9247** [database connection] in which the virtual table is being created and 9248** which is passed in as the first argument to the [xConnect] or [xCreate] 9249** method that is invoking sqlite3_vtab_config(). The C parameter is one 9250** of the [virtual table configuration options]. The presence and meaning 9251** of parameters after C depend on which [virtual table configuration option] 9252** is used. 9253*/ 9254int sqlite3_vtab_config(sqlite3*, int op, ...); 9255 9256/* 9257** CAPI3REF: Virtual Table Configuration Options 9258** KEYWORDS: {virtual table configuration options} 9259** KEYWORDS: {virtual table configuration option} 9260** 9261** These macros define the various options to the 9262** [sqlite3_vtab_config()] interface that [virtual table] implementations 9263** can use to customize and optimize their behavior. 9264** 9265** <dl> 9266** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9267** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9268** <dd>Calls of the form 9269** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9270** where X is an integer. If X is zero, then the [virtual table] whose 9271** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9272** support constraints. In this configuration (which is the default) if 9273** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9274** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9275** specified as part of the users SQL statement, regardless of the actual 9276** ON CONFLICT mode specified. 9277** 9278** If X is non-zero, then the virtual table implementation guarantees 9279** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9280** any modifications to internal or persistent data structures have been made. 9281** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9282** is able to roll back a statement or database transaction, and abandon 9283** or continue processing the current SQL statement as appropriate. 9284** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9285** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9286** had been ABORT. 9287** 9288** Virtual table implementations that are required to handle OR REPLACE 9289** must do so within the [xUpdate] method. If a call to the 9290** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9291** CONFLICT policy is REPLACE, the virtual table implementation should 9292** silently replace the appropriate rows within the xUpdate callback and 9293** return SQLITE_OK. Or, if this is not possible, it may return 9294** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9295** constraint handling. 9296** </dd> 9297** 9298** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9299** <dd>Calls of the form 9300** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9301** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9302** prohibits that virtual table from being used from within triggers and 9303** views. 9304** </dd> 9305** 9306** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9307** <dd>Calls of the form 9308** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9309** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9310** identify that virtual table as being safe to use from within triggers 9311** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9312** virtual table can do no serious harm even if it is controlled by a 9313** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9314** flag unless absolutely necessary. 9315** </dd> 9316** </dl> 9317*/ 9318#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9319#define SQLITE_VTAB_INNOCUOUS 2 9320#define SQLITE_VTAB_DIRECTONLY 3 9321 9322/* 9323** CAPI3REF: Determine The Virtual Table Conflict Policy 9324** 9325** This function may only be called from within a call to the [xUpdate] method 9326** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9327** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9328** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9329** of the SQL statement that triggered the call to the [xUpdate] method of the 9330** [virtual table]. 9331*/ 9332int sqlite3_vtab_on_conflict(sqlite3 *); 9333 9334/* 9335** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9336** 9337** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9338** method of a [virtual table], then it might return true if the 9339** column is being fetched as part of an UPDATE operation during which the 9340** column value will not change. The virtual table implementation can use 9341** this hint as permission to substitute a return value that is less 9342** expensive to compute and that the corresponding 9343** [xUpdate] method understands as a "no-change" value. 9344** 9345** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9346** the column is not changed by the UPDATE statement, then the xColumn 9347** method can optionally return without setting a result, without calling 9348** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9349** In that case, [sqlite3_value_nochange(X)] will return true for the 9350** same column in the [xUpdate] method. 9351** 9352** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 9353** implementations should continue to give a correct answer even if the 9354** sqlite3_vtab_nochange() interface were to always return false. In the 9355** current implementation, the sqlite3_vtab_nochange() interface does always 9356** returns false for the enhanced [UPDATE FROM] statement. 9357*/ 9358int sqlite3_vtab_nochange(sqlite3_context*); 9359 9360/* 9361** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9362** 9363** This function may only be called from within a call to the [xBestIndex] 9364** method of a [virtual table]. 9365** 9366** The first argument must be the sqlite3_index_info object that is the 9367** first parameter to the xBestIndex() method. The second argument must be 9368** an index into the aConstraint[] array belonging to the sqlite3_index_info 9369** structure passed to xBestIndex. This function returns a pointer to a buffer 9370** containing the name of the collation sequence for the corresponding 9371** constraint. 9372*/ 9373SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9374 9375/* 9376** CAPI3REF: Conflict resolution modes 9377** KEYWORDS: {conflict resolution mode} 9378** 9379** These constants are returned by [sqlite3_vtab_on_conflict()] to 9380** inform a [virtual table] implementation what the [ON CONFLICT] mode 9381** is for the SQL statement being evaluated. 9382** 9383** Note that the [SQLITE_IGNORE] constant is also used as a potential 9384** return value from the [sqlite3_set_authorizer()] callback and that 9385** [SQLITE_ABORT] is also a [result code]. 9386*/ 9387#define SQLITE_ROLLBACK 1 9388/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 9389#define SQLITE_FAIL 3 9390/* #define SQLITE_ABORT 4 // Also an error code */ 9391#define SQLITE_REPLACE 5 9392 9393/* 9394** CAPI3REF: Prepared Statement Scan Status Opcodes 9395** KEYWORDS: {scanstatus options} 9396** 9397** The following constants can be used for the T parameter to the 9398** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 9399** different metric for sqlite3_stmt_scanstatus() to return. 9400** 9401** When the value returned to V is a string, space to hold that string is 9402** managed by the prepared statement S and will be automatically freed when 9403** S is finalized. 9404** 9405** <dl> 9406** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 9407** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 9408** set to the total number of times that the X-th loop has run.</dd> 9409** 9410** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 9411** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 9412** to the total number of rows examined by all iterations of the X-th loop.</dd> 9413** 9414** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 9415** <dd>^The "double" variable pointed to by the V parameter will be set to the 9416** query planner's estimate for the average number of rows output from each 9417** iteration of the X-th loop. If the query planner's estimates was accurate, 9418** then this value will approximate the quotient NVISIT/NLOOP and the 9419** product of this value for all prior loops with the same SELECTID will 9420** be the NLOOP value for the current loop. 9421** 9422** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 9423** <dd>^The "const char *" variable pointed to by the V parameter will be set 9424** to a zero-terminated UTF-8 string containing the name of the index or table 9425** used for the X-th loop. 9426** 9427** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 9428** <dd>^The "const char *" variable pointed to by the V parameter will be set 9429** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 9430** description for the X-th loop. 9431** 9432** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 9433** <dd>^The "int" variable pointed to by the V parameter will be set to the 9434** "select-id" for the X-th loop. The select-id identifies which query or 9435** subquery the loop is part of. The main query has a select-id of zero. 9436** The select-id is the same value as is output in the first column 9437** of an [EXPLAIN QUERY PLAN] query. 9438** </dl> 9439*/ 9440#define SQLITE_SCANSTAT_NLOOP 0 9441#define SQLITE_SCANSTAT_NVISIT 1 9442#define SQLITE_SCANSTAT_EST 2 9443#define SQLITE_SCANSTAT_NAME 3 9444#define SQLITE_SCANSTAT_EXPLAIN 4 9445#define SQLITE_SCANSTAT_SELECTID 5 9446 9447/* 9448** CAPI3REF: Prepared Statement Scan Status 9449** METHOD: sqlite3_stmt 9450** 9451** This interface returns information about the predicted and measured 9452** performance for pStmt. Advanced applications can use this 9453** interface to compare the predicted and the measured performance and 9454** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 9455** 9456** Since this interface is expected to be rarely used, it is only 9457** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 9458** compile-time option. 9459** 9460** The "iScanStatusOp" parameter determines which status information to return. 9461** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 9462** of this interface is undefined. 9463** ^The requested measurement is written into a variable pointed to by 9464** the "pOut" parameter. 9465** Parameter "idx" identifies the specific loop to retrieve statistics for. 9466** Loops are numbered starting from zero. ^If idx is out of range - less than 9467** zero or greater than or equal to the total number of loops used to implement 9468** the statement - a non-zero value is returned and the variable that pOut 9469** points to is unchanged. 9470** 9471** ^Statistics might not be available for all loops in all statements. ^In cases 9472** where there exist loops with no available statistics, this function behaves 9473** as if the loop did not exist - it returns non-zero and leave the variable 9474** that pOut points to unchanged. 9475** 9476** See also: [sqlite3_stmt_scanstatus_reset()] 9477*/ 9478int sqlite3_stmt_scanstatus( 9479 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 9480 int idx, /* Index of loop to report on */ 9481 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 9482 void *pOut /* Result written here */ 9483); 9484 9485/* 9486** CAPI3REF: Zero Scan-Status Counters 9487** METHOD: sqlite3_stmt 9488** 9489** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 9490** 9491** This API is only available if the library is built with pre-processor 9492** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 9493*/ 9494void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 9495 9496/* 9497** CAPI3REF: Flush caches to disk mid-transaction 9498** METHOD: sqlite3 9499** 9500** ^If a write-transaction is open on [database connection] D when the 9501** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 9502** pages in the pager-cache that are not currently in use are written out 9503** to disk. A dirty page may be in use if a database cursor created by an 9504** active SQL statement is reading from it, or if it is page 1 of a database 9505** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 9506** interface flushes caches for all schemas - "main", "temp", and 9507** any [attached] databases. 9508** 9509** ^If this function needs to obtain extra database locks before dirty pages 9510** can be flushed to disk, it does so. ^If those locks cannot be obtained 9511** immediately and there is a busy-handler callback configured, it is invoked 9512** in the usual manner. ^If the required lock still cannot be obtained, then 9513** the database is skipped and an attempt made to flush any dirty pages 9514** belonging to the next (if any) database. ^If any databases are skipped 9515** because locks cannot be obtained, but no other error occurs, this 9516** function returns SQLITE_BUSY. 9517** 9518** ^If any other error occurs while flushing dirty pages to disk (for 9519** example an IO error or out-of-memory condition), then processing is 9520** abandoned and an SQLite [error code] is returned to the caller immediately. 9521** 9522** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 9523** 9524** ^This function does not set the database handle error code or message 9525** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 9526*/ 9527int sqlite3_db_cacheflush(sqlite3*); 9528 9529/* 9530** CAPI3REF: The pre-update hook. 9531** METHOD: sqlite3 9532** 9533** ^These interfaces are only available if SQLite is compiled using the 9534** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 9535** 9536** ^The [sqlite3_preupdate_hook()] interface registers a callback function 9537** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 9538** on a database table. 9539** ^At most one preupdate hook may be registered at a time on a single 9540** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 9541** the previous setting. 9542** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 9543** with a NULL pointer as the second parameter. 9544** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 9545** the first parameter to callbacks. 9546** 9547** ^The preupdate hook only fires for changes to real database tables; the 9548** preupdate hook is not invoked for changes to [virtual tables] or to 9549** system tables like sqlite_sequence or sqlite_stat1. 9550** 9551** ^The second parameter to the preupdate callback is a pointer to 9552** the [database connection] that registered the preupdate hook. 9553** ^The third parameter to the preupdate callback is one of the constants 9554** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 9555** kind of update operation that is about to occur. 9556** ^(The fourth parameter to the preupdate callback is the name of the 9557** database within the database connection that is being modified. This 9558** will be "main" for the main database or "temp" for TEMP tables or 9559** the name given after the AS keyword in the [ATTACH] statement for attached 9560** databases.)^ 9561** ^The fifth parameter to the preupdate callback is the name of the 9562** table that is being modified. 9563** 9564** For an UPDATE or DELETE operation on a [rowid table], the sixth 9565** parameter passed to the preupdate callback is the initial [rowid] of the 9566** row being modified or deleted. For an INSERT operation on a rowid table, 9567** or any operation on a WITHOUT ROWID table, the value of the sixth 9568** parameter is undefined. For an INSERT or UPDATE on a rowid table the 9569** seventh parameter is the final rowid value of the row being inserted 9570** or updated. The value of the seventh parameter passed to the callback 9571** function is not defined for operations on WITHOUT ROWID tables, or for 9572** DELETE operations on rowid tables. 9573** 9574** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 9575** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 9576** provide additional information about a preupdate event. These routines 9577** may only be called from within a preupdate callback. Invoking any of 9578** these routines from outside of a preupdate callback or with a 9579** [database connection] pointer that is different from the one supplied 9580** to the preupdate callback results in undefined and probably undesirable 9581** behavior. 9582** 9583** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 9584** in the row that is being inserted, updated, or deleted. 9585** 9586** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 9587** a [protected sqlite3_value] that contains the value of the Nth column of 9588** the table row before it is updated. The N parameter must be between 0 9589** and one less than the number of columns or the behavior will be 9590** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 9591** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 9592** behavior is undefined. The [sqlite3_value] that P points to 9593** will be destroyed when the preupdate callback returns. 9594** 9595** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 9596** a [protected sqlite3_value] that contains the value of the Nth column of 9597** the table row after it is updated. The N parameter must be between 0 9598** and one less than the number of columns or the behavior will be 9599** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 9600** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 9601** behavior is undefined. The [sqlite3_value] that P points to 9602** will be destroyed when the preupdate callback returns. 9603** 9604** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 9605** callback was invoked as a result of a direct insert, update, or delete 9606** operation; or 1 for inserts, updates, or deletes invoked by top-level 9607** triggers; or 2 for changes resulting from triggers called by top-level 9608** triggers; and so forth. 9609** 9610** When the [sqlite3_blob_write()] API is used to update a blob column, 9611** the pre-update hook is invoked with SQLITE_DELETE. This is because the 9612** in this case the new values are not available. In this case, when a 9613** callback made with op==SQLITE_DELETE is actuall a write using the 9614** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns 9615** the index of the column being written. In other cases, where the 9616** pre-update hook is being invoked for some other reason, including a 9617** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. 9618** 9619** See also: [sqlite3_update_hook()] 9620*/ 9621#if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 9622void *sqlite3_preupdate_hook( 9623 sqlite3 *db, 9624 void(*xPreUpdate)( 9625 void *pCtx, /* Copy of third arg to preupdate_hook() */ 9626 sqlite3 *db, /* Database handle */ 9627 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 9628 char const *zDb, /* Database name */ 9629 char const *zName, /* Table name */ 9630 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 9631 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 9632 ), 9633 void* 9634); 9635int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 9636int sqlite3_preupdate_count(sqlite3 *); 9637int sqlite3_preupdate_depth(sqlite3 *); 9638int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 9639int sqlite3_preupdate_blobwrite(sqlite3 *); 9640#endif 9641 9642/* 9643** CAPI3REF: Low-level system error code 9644** METHOD: sqlite3 9645** 9646** ^Attempt to return the underlying operating system error code or error 9647** number that caused the most recent I/O error or failure to open a file. 9648** The return value is OS-dependent. For example, on unix systems, after 9649** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 9650** called to get back the underlying "errno" that caused the problem, such 9651** as ENOSPC, EAUTH, EISDIR, and so forth. 9652*/ 9653int sqlite3_system_errno(sqlite3*); 9654 9655/* 9656** CAPI3REF: Database Snapshot 9657** KEYWORDS: {snapshot} {sqlite3_snapshot} 9658** 9659** An instance of the snapshot object records the state of a [WAL mode] 9660** database for some specific point in history. 9661** 9662** In [WAL mode], multiple [database connections] that are open on the 9663** same database file can each be reading a different historical version 9664** of the database file. When a [database connection] begins a read 9665** transaction, that connection sees an unchanging copy of the database 9666** as it existed for the point in time when the transaction first started. 9667** Subsequent changes to the database from other connections are not seen 9668** by the reader until a new read transaction is started. 9669** 9670** The sqlite3_snapshot object records state information about an historical 9671** version of the database file so that it is possible to later open a new read 9672** transaction that sees that historical version of the database rather than 9673** the most recent version. 9674*/ 9675typedef struct sqlite3_snapshot { 9676 unsigned char hidden[48]; 9677} sqlite3_snapshot; 9678 9679/* 9680** CAPI3REF: Record A Database Snapshot 9681** CONSTRUCTOR: sqlite3_snapshot 9682** 9683** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 9684** new [sqlite3_snapshot] object that records the current state of 9685** schema S in database connection D. ^On success, the 9686** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 9687** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 9688** If there is not already a read-transaction open on schema S when 9689** this function is called, one is opened automatically. 9690** 9691** The following must be true for this function to succeed. If any of 9692** the following statements are false when sqlite3_snapshot_get() is 9693** called, SQLITE_ERROR is returned. The final value of *P is undefined 9694** in this case. 9695** 9696** <ul> 9697** <li> The database handle must not be in [autocommit mode]. 9698** 9699** <li> Schema S of [database connection] D must be a [WAL mode] database. 9700** 9701** <li> There must not be a write transaction open on schema S of database 9702** connection D. 9703** 9704** <li> One or more transactions must have been written to the current wal 9705** file since it was created on disk (by any connection). This means 9706** that a snapshot cannot be taken on a wal mode database with no wal 9707** file immediately after it is first opened. At least one transaction 9708** must be written to it first. 9709** </ul> 9710** 9711** This function may also return SQLITE_NOMEM. If it is called with the 9712** database handle in autocommit mode but fails for some other reason, 9713** whether or not a read transaction is opened on schema S is undefined. 9714** 9715** The [sqlite3_snapshot] object returned from a successful call to 9716** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 9717** to avoid a memory leak. 9718** 9719** The [sqlite3_snapshot_get()] interface is only available when the 9720** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9721*/ 9722SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 9723 sqlite3 *db, 9724 const char *zSchema, 9725 sqlite3_snapshot **ppSnapshot 9726); 9727 9728/* 9729** CAPI3REF: Start a read transaction on an historical snapshot 9730** METHOD: sqlite3_snapshot 9731** 9732** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 9733** transaction or upgrades an existing one for schema S of 9734** [database connection] D such that the read transaction refers to 9735** historical [snapshot] P, rather than the most recent change to the 9736** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 9737** on success or an appropriate [error code] if it fails. 9738** 9739** ^In order to succeed, the database connection must not be in 9740** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 9741** is already a read transaction open on schema S, then the database handle 9742** must have no active statements (SELECT statements that have been passed 9743** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 9744** SQLITE_ERROR is returned if either of these conditions is violated, or 9745** if schema S does not exist, or if the snapshot object is invalid. 9746** 9747** ^A call to sqlite3_snapshot_open() will fail to open if the specified 9748** snapshot has been overwritten by a [checkpoint]. In this case 9749** SQLITE_ERROR_SNAPSHOT is returned. 9750** 9751** If there is already a read transaction open when this function is 9752** invoked, then the same read transaction remains open (on the same 9753** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 9754** is returned. If another error code - for example SQLITE_PROTOCOL or an 9755** SQLITE_IOERR error code - is returned, then the final state of the 9756** read transaction is undefined. If SQLITE_OK is returned, then the 9757** read transaction is now open on database snapshot P. 9758** 9759** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 9760** database connection D does not know that the database file for 9761** schema S is in [WAL mode]. A database connection might not know 9762** that the database file is in [WAL mode] if there has been no prior 9763** I/O on that database connection, or if the database entered [WAL mode] 9764** after the most recent I/O on the database connection.)^ 9765** (Hint: Run "[PRAGMA application_id]" against a newly opened 9766** database connection in order to make it ready to use snapshots.) 9767** 9768** The [sqlite3_snapshot_open()] interface is only available when the 9769** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9770*/ 9771SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 9772 sqlite3 *db, 9773 const char *zSchema, 9774 sqlite3_snapshot *pSnapshot 9775); 9776 9777/* 9778** CAPI3REF: Destroy a snapshot 9779** DESTRUCTOR: sqlite3_snapshot 9780** 9781** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 9782** The application must eventually free every [sqlite3_snapshot] object 9783** using this routine to avoid a memory leak. 9784** 9785** The [sqlite3_snapshot_free()] interface is only available when the 9786** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 9787*/ 9788SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 9789 9790/* 9791** CAPI3REF: Compare the ages of two snapshot handles. 9792** METHOD: sqlite3_snapshot 9793** 9794** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 9795** of two valid snapshot handles. 9796** 9797** If the two snapshot handles are not associated with the same database 9798** file, the result of the comparison is undefined. 9799** 9800** Additionally, the result of the comparison is only valid if both of the 9801** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 9802** last time the wal file was deleted. The wal file is deleted when the 9803** database is changed back to rollback mode or when the number of database 9804** clients drops to zero. If either snapshot handle was obtained before the 9805** wal file was last deleted, the value returned by this function 9806** is undefined. 9807** 9808** Otherwise, this API returns a negative value if P1 refers to an older 9809** snapshot than P2, zero if the two handles refer to the same database 9810** snapshot, and a positive value if P1 is a newer snapshot than P2. 9811** 9812** This interface is only available if SQLite is compiled with the 9813** [SQLITE_ENABLE_SNAPSHOT] option. 9814*/ 9815SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 9816 sqlite3_snapshot *p1, 9817 sqlite3_snapshot *p2 9818); 9819 9820/* 9821** CAPI3REF: Recover snapshots from a wal file 9822** METHOD: sqlite3_snapshot 9823** 9824** If a [WAL file] remains on disk after all database connections close 9825** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 9826** or because the last process to have the database opened exited without 9827** calling [sqlite3_close()]) and a new connection is subsequently opened 9828** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 9829** will only be able to open the last transaction added to the WAL file 9830** even though the WAL file contains other valid transactions. 9831** 9832** This function attempts to scan the WAL file associated with database zDb 9833** of database handle db and make all valid snapshots available to 9834** sqlite3_snapshot_open(). It is an error if there is already a read 9835** transaction open on the database, or if the database is not a WAL mode 9836** database. 9837** 9838** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 9839** 9840** This interface is only available if SQLite is compiled with the 9841** [SQLITE_ENABLE_SNAPSHOT] option. 9842*/ 9843SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 9844 9845/* 9846** CAPI3REF: Serialize a database 9847** 9848** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 9849** that is a serialization of the S database on [database connection] D. 9850** If P is not a NULL pointer, then the size of the database in bytes 9851** is written into *P. 9852** 9853** For an ordinary on-disk database file, the serialization is just a 9854** copy of the disk file. For an in-memory database or a "TEMP" database, 9855** the serialization is the same sequence of bytes which would be written 9856** to disk if that database where backed up to disk. 9857** 9858** The usual case is that sqlite3_serialize() copies the serialization of 9859** the database into memory obtained from [sqlite3_malloc64()] and returns 9860** a pointer to that memory. The caller is responsible for freeing the 9861** returned value to avoid a memory leak. However, if the F argument 9862** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 9863** are made, and the sqlite3_serialize() function will return a pointer 9864** to the contiguous memory representation of the database that SQLite 9865** is currently using for that database, or NULL if the no such contiguous 9866** memory representation of the database exists. A contiguous memory 9867** representation of the database will usually only exist if there has 9868** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 9869** values of D and S. 9870** The size of the database is written into *P even if the 9871** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 9872** of the database exists. 9873** 9874** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 9875** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 9876** allocation error occurs. 9877** 9878** This interface is omitted if SQLite is compiled with the 9879** [SQLITE_OMIT_DESERIALIZE] option. 9880*/ 9881unsigned char *sqlite3_serialize( 9882 sqlite3 *db, /* The database connection */ 9883 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 9884 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 9885 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 9886); 9887 9888/* 9889** CAPI3REF: Flags for sqlite3_serialize 9890** 9891** Zero or more of the following constants can be OR-ed together for 9892** the F argument to [sqlite3_serialize(D,S,P,F)]. 9893** 9894** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 9895** a pointer to contiguous in-memory database that it is currently using, 9896** without making a copy of the database. If SQLite is not currently using 9897** a contiguous in-memory database, then this option causes 9898** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 9899** using a contiguous in-memory database if it has been initialized by a 9900** prior call to [sqlite3_deserialize()]. 9901*/ 9902#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 9903 9904/* 9905** CAPI3REF: Deserialize a database 9906** 9907** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 9908** [database connection] D to disconnect from database S and then 9909** reopen S as an in-memory database based on the serialization contained 9910** in P. The serialized database P is N bytes in size. M is the size of 9911** the buffer P, which might be larger than N. If M is larger than N, and 9912** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 9913** permitted to add content to the in-memory database as long as the total 9914** size does not exceed M bytes. 9915** 9916** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 9917** invoke sqlite3_free() on the serialization buffer when the database 9918** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 9919** SQLite will try to increase the buffer size using sqlite3_realloc64() 9920** if writes on the database cause it to grow larger than M bytes. 9921** 9922** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 9923** database is currently in a read transaction or is involved in a backup 9924** operation. 9925** 9926** It is not possible to deserialized into the TEMP database. If the 9927** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the 9928** function returns SQLITE_ERROR. 9929** 9930** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 9931** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 9932** [sqlite3_free()] is invoked on argument P prior to returning. 9933** 9934** This interface is omitted if SQLite is compiled with the 9935** [SQLITE_OMIT_DESERIALIZE] option. 9936*/ 9937int sqlite3_deserialize( 9938 sqlite3 *db, /* The database connection */ 9939 const char *zSchema, /* Which DB to reopen with the deserialization */ 9940 unsigned char *pData, /* The serialized database content */ 9941 sqlite3_int64 szDb, /* Number bytes in the deserialization */ 9942 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 9943 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 9944); 9945 9946/* 9947** CAPI3REF: Flags for sqlite3_deserialize() 9948** 9949** The following are allowed values for 6th argument (the F argument) to 9950** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 9951** 9952** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 9953** in the P argument is held in memory obtained from [sqlite3_malloc64()] 9954** and that SQLite should take ownership of this memory and automatically 9955** free it when it has finished using it. Without this flag, the caller 9956** is responsible for freeing any dynamically allocated memory. 9957** 9958** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 9959** grow the size of the database using calls to [sqlite3_realloc64()]. This 9960** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 9961** Without this flag, the deserialized database cannot increase in size beyond 9962** the number of bytes specified by the M parameter. 9963** 9964** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 9965** should be treated as read-only. 9966*/ 9967#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 9968#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 9969#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 9970 9971/* 9972** Undo the hack that converts floating point types to integer for 9973** builds on processors without floating point support. 9974*/ 9975#ifdef SQLITE_OMIT_FLOATING_POINT 9976# undef double 9977#endif 9978 9979#ifdef __cplusplus 9980} /* End of the 'extern "C"' block */ 9981#endif 9982#endif /* SQLITE3_H */ 9983