1/* 2** 2001-09-15 3** 4** The author disclaims copyright to this source code. In place of 5** a legal notice, here is a blessing: 6** 7** May you do good and not evil. 8** May you find forgiveness for yourself and forgive others. 9** May you share freely, never taking more than you give. 10** 11************************************************************************* 12** This header file defines the interface that the SQLite library 13** presents to client programs. If a C-function, structure, datatype, 14** or constant definition does not appear in this file, then it is 15** not a published API of SQLite, is subject to change without 16** notice, and should not be referenced by programs that use SQLite. 17** 18** Some of the definitions that are in this file are marked as 19** "experimental". Experimental interfaces are normally new 20** features recently added to SQLite. We do not anticipate changes 21** to experimental interfaces but reserve the right to make minor changes 22** if experience from use "in the wild" suggest such changes are prudent. 23** 24** The official C-language API documentation for SQLite is derived 25** from comments in this file. This file is the authoritative source 26** on how SQLite interfaces are supposed to operate. 27** 28** The name of this file under configuration management is "sqlite.h.in". 29** The makefile makes some minor changes to this file (such as inserting 30** the version number) and changes its name to "sqlite3.h" as 31** part of the build process. 32*/ 33#ifndef SQLITE3_H 34#define SQLITE3_H 35#include <stdarg.h> /* Needed for the definition of va_list */ 36 37/* 38** Make sure we can call this stuff from C++. 39*/ 40#ifdef __cplusplus 41extern "C" { 42#endif 43 44 45/* 46** Facilitate override of interface linkage and calling conventions. 47** Be aware that these macros may not be used within this particular 48** translation of the amalgamation and its associated header file. 49** 50** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the 51** compiler that the target identifier should have external linkage. 52** 53** The SQLITE_CDECL macro is used to set the calling convention for 54** public functions that accept a variable number of arguments. 55** 56** The SQLITE_APICALL macro is used to set the calling convention for 57** public functions that accept a fixed number of arguments. 58** 59** The SQLITE_STDCALL macro is no longer used and is now deprecated. 60** 61** The SQLITE_CALLBACK macro is used to set the calling convention for 62** function pointers. 63** 64** The SQLITE_SYSAPI macro is used to set the calling convention for 65** functions provided by the operating system. 66** 67** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and 68** SQLITE_SYSAPI macros are used only when building for environments 69** that require non-default calling conventions. 70*/ 71#ifndef SQLITE_EXTERN 72# define SQLITE_EXTERN extern 73#endif 74#ifndef SQLITE_API 75# define SQLITE_API 76#endif 77#ifndef SQLITE_CDECL 78# define SQLITE_CDECL 79#endif 80#ifndef SQLITE_APICALL 81# define SQLITE_APICALL 82#endif 83#ifndef SQLITE_STDCALL 84# define SQLITE_STDCALL SQLITE_APICALL 85#endif 86#ifndef SQLITE_CALLBACK 87# define SQLITE_CALLBACK 88#endif 89#ifndef SQLITE_SYSAPI 90# define SQLITE_SYSAPI 91#endif 92 93/* 94** These no-op macros are used in front of interfaces to mark those 95** interfaces as either deprecated or experimental. New applications 96** should not use deprecated interfaces - they are supported for backwards 97** compatibility only. Application writers should be aware that 98** experimental interfaces are subject to change in point releases. 99** 100** These macros used to resolve to various kinds of compiler magic that 101** would generate warning messages when they were used. But that 102** compiler magic ended up generating such a flurry of bug reports 103** that we have taken it all out and gone back to using simple 104** noop macros. 105*/ 106#define SQLITE_DEPRECATED 107#define SQLITE_EXPERIMENTAL 108 109/* 110** Ensure these symbols were not defined by some previous header file. 111*/ 112#ifdef SQLITE_VERSION 113# undef SQLITE_VERSION 114#endif 115#ifdef SQLITE_VERSION_NUMBER 116# undef SQLITE_VERSION_NUMBER 117#endif 118 119/* 120** CAPI3REF: Compile-Time Library Version Numbers 121** 122** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 123** evaluates to a string literal that is the SQLite version in the 124** format "X.Y.Z" where X is the major version number (always 3 for 125** SQLite3) and Y is the minor version number and Z is the release number.)^ 126** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 127** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 128** numbers used in [SQLITE_VERSION].)^ 129** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 130** be larger than the release from which it is derived. Either Y will 131** be held constant and Z will be incremented or else Y will be incremented 132** and Z will be reset to zero. 133** 134** Since [version 3.6.18] ([dateof:3.6.18]), 135** SQLite source code has been stored in the 136** <a href="http://www.fossil-scm.org/">Fossil configuration management 137** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 138** a string which identifies a particular check-in of SQLite 139** within its configuration management system. ^The SQLITE_SOURCE_ID 140** string contains the date and time of the check-in (UTC) and a SHA1 141** or SHA3-256 hash of the entire source tree. If the source code has 142** been edited in any way since it was last checked in, then the last 143** four hexadecimal digits of the hash may be modified. 144** 145** See also: [sqlite3_libversion()], 146** [sqlite3_libversion_number()], [sqlite3_sourceid()], 147** [sqlite_version()] and [sqlite_source_id()]. 148*/ 149#define SQLITE_VERSION "--VERS--" 150#define SQLITE_VERSION_NUMBER --VERSION-NUMBER-- 151#define SQLITE_SOURCE_ID "--SOURCE-ID--" 152 153/* 154** CAPI3REF: Run-Time Library Version Numbers 155** KEYWORDS: sqlite3_version sqlite3_sourceid 156** 157** These interfaces provide the same information as the [SQLITE_VERSION], 158** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 159** but are associated with the library instead of the header file. ^(Cautious 160** programmers might include assert() statements in their application to 161** verify that values returned by these interfaces match the macros in 162** the header, and thus ensure that the application is 163** compiled with matching library and header files. 164** 165** <blockquote><pre> 166** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 167** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 168** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 169** </pre></blockquote>)^ 170** 171** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 172** macro. ^The sqlite3_libversion() function returns a pointer to the 173** to the sqlite3_version[] string constant. The sqlite3_libversion() 174** function is provided for use in DLLs since DLL users usually do not have 175** direct access to string constants within the DLL. ^The 176** sqlite3_libversion_number() function returns an integer equal to 177** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 178** a pointer to a string constant whose value is the same as the 179** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 180** using an edited copy of [the amalgamation], then the last four characters 181** of the hash might be different from [SQLITE_SOURCE_ID].)^ 182** 183** See also: [sqlite_version()] and [sqlite_source_id()]. 184*/ 185SQLITE_EXTERN const char sqlite3_version[]; 186const char *sqlite3_libversion(void); 187const char *sqlite3_sourceid(void); 188int sqlite3_libversion_number(void); 189 190/* 191** CAPI3REF: Run-Time Library Compilation Options Diagnostics 192** 193** ^The sqlite3_compileoption_used() function returns 0 or 1 194** indicating whether the specified option was defined at 195** compile time. ^The SQLITE_ prefix may be omitted from the 196** option name passed to sqlite3_compileoption_used(). 197** 198** ^The sqlite3_compileoption_get() function allows iterating 199** over the list of options that were defined at compile time by 200** returning the N-th compile time option string. ^If N is out of range, 201** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 202** prefix is omitted from any strings returned by 203** sqlite3_compileoption_get(). 204** 205** ^Support for the diagnostic functions sqlite3_compileoption_used() 206** and sqlite3_compileoption_get() may be omitted by specifying the 207** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 208** 209** See also: SQL functions [sqlite_compileoption_used()] and 210** [sqlite_compileoption_get()] and the [compile_options pragma]. 211*/ 212#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 213int sqlite3_compileoption_used(const char *zOptName); 214const char *sqlite3_compileoption_get(int N); 215#else 216# define sqlite3_compileoption_used(X) 0 217# define sqlite3_compileoption_get(X) ((void*)0) 218#endif 219 220/* 221** CAPI3REF: Test To See If The Library Is Threadsafe 222** 223** ^The sqlite3_threadsafe() function returns zero if and only if 224** SQLite was compiled with mutexing code omitted due to the 225** [SQLITE_THREADSAFE] compile-time option being set to 0. 226** 227** SQLite can be compiled with or without mutexes. When 228** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 229** are enabled and SQLite is threadsafe. When the 230** [SQLITE_THREADSAFE] macro is 0, 231** the mutexes are omitted. Without the mutexes, it is not safe 232** to use SQLite concurrently from more than one thread. 233** 234** Enabling mutexes incurs a measurable performance penalty. 235** So if speed is of utmost importance, it makes sense to disable 236** the mutexes. But for maximum safety, mutexes should be enabled. 237** ^The default behavior is for mutexes to be enabled. 238** 239** This interface can be used by an application to make sure that the 240** version of SQLite that it is linking against was compiled with 241** the desired setting of the [SQLITE_THREADSAFE] macro. 242** 243** This interface only reports on the compile-time mutex setting 244** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 245** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 246** can be fully or partially disabled using a call to [sqlite3_config()] 247** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 248** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 249** sqlite3_threadsafe() function shows only the compile-time setting of 250** thread safety, not any run-time changes to that setting made by 251** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 252** is unchanged by calls to sqlite3_config().)^ 253** 254** See the [threading mode] documentation for additional information. 255*/ 256int sqlite3_threadsafe(void); 257 258/* 259** CAPI3REF: Database Connection Handle 260** KEYWORDS: {database connection} {database connections} 261** 262** Each open SQLite database is represented by a pointer to an instance of 263** the opaque structure named "sqlite3". It is useful to think of an sqlite3 264** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 265** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 266** and [sqlite3_close_v2()] are its destructors. There are many other 267** interfaces (such as 268** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 269** [sqlite3_busy_timeout()] to name but three) that are methods on an 270** sqlite3 object. 271*/ 272typedef struct sqlite3 sqlite3; 273 274/* 275** CAPI3REF: 64-Bit Integer Types 276** KEYWORDS: sqlite_int64 sqlite_uint64 277** 278** Because there is no cross-platform way to specify 64-bit integer types 279** SQLite includes typedefs for 64-bit signed and unsigned integers. 280** 281** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 282** The sqlite_int64 and sqlite_uint64 types are supported for backwards 283** compatibility only. 284** 285** ^The sqlite3_int64 and sqlite_int64 types can store integer values 286** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 287** sqlite3_uint64 and sqlite_uint64 types can store integer values 288** between 0 and +18446744073709551615 inclusive. 289*/ 290#ifdef SQLITE_INT64_TYPE 291 typedef SQLITE_INT64_TYPE sqlite_int64; 292# ifdef SQLITE_UINT64_TYPE 293 typedef SQLITE_UINT64_TYPE sqlite_uint64; 294# else 295 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 296# endif 297#elif defined(_MSC_VER) || defined(__BORLANDC__) 298 typedef __int64 sqlite_int64; 299 typedef unsigned __int64 sqlite_uint64; 300#else 301 typedef long long int sqlite_int64; 302 typedef unsigned long long int sqlite_uint64; 303#endif 304typedef sqlite_int64 sqlite3_int64; 305typedef sqlite_uint64 sqlite3_uint64; 306 307/* 308** If compiling for a processor that lacks floating point support, 309** substitute integer for floating-point. 310*/ 311#ifdef SQLITE_OMIT_FLOATING_POINT 312# define double sqlite3_int64 313#endif 314 315/* 316** CAPI3REF: Closing A Database Connection 317** DESTRUCTOR: sqlite3 318** 319** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 320** for the [sqlite3] object. 321** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 322** the [sqlite3] object is successfully destroyed and all associated 323** resources are deallocated. 324** 325** Ideally, applications should [sqlite3_finalize | finalize] all 326** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 327** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 328** with the [sqlite3] object prior to attempting to close the object. 329** ^If the database connection is associated with unfinalized prepared 330** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then 331** sqlite3_close() will leave the database connection open and return 332** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared 333** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, 334** it returns [SQLITE_OK] regardless, but instead of deallocating the database 335** connection immediately, it marks the database connection as an unusable 336** "zombie" and makes arrangements to automatically deallocate the database 337** connection after all prepared statements are finalized, all BLOB handles 338** are closed, and all backups have finished. The sqlite3_close_v2() interface 339** is intended for use with host languages that are garbage collected, and 340** where the order in which destructors are called is arbitrary. 341** 342** ^If an [sqlite3] object is destroyed while a transaction is open, 343** the transaction is automatically rolled back. 344** 345** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 346** must be either a NULL 347** pointer or an [sqlite3] object pointer obtained 348** from [sqlite3_open()], [sqlite3_open16()], or 349** [sqlite3_open_v2()], and not previously closed. 350** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 351** argument is a harmless no-op. 352*/ 353int sqlite3_close(sqlite3*); 354int sqlite3_close_v2(sqlite3*); 355 356/* 357** The type for a callback function. 358** This is legacy and deprecated. It is included for historical 359** compatibility and is not documented. 360*/ 361typedef int (*sqlite3_callback)(void*,int,char**, char**); 362 363/* 364** CAPI3REF: One-Step Query Execution Interface 365** METHOD: sqlite3 366** 367** The sqlite3_exec() interface is a convenience wrapper around 368** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 369** that allows an application to run multiple statements of SQL 370** without having to use a lot of C code. 371** 372** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 373** semicolon-separate SQL statements passed into its 2nd argument, 374** in the context of the [database connection] passed in as its 1st 375** argument. ^If the callback function of the 3rd argument to 376** sqlite3_exec() is not NULL, then it is invoked for each result row 377** coming out of the evaluated SQL statements. ^The 4th argument to 378** sqlite3_exec() is relayed through to the 1st argument of each 379** callback invocation. ^If the callback pointer to sqlite3_exec() 380** is NULL, then no callback is ever invoked and result rows are 381** ignored. 382** 383** ^If an error occurs while evaluating the SQL statements passed into 384** sqlite3_exec(), then execution of the current statement stops and 385** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 386** is not NULL then any error message is written into memory obtained 387** from [sqlite3_malloc()] and passed back through the 5th parameter. 388** To avoid memory leaks, the application should invoke [sqlite3_free()] 389** on error message strings returned through the 5th parameter of 390** sqlite3_exec() after the error message string is no longer needed. 391** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 392** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 393** NULL before returning. 394** 395** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 396** routine returns SQLITE_ABORT without invoking the callback again and 397** without running any subsequent SQL statements. 398** 399** ^The 2nd argument to the sqlite3_exec() callback function is the 400** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 401** callback is an array of pointers to strings obtained as if from 402** [sqlite3_column_text()], one for each column. ^If an element of a 403** result row is NULL then the corresponding string pointer for the 404** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 405** sqlite3_exec() callback is an array of pointers to strings where each 406** entry represents the name of corresponding result column as obtained 407** from [sqlite3_column_name()]. 408** 409** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 410** to an empty string, or a pointer that contains only whitespace and/or 411** SQL comments, then no SQL statements are evaluated and the database 412** is not changed. 413** 414** Restrictions: 415** 416** <ul> 417** <li> The application must ensure that the 1st parameter to sqlite3_exec() 418** is a valid and open [database connection]. 419** <li> The application must not close the [database connection] specified by 420** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 421** <li> The application must not modify the SQL statement text passed into 422** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 423** </ul> 424*/ 425int sqlite3_exec( 426 sqlite3*, /* An open database */ 427 const char *sql, /* SQL to be evaluated */ 428 int (*callback)(void*,int,char**,char**), /* Callback function */ 429 void *, /* 1st argument to callback */ 430 char **errmsg /* Error msg written here */ 431); 432 433/* 434** CAPI3REF: Result Codes 435** KEYWORDS: {result code definitions} 436** 437** Many SQLite functions return an integer result code from the set shown 438** here in order to indicate success or failure. 439** 440** New error codes may be added in future versions of SQLite. 441** 442** See also: [extended result code definitions] 443*/ 444#define SQLITE_OK 0 /* Successful result */ 445/* beginning-of-error-codes */ 446#define SQLITE_ERROR 1 /* Generic error */ 447#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 448#define SQLITE_PERM 3 /* Access permission denied */ 449#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 450#define SQLITE_BUSY 5 /* The database file is locked */ 451#define SQLITE_LOCKED 6 /* A table in the database is locked */ 452#define SQLITE_NOMEM 7 /* A malloc() failed */ 453#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 454#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 455#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 456#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 457#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 458#define SQLITE_FULL 13 /* Insertion failed because database is full */ 459#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 460#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 461#define SQLITE_EMPTY 16 /* Internal use only */ 462#define SQLITE_SCHEMA 17 /* The database schema changed */ 463#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 464#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 465#define SQLITE_MISMATCH 20 /* Data type mismatch */ 466#define SQLITE_MISUSE 21 /* Library used incorrectly */ 467#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 468#define SQLITE_AUTH 23 /* Authorization denied */ 469#define SQLITE_FORMAT 24 /* Not used */ 470#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 471#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 472#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 473#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 474#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 475#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 476/* end-of-error-codes */ 477 478/* 479** CAPI3REF: Extended Result Codes 480** KEYWORDS: {extended result code definitions} 481** 482** In its default configuration, SQLite API routines return one of 30 integer 483** [result codes]. However, experience has shown that many of 484** these result codes are too coarse-grained. They do not provide as 485** much information about problems as programmers might like. In an effort to 486** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 487** and later) include 488** support for additional result codes that provide more detailed information 489** about errors. These [extended result codes] are enabled or disabled 490** on a per database connection basis using the 491** [sqlite3_extended_result_codes()] API. Or, the extended code for 492** the most recent error can be obtained using 493** [sqlite3_extended_errcode()]. 494*/ 495#define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 496#define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 497#define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 498#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 499#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 500#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 501#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 502#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 503#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 504#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 505#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 506#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 507#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 508#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 509#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 510#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 511#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 512#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 513#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 514#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 515#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 516#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 517#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 518#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 519#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 520#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 521#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 522#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 523#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 524#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 525#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 526#define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 527#define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 528#define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 529#define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) 530#define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) 531#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 532#define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 533#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 534#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 535#define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) 536#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 537#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 538#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 539#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 540#define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 541#define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 542#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 543#define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 544#define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 545#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 546#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 547#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 548#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 549#define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 550#define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 551#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 552#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 553#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 554#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 555#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 556#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 557#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 558#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 559#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 560#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 561#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 562#define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 563#define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) 564#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 565#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 566#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 567#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 568#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 569#define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */ 570 571/* 572** CAPI3REF: Flags For File Open Operations 573** 574** These bit values are intended for use in the 575** 3rd parameter to the [sqlite3_open_v2()] interface and 576** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 577** 578** Only those flags marked as "Ok for sqlite3_open_v2()" may be 579** used as the third argument to the [sqlite3_open_v2()] interface. 580** The other flags have historically been ignored by sqlite3_open_v2(), 581** though future versions of SQLite might change so that an error is 582** raised if any of the disallowed bits are passed into sqlite3_open_v2(). 583** Applications should not depend on the historical behavior. 584** 585** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into 586** [sqlite3_open_v2()] does *not* cause the underlying database file 587** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into 588** [sqlite3_open_v2()] has historically be a no-op and might become an 589** error in future versions of SQLite. 590*/ 591#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 592#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 593#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 594#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 595#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 596#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 597#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 598#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 599#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 600#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 601#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 602#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 603#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 604#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 605#define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 606#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 607#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 608#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 609#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 610#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 611#define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 612#define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ 613 614/* Reserved: 0x00F00000 */ 615/* Legacy compatibility: */ 616#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 617 618 619/* 620** CAPI3REF: Device Characteristics 621** 622** The xDeviceCharacteristics method of the [sqlite3_io_methods] 623** object returns an integer which is a vector of these 624** bit values expressing I/O characteristics of the mass storage 625** device that holds the file that the [sqlite3_io_methods] 626** refers to. 627** 628** The SQLITE_IOCAP_ATOMIC property means that all writes of 629** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 630** mean that writes of blocks that are nnn bytes in size and 631** are aligned to an address which is an integer multiple of 632** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 633** that when data is appended to a file, the data is appended 634** first then the size of the file is extended, never the other 635** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 636** information is written to disk in the same order as calls 637** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 638** after reboot following a crash or power loss, the only bytes in a 639** file that were written at the application level might have changed 640** and that adjacent bytes, even bytes within the same sector are 641** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 642** flag indicates that a file cannot be deleted when open. The 643** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 644** read-only media and cannot be changed even by processes with 645** elevated privileges. 646** 647** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 648** filesystem supports doing multiple write operations atomically when those 649** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 650** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 651*/ 652#define SQLITE_IOCAP_ATOMIC 0x00000001 653#define SQLITE_IOCAP_ATOMIC512 0x00000002 654#define SQLITE_IOCAP_ATOMIC1K 0x00000004 655#define SQLITE_IOCAP_ATOMIC2K 0x00000008 656#define SQLITE_IOCAP_ATOMIC4K 0x00000010 657#define SQLITE_IOCAP_ATOMIC8K 0x00000020 658#define SQLITE_IOCAP_ATOMIC16K 0x00000040 659#define SQLITE_IOCAP_ATOMIC32K 0x00000080 660#define SQLITE_IOCAP_ATOMIC64K 0x00000100 661#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 662#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 663#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 664#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 665#define SQLITE_IOCAP_IMMUTABLE 0x00002000 666#define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 667 668/* 669** CAPI3REF: File Locking Levels 670** 671** SQLite uses one of these integer values as the second 672** argument to calls it makes to the xLock() and xUnlock() methods 673** of an [sqlite3_io_methods] object. These values are ordered from 674** lest restrictive to most restrictive. 675** 676** The argument to xLock() is always SHARED or higher. The argument to 677** xUnlock is either SHARED or NONE. 678*/ 679#define SQLITE_LOCK_NONE 0 /* xUnlock() only */ 680#define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ 681#define SQLITE_LOCK_RESERVED 2 /* xLock() only */ 682#define SQLITE_LOCK_PENDING 3 /* xLock() only */ 683#define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ 684 685/* 686** CAPI3REF: Synchronization Type Flags 687** 688** When SQLite invokes the xSync() method of an 689** [sqlite3_io_methods] object it uses a combination of 690** these integer values as the second argument. 691** 692** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 693** sync operation only needs to flush data to mass storage. Inode 694** information need not be flushed. If the lower four bits of the flag 695** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 696** If the lower four bits equal SQLITE_SYNC_FULL, that means 697** to use Mac OS X style fullsync instead of fsync(). 698** 699** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 700** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 701** settings. The [synchronous pragma] determines when calls to the 702** xSync VFS method occur and applies uniformly across all platforms. 703** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 704** energetic or rigorous or forceful the sync operations are and 705** only make a difference on Mac OSX for the default SQLite code. 706** (Third-party VFS implementations might also make the distinction 707** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 708** operating systems natively supported by SQLite, only Mac OSX 709** cares about the difference.) 710*/ 711#define SQLITE_SYNC_NORMAL 0x00002 712#define SQLITE_SYNC_FULL 0x00003 713#define SQLITE_SYNC_DATAONLY 0x00010 714 715/* 716** CAPI3REF: OS Interface Open File Handle 717** 718** An [sqlite3_file] object represents an open file in the 719** [sqlite3_vfs | OS interface layer]. Individual OS interface 720** implementations will 721** want to subclass this object by appending additional fields 722** for their own use. The pMethods entry is a pointer to an 723** [sqlite3_io_methods] object that defines methods for performing 724** I/O operations on the open file. 725*/ 726typedef struct sqlite3_file sqlite3_file; 727struct sqlite3_file { 728 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 729}; 730 731/* 732** CAPI3REF: OS Interface File Virtual Methods Object 733** 734** Every file opened by the [sqlite3_vfs.xOpen] method populates an 735** [sqlite3_file] object (or, more commonly, a subclass of the 736** [sqlite3_file] object) with a pointer to an instance of this object. 737** This object defines the methods used to perform various operations 738** against the open file represented by the [sqlite3_file] object. 739** 740** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 741** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 742** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 743** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 744** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 745** to NULL. 746** 747** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 748** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 749** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 750** flag may be ORed in to indicate that only the data of the file 751** and not its inode needs to be synced. 752** 753** The integer values to xLock() and xUnlock() are one of 754** <ul> 755** <li> [SQLITE_LOCK_NONE], 756** <li> [SQLITE_LOCK_SHARED], 757** <li> [SQLITE_LOCK_RESERVED], 758** <li> [SQLITE_LOCK_PENDING], or 759** <li> [SQLITE_LOCK_EXCLUSIVE]. 760** </ul> 761** xLock() upgrades the database file lock. In other words, xLock() moves the 762** database file lock in the direction NONE toward EXCLUSIVE. The argument to 763** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never 764** SQLITE_LOCK_NONE. If the database file lock is already at or above the 765** requested lock, then the call to xLock() is a no-op. 766** xUnlock() downgrades the database file lock to either SHARED or NONE. 767* If the lock is already at or below the requested lock state, then the call 768** to xUnlock() is a no-op. 769** The xCheckReservedLock() method checks whether any database connection, 770** either in this process or in some other process, is holding a RESERVED, 771** PENDING, or EXCLUSIVE lock on the file. It returns true 772** if such a lock exists and false otherwise. 773** 774** The xFileControl() method is a generic interface that allows custom 775** VFS implementations to directly control an open file using the 776** [sqlite3_file_control()] interface. The second "op" argument is an 777** integer opcode. The third argument is a generic pointer intended to 778** point to a structure that may contain arguments or space in which to 779** write return values. Potential uses for xFileControl() might be 780** functions to enable blocking locks with timeouts, to change the 781** locking strategy (for example to use dot-file locks), to inquire 782** about the status of a lock, or to break stale locks. The SQLite 783** core reserves all opcodes less than 100 for its own use. 784** A [file control opcodes | list of opcodes] less than 100 is available. 785** Applications that define a custom xFileControl method should use opcodes 786** greater than 100 to avoid conflicts. VFS implementations should 787** return [SQLITE_NOTFOUND] for file control opcodes that they do not 788** recognize. 789** 790** The xSectorSize() method returns the sector size of the 791** device that underlies the file. The sector size is the 792** minimum write that can be performed without disturbing 793** other bytes in the file. The xDeviceCharacteristics() 794** method returns a bit vector describing behaviors of the 795** underlying device: 796** 797** <ul> 798** <li> [SQLITE_IOCAP_ATOMIC] 799** <li> [SQLITE_IOCAP_ATOMIC512] 800** <li> [SQLITE_IOCAP_ATOMIC1K] 801** <li> [SQLITE_IOCAP_ATOMIC2K] 802** <li> [SQLITE_IOCAP_ATOMIC4K] 803** <li> [SQLITE_IOCAP_ATOMIC8K] 804** <li> [SQLITE_IOCAP_ATOMIC16K] 805** <li> [SQLITE_IOCAP_ATOMIC32K] 806** <li> [SQLITE_IOCAP_ATOMIC64K] 807** <li> [SQLITE_IOCAP_SAFE_APPEND] 808** <li> [SQLITE_IOCAP_SEQUENTIAL] 809** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 810** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 811** <li> [SQLITE_IOCAP_IMMUTABLE] 812** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 813** </ul> 814** 815** The SQLITE_IOCAP_ATOMIC property means that all writes of 816** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 817** mean that writes of blocks that are nnn bytes in size and 818** are aligned to an address which is an integer multiple of 819** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 820** that when data is appended to a file, the data is appended 821** first then the size of the file is extended, never the other 822** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 823** information is written to disk in the same order as calls 824** to xWrite(). 825** 826** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 827** in the unread portions of the buffer with zeros. A VFS that 828** fails to zero-fill short reads might seem to work. However, 829** failure to zero-fill short reads will eventually lead to 830** database corruption. 831*/ 832typedef struct sqlite3_io_methods sqlite3_io_methods; 833struct sqlite3_io_methods { 834 int iVersion; 835 int (*xClose)(sqlite3_file*); 836 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 837 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 838 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 839 int (*xSync)(sqlite3_file*, int flags); 840 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 841 int (*xLock)(sqlite3_file*, int); 842 int (*xUnlock)(sqlite3_file*, int); 843 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 844 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 845 int (*xSectorSize)(sqlite3_file*); 846 int (*xDeviceCharacteristics)(sqlite3_file*); 847 /* Methods above are valid for version 1 */ 848 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 849 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 850 void (*xShmBarrier)(sqlite3_file*); 851 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 852 /* Methods above are valid for version 2 */ 853 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 854 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 855 /* Methods above are valid for version 3 */ 856 /* Additional methods may be added in future releases */ 857}; 858 859/* 860** CAPI3REF: Standard File Control Opcodes 861** KEYWORDS: {file control opcodes} {file control opcode} 862** 863** These integer constants are opcodes for the xFileControl method 864** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 865** interface. 866** 867** <ul> 868** <li>[[SQLITE_FCNTL_LOCKSTATE]] 869** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 870** opcode causes the xFileControl method to write the current state of 871** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 872** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 873** into an integer that the pArg argument points to. 874** This capability is only available if SQLite is compiled with [SQLITE_DEBUG]. 875** 876** <li>[[SQLITE_FCNTL_SIZE_HINT]] 877** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 878** layer a hint of how large the database file will grow to be during the 879** current transaction. This hint is not guaranteed to be accurate but it 880** is often close. The underlying VFS might choose to preallocate database 881** file space based on this hint in order to help writes to the database 882** file run faster. 883** 884** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 885** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 886** implements [sqlite3_deserialize()] to set an upper bound on the size 887** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 888** If the integer pointed to is negative, then it is filled in with the 889** current limit. Otherwise the limit is set to the larger of the value 890** of the integer pointed to and the current database size. The integer 891** pointed to is set to the new limit. 892** 893** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 894** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 895** extends and truncates the database file in chunks of a size specified 896** by the user. The fourth argument to [sqlite3_file_control()] should 897** point to an integer (type int) containing the new chunk-size to use 898** for the nominated database. Allocating database file space in large 899** chunks (say 1MB at a time), may reduce file-system fragmentation and 900** improve performance on some systems. 901** 902** <li>[[SQLITE_FCNTL_FILE_POINTER]] 903** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 904** to the [sqlite3_file] object associated with a particular database 905** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 906** 907** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 908** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 909** to the [sqlite3_file] object associated with the journal file (either 910** the [rollback journal] or the [write-ahead log]) for a particular database 911** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 912** 913** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 914** No longer in use. 915** 916** <li>[[SQLITE_FCNTL_SYNC]] 917** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 918** sent to the VFS immediately before the xSync method is invoked on a 919** database file descriptor. Or, if the xSync method is not invoked 920** because the user has configured SQLite with 921** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 922** of the xSync method. In most cases, the pointer argument passed with 923** this file-control is NULL. However, if the database file is being synced 924** as part of a multi-database commit, the argument points to a nul-terminated 925** string containing the transactions super-journal file name. VFSes that 926** do not need this signal should silently ignore this opcode. Applications 927** should not call [sqlite3_file_control()] with this opcode as doing so may 928** disrupt the operation of the specialized VFSes that do require it. 929** 930** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 931** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 932** and sent to the VFS after a transaction has been committed immediately 933** but before the database is unlocked. VFSes that do not need this signal 934** should silently ignore this opcode. Applications should not call 935** [sqlite3_file_control()] with this opcode as doing so may disrupt the 936** operation of the specialized VFSes that do require it. 937** 938** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 939** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 940** retry counts and intervals for certain disk I/O operations for the 941** windows [VFS] in order to provide robustness in the presence of 942** anti-virus programs. By default, the windows VFS will retry file read, 943** file write, and file delete operations up to 10 times, with a delay 944** of 25 milliseconds before the first retry and with the delay increasing 945** by an additional 25 milliseconds with each subsequent retry. This 946** opcode allows these two values (10 retries and 25 milliseconds of delay) 947** to be adjusted. The values are changed for all database connections 948** within the same process. The argument is a pointer to an array of two 949** integers where the first integer is the new retry count and the second 950** integer is the delay. If either integer is negative, then the setting 951** is not changed but instead the prior value of that setting is written 952** into the array entry, allowing the current retry settings to be 953** interrogated. The zDbName parameter is ignored. 954** 955** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 956** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 957** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 958** write ahead log ([WAL file]) and shared memory 959** files used for transaction control 960** are automatically deleted when the latest connection to the database 961** closes. Setting persistent WAL mode causes those files to persist after 962** close. Persisting the files is useful when other processes that do not 963** have write permission on the directory containing the database file want 964** to read the database file, as the WAL and shared memory files must exist 965** in order for the database to be readable. The fourth parameter to 966** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 967** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 968** WAL mode. If the integer is -1, then it is overwritten with the current 969** WAL persistence setting. 970** 971** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 972** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 973** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 974** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 975** xDeviceCharacteristics methods. The fourth parameter to 976** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 977** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 978** mode. If the integer is -1, then it is overwritten with the current 979** zero-damage mode setting. 980** 981** <li>[[SQLITE_FCNTL_OVERWRITE]] 982** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 983** a write transaction to indicate that, unless it is rolled back for some 984** reason, the entire database file will be overwritten by the current 985** transaction. This is used by VACUUM operations. 986** 987** <li>[[SQLITE_FCNTL_VFSNAME]] 988** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 989** all [VFSes] in the VFS stack. The names are of all VFS shims and the 990** final bottom-level VFS are written into memory obtained from 991** [sqlite3_malloc()] and the result is stored in the char* variable 992** that the fourth parameter of [sqlite3_file_control()] points to. 993** The caller is responsible for freeing the memory when done. As with 994** all file-control actions, there is no guarantee that this will actually 995** do anything. Callers should initialize the char* variable to a NULL 996** pointer in case this file-control is not implemented. This file-control 997** is intended for diagnostic use only. 998** 999** <li>[[SQLITE_FCNTL_VFS_POINTER]] 1000** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 1001** [VFSes] currently in use. ^(The argument X in 1002** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 1003** of type "[sqlite3_vfs] **". This opcodes will set *X 1004** to a pointer to the top-level VFS.)^ 1005** ^When there are multiple VFS shims in the stack, this opcode finds the 1006** upper-most shim only. 1007** 1008** <li>[[SQLITE_FCNTL_PRAGMA]] 1009** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 1010** file control is sent to the open [sqlite3_file] object corresponding 1011** to the database file to which the pragma statement refers. ^The argument 1012** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 1013** pointers to strings (char**) in which the second element of the array 1014** is the name of the pragma and the third element is the argument to the 1015** pragma or NULL if the pragma has no argument. ^The handler for an 1016** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 1017** of the char** argument point to a string obtained from [sqlite3_mprintf()] 1018** or the equivalent and that string will become the result of the pragma or 1019** the error message if the pragma fails. ^If the 1020** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 1021** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 1022** file control returns [SQLITE_OK], then the parser assumes that the 1023** VFS has handled the PRAGMA itself and the parser generates a no-op 1024** prepared statement if result string is NULL, or that returns a copy 1025** of the result string if the string is non-NULL. 1026** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 1027** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 1028** that the VFS encountered an error while handling the [PRAGMA] and the 1029** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 1030** file control occurs at the beginning of pragma statement analysis and so 1031** it is able to override built-in [PRAGMA] statements. 1032** 1033** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 1034** ^The [SQLITE_FCNTL_BUSYHANDLER] 1035** file-control may be invoked by SQLite on the database file handle 1036** shortly after it is opened in order to provide a custom VFS with access 1037** to the connection's busy-handler callback. The argument is of type (void**) 1038** - an array of two (void *) values. The first (void *) actually points 1039** to a function of type (int (*)(void *)). In order to invoke the connection's 1040** busy-handler, this function should be invoked with the second (void *) in 1041** the array as the only argument. If it returns non-zero, then the operation 1042** should be retried. If it returns zero, the custom VFS should abandon the 1043** current operation. 1044** 1045** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 1046** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 1047** to have SQLite generate a 1048** temporary filename using the same algorithm that is followed to generate 1049** temporary filenames for TEMP tables and other internal uses. The 1050** argument should be a char** which will be filled with the filename 1051** written into memory obtained from [sqlite3_malloc()]. The caller should 1052** invoke [sqlite3_free()] on the result to avoid a memory leak. 1053** 1054** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1055** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1056** maximum number of bytes that will be used for memory-mapped I/O. 1057** The argument is a pointer to a value of type sqlite3_int64 that 1058** is an advisory maximum number of bytes in the file to memory map. The 1059** pointer is overwritten with the old value. The limit is not changed if 1060** the value originally pointed to is negative, and so the current limit 1061** can be queried by passing in a pointer to a negative number. This 1062** file-control is used internally to implement [PRAGMA mmap_size]. 1063** 1064** <li>[[SQLITE_FCNTL_TRACE]] 1065** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1066** to the VFS about what the higher layers of the SQLite stack are doing. 1067** This file control is used by some VFS activity tracing [shims]. 1068** The argument is a zero-terminated string. Higher layers in the 1069** SQLite stack may generate instances of this file control if 1070** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1071** 1072** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1073** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1074** pointer to an integer and it writes a boolean into that integer depending 1075** on whether or not the file has been renamed, moved, or deleted since it 1076** was first opened. 1077** 1078** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1079** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1080** underlying native file handle associated with a file handle. This file 1081** control interprets its argument as a pointer to a native file handle and 1082** writes the resulting value there. 1083** 1084** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1085** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1086** opcode causes the xFileControl method to swap the file handle with the one 1087** pointed to by the pArg argument. This capability is used during testing 1088** and only needs to be supported when SQLITE_TEST is defined. 1089** 1090** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1091** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1092** be advantageous to block on the next WAL lock if the lock is not immediately 1093** available. The WAL subsystem issues this signal during rare 1094** circumstances in order to fix a problem with priority inversion. 1095** Applications should <em>not</em> use this file-control. 1096** 1097** <li>[[SQLITE_FCNTL_ZIPVFS]] 1098** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1099** VFS should return SQLITE_NOTFOUND for this opcode. 1100** 1101** <li>[[SQLITE_FCNTL_RBU]] 1102** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1103** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1104** this opcode. 1105** 1106** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1107** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1108** the file descriptor is placed in "batch write mode", which 1109** means all subsequent write operations will be deferred and done 1110** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1111** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1112** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1113** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1114** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1115** no VFS interface calls on the same [sqlite3_file] file descriptor 1116** except for calls to the xWrite method and the xFileControl method 1117** with [SQLITE_FCNTL_SIZE_HINT]. 1118** 1119** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1120** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1121** operations since the previous successful call to 1122** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1123** This file control returns [SQLITE_OK] if and only if the writes were 1124** all performed successfully and have been committed to persistent storage. 1125** ^Regardless of whether or not it is successful, this file control takes 1126** the file descriptor out of batch write mode so that all subsequent 1127** write operations are independent. 1128** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1129** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1130** 1131** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1132** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1133** operations since the previous successful call to 1134** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1135** ^This file control takes the file descriptor out of batch write mode 1136** so that all subsequent write operations are independent. 1137** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1138** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1139** 1140** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1141** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1142** to block for up to M milliseconds before failing when attempting to 1143** obtain a file lock using the xLock or xShmLock methods of the VFS. 1144** The parameter is a pointer to a 32-bit signed integer that contains 1145** the value that M is to be set to. Before returning, the 32-bit signed 1146** integer is overwritten with the previous value of M. 1147** 1148** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1149** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1150** a database file. The argument is a pointer to a 32-bit unsigned integer. 1151** The "data version" for the pager is written into the pointer. The 1152** "data version" changes whenever any change occurs to the corresponding 1153** database file, either through SQL statements on the same database 1154** connection or through transactions committed by separate database 1155** connections possibly in other processes. The [sqlite3_total_changes()] 1156** interface can be used to find if any database on the connection has changed, 1157** but that interface responds to changes on TEMP as well as MAIN and does 1158** not provide a mechanism to detect changes to MAIN only. Also, the 1159** [sqlite3_total_changes()] interface responds to internal changes only and 1160** omits changes made by other database connections. The 1161** [PRAGMA data_version] command provides a mechanism to detect changes to 1162** a single attached database that occur due to other database connections, 1163** but omits changes implemented by the database connection on which it is 1164** called. This file control is the only mechanism to detect changes that 1165** happen either internally or externally and that are associated with 1166** a particular attached database. 1167** 1168** <li>[[SQLITE_FCNTL_CKPT_START]] 1169** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1170** in wal mode before the client starts to copy pages from the wal 1171** file to the database file. 1172** 1173** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1174** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1175** in wal mode after the client has finished copying pages from the wal 1176** file to the database file, but before the *-shm file is updated to 1177** record the fact that the pages have been checkpointed. 1178** </ul> 1179** 1180** <li>[[SQLITE_FCNTL_EXTERNAL_READER]] 1181** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect 1182** whether or not there is a database client in another process with a wal-mode 1183** transaction open on the database or not. It is only available on unix.The 1184** (void*) argument passed with this file-control should be a pointer to a 1185** value of type (int). The integer value is set to 1 if the database is a wal 1186** mode database and there exists at least one client in another process that 1187** currently has an SQL transaction open on the database. It is set to 0 if 1188** the database is not a wal-mode db, or if there is no such connection in any 1189** other process. This opcode cannot be used to detect transactions opened 1190** by clients within the current process, only within other processes. 1191** </ul> 1192** 1193** <li>[[SQLITE_FCNTL_CKSM_FILE]] 1194** Used by the cksmvfs VFS module only. 1195** </ul> 1196*/ 1197#define SQLITE_FCNTL_LOCKSTATE 1 1198#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1199#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1200#define SQLITE_FCNTL_LAST_ERRNO 4 1201#define SQLITE_FCNTL_SIZE_HINT 5 1202#define SQLITE_FCNTL_CHUNK_SIZE 6 1203#define SQLITE_FCNTL_FILE_POINTER 7 1204#define SQLITE_FCNTL_SYNC_OMITTED 8 1205#define SQLITE_FCNTL_WIN32_AV_RETRY 9 1206#define SQLITE_FCNTL_PERSIST_WAL 10 1207#define SQLITE_FCNTL_OVERWRITE 11 1208#define SQLITE_FCNTL_VFSNAME 12 1209#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1210#define SQLITE_FCNTL_PRAGMA 14 1211#define SQLITE_FCNTL_BUSYHANDLER 15 1212#define SQLITE_FCNTL_TEMPFILENAME 16 1213#define SQLITE_FCNTL_MMAP_SIZE 18 1214#define SQLITE_FCNTL_TRACE 19 1215#define SQLITE_FCNTL_HAS_MOVED 20 1216#define SQLITE_FCNTL_SYNC 21 1217#define SQLITE_FCNTL_COMMIT_PHASETWO 22 1218#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1219#define SQLITE_FCNTL_WAL_BLOCK 24 1220#define SQLITE_FCNTL_ZIPVFS 25 1221#define SQLITE_FCNTL_RBU 26 1222#define SQLITE_FCNTL_VFS_POINTER 27 1223#define SQLITE_FCNTL_JOURNAL_POINTER 28 1224#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1225#define SQLITE_FCNTL_PDB 30 1226#define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1227#define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1228#define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1229#define SQLITE_FCNTL_LOCK_TIMEOUT 34 1230#define SQLITE_FCNTL_DATA_VERSION 35 1231#define SQLITE_FCNTL_SIZE_LIMIT 36 1232#define SQLITE_FCNTL_CKPT_DONE 37 1233#define SQLITE_FCNTL_RESERVE_BYTES 38 1234#define SQLITE_FCNTL_CKPT_START 39 1235#define SQLITE_FCNTL_EXTERNAL_READER 40 1236#define SQLITE_FCNTL_CKSM_FILE 41 1237 1238/* deprecated names */ 1239#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1240#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1241#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1242 1243 1244/* 1245** CAPI3REF: Mutex Handle 1246** 1247** The mutex module within SQLite defines [sqlite3_mutex] to be an 1248** abstract type for a mutex object. The SQLite core never looks 1249** at the internal representation of an [sqlite3_mutex]. It only 1250** deals with pointers to the [sqlite3_mutex] object. 1251** 1252** Mutexes are created using [sqlite3_mutex_alloc()]. 1253*/ 1254typedef struct sqlite3_mutex sqlite3_mutex; 1255 1256/* 1257** CAPI3REF: Loadable Extension Thunk 1258** 1259** A pointer to the opaque sqlite3_api_routines structure is passed as 1260** the third parameter to entry points of [loadable extensions]. This 1261** structure must be typedefed in order to work around compiler warnings 1262** on some platforms. 1263*/ 1264typedef struct sqlite3_api_routines sqlite3_api_routines; 1265 1266/* 1267** CAPI3REF: OS Interface Object 1268** 1269** An instance of the sqlite3_vfs object defines the interface between 1270** the SQLite core and the underlying operating system. The "vfs" 1271** in the name of the object stands for "virtual file system". See 1272** the [VFS | VFS documentation] for further information. 1273** 1274** The VFS interface is sometimes extended by adding new methods onto 1275** the end. Each time such an extension occurs, the iVersion field 1276** is incremented. The iVersion value started out as 1 in 1277** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1278** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1279** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1280** may be appended to the sqlite3_vfs object and the iVersion value 1281** may increase again in future versions of SQLite. 1282** Note that due to an oversight, the structure 1283** of the sqlite3_vfs object changed in the transition from 1284** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1285** and yet the iVersion field was not increased. 1286** 1287** The szOsFile field is the size of the subclassed [sqlite3_file] 1288** structure used by this VFS. mxPathname is the maximum length of 1289** a pathname in this VFS. 1290** 1291** Registered sqlite3_vfs objects are kept on a linked list formed by 1292** the pNext pointer. The [sqlite3_vfs_register()] 1293** and [sqlite3_vfs_unregister()] interfaces manage this list 1294** in a thread-safe way. The [sqlite3_vfs_find()] interface 1295** searches the list. Neither the application code nor the VFS 1296** implementation should use the pNext pointer. 1297** 1298** The pNext field is the only field in the sqlite3_vfs 1299** structure that SQLite will ever modify. SQLite will only access 1300** or modify this field while holding a particular static mutex. 1301** The application should never modify anything within the sqlite3_vfs 1302** object once the object has been registered. 1303** 1304** The zName field holds the name of the VFS module. The name must 1305** be unique across all VFS modules. 1306** 1307** [[sqlite3_vfs.xOpen]] 1308** ^SQLite guarantees that the zFilename parameter to xOpen 1309** is either a NULL pointer or string obtained 1310** from xFullPathname() with an optional suffix added. 1311** ^If a suffix is added to the zFilename parameter, it will 1312** consist of a single "-" character followed by no more than 1313** 11 alphanumeric and/or "-" characters. 1314** ^SQLite further guarantees that 1315** the string will be valid and unchanged until xClose() is 1316** called. Because of the previous sentence, 1317** the [sqlite3_file] can safely store a pointer to the 1318** filename if it needs to remember the filename for some reason. 1319** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1320** must invent its own temporary name for the file. ^Whenever the 1321** xFilename parameter is NULL it will also be the case that the 1322** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1323** 1324** The flags argument to xOpen() includes all bits set in 1325** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1326** or [sqlite3_open16()] is used, then flags includes at least 1327** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1328** If xOpen() opens a file read-only then it sets *pOutFlags to 1329** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1330** 1331** ^(SQLite will also add one of the following flags to the xOpen() 1332** call, depending on the object being opened: 1333** 1334** <ul> 1335** <li> [SQLITE_OPEN_MAIN_DB] 1336** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1337** <li> [SQLITE_OPEN_TEMP_DB] 1338** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1339** <li> [SQLITE_OPEN_TRANSIENT_DB] 1340** <li> [SQLITE_OPEN_SUBJOURNAL] 1341** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1342** <li> [SQLITE_OPEN_WAL] 1343** </ul>)^ 1344** 1345** The file I/O implementation can use the object type flags to 1346** change the way it deals with files. For example, an application 1347** that does not care about crash recovery or rollback might make 1348** the open of a journal file a no-op. Writes to this journal would 1349** also be no-ops, and any attempt to read the journal would return 1350** SQLITE_IOERR. Or the implementation might recognize that a database 1351** file will be doing page-aligned sector reads and writes in a random 1352** order and set up its I/O subsystem accordingly. 1353** 1354** SQLite might also add one of the following flags to the xOpen method: 1355** 1356** <ul> 1357** <li> [SQLITE_OPEN_DELETEONCLOSE] 1358** <li> [SQLITE_OPEN_EXCLUSIVE] 1359** </ul> 1360** 1361** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1362** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1363** will be set for TEMP databases and their journals, transient 1364** databases, and subjournals. 1365** 1366** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1367** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1368** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1369** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1370** SQLITE_OPEN_CREATE, is used to indicate that file should always 1371** be created, and that it is an error if it already exists. 1372** It is <i>not</i> used to indicate the file should be opened 1373** for exclusive access. 1374** 1375** ^At least szOsFile bytes of memory are allocated by SQLite 1376** to hold the [sqlite3_file] structure passed as the third 1377** argument to xOpen. The xOpen method does not have to 1378** allocate the structure; it should just fill it in. Note that 1379** the xOpen method must set the sqlite3_file.pMethods to either 1380** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1381** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1382** element will be valid after xOpen returns regardless of the success 1383** or failure of the xOpen call. 1384** 1385** [[sqlite3_vfs.xAccess]] 1386** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1387** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1388** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1389** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1390** flag is never actually used and is not implemented in the built-in 1391** VFSes of SQLite. The file is named by the second argument and can be a 1392** directory. The xAccess method returns [SQLITE_OK] on success or some 1393** non-zero error code if there is an I/O error or if the name of 1394** the file given in the second argument is illegal. If SQLITE_OK 1395** is returned, then non-zero or zero is written into *pResOut to indicate 1396** whether or not the file is accessible. 1397** 1398** ^SQLite will always allocate at least mxPathname+1 bytes for the 1399** output buffer xFullPathname. The exact size of the output buffer 1400** is also passed as a parameter to both methods. If the output buffer 1401** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1402** handled as a fatal error by SQLite, vfs implementations should endeavor 1403** to prevent this by setting mxPathname to a sufficiently large value. 1404** 1405** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1406** interfaces are not strictly a part of the filesystem, but they are 1407** included in the VFS structure for completeness. 1408** The xRandomness() function attempts to return nBytes bytes 1409** of good-quality randomness into zOut. The return value is 1410** the actual number of bytes of randomness obtained. 1411** The xSleep() method causes the calling thread to sleep for at 1412** least the number of microseconds given. ^The xCurrentTime() 1413** method returns a Julian Day Number for the current date and time as 1414** a floating point value. 1415** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1416** Day Number multiplied by 86400000 (the number of milliseconds in 1417** a 24-hour day). 1418** ^SQLite will use the xCurrentTimeInt64() method to get the current 1419** date and time if that method is available (if iVersion is 2 or 1420** greater and the function pointer is not NULL) and will fall back 1421** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1422** 1423** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1424** are not used by the SQLite core. These optional interfaces are provided 1425** by some VFSes to facilitate testing of the VFS code. By overriding 1426** system calls with functions under its control, a test program can 1427** simulate faults and error conditions that would otherwise be difficult 1428** or impossible to induce. The set of system calls that can be overridden 1429** varies from one VFS to another, and from one version of the same VFS to the 1430** next. Applications that use these interfaces must be prepared for any 1431** or all of these interfaces to be NULL or for their behavior to change 1432** from one release to the next. Applications must not attempt to access 1433** any of these methods if the iVersion of the VFS is less than 3. 1434*/ 1435typedef struct sqlite3_vfs sqlite3_vfs; 1436typedef void (*sqlite3_syscall_ptr)(void); 1437struct sqlite3_vfs { 1438 int iVersion; /* Structure version number (currently 3) */ 1439 int szOsFile; /* Size of subclassed sqlite3_file */ 1440 int mxPathname; /* Maximum file pathname length */ 1441 sqlite3_vfs *pNext; /* Next registered VFS */ 1442 const char *zName; /* Name of this virtual file system */ 1443 void *pAppData; /* Pointer to application-specific data */ 1444 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 1445 int flags, int *pOutFlags); 1446 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1447 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1448 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1449 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1450 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1451 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1452 void (*xDlClose)(sqlite3_vfs*, void*); 1453 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1454 int (*xSleep)(sqlite3_vfs*, int microseconds); 1455 int (*xCurrentTime)(sqlite3_vfs*, double*); 1456 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1457 /* 1458 ** The methods above are in version 1 of the sqlite_vfs object 1459 ** definition. Those that follow are added in version 2 or later 1460 */ 1461 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1462 /* 1463 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1464 ** Those below are for version 3 and greater. 1465 */ 1466 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1467 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1468 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1469 /* 1470 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1471 ** New fields may be appended in future versions. The iVersion 1472 ** value will increment whenever this happens. 1473 */ 1474}; 1475 1476/* 1477** CAPI3REF: Flags for the xAccess VFS method 1478** 1479** These integer constants can be used as the third parameter to 1480** the xAccess method of an [sqlite3_vfs] object. They determine 1481** what kind of permissions the xAccess method is looking for. 1482** With SQLITE_ACCESS_EXISTS, the xAccess method 1483** simply checks whether the file exists. 1484** With SQLITE_ACCESS_READWRITE, the xAccess method 1485** checks whether the named directory is both readable and writable 1486** (in other words, if files can be added, removed, and renamed within 1487** the directory). 1488** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1489** [temp_store_directory pragma], though this could change in a future 1490** release of SQLite. 1491** With SQLITE_ACCESS_READ, the xAccess method 1492** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1493** currently unused, though it might be used in a future release of 1494** SQLite. 1495*/ 1496#define SQLITE_ACCESS_EXISTS 0 1497#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1498#define SQLITE_ACCESS_READ 2 /* Unused */ 1499 1500/* 1501** CAPI3REF: Flags for the xShmLock VFS method 1502** 1503** These integer constants define the various locking operations 1504** allowed by the xShmLock method of [sqlite3_io_methods]. The 1505** following are the only legal combinations of flags to the 1506** xShmLock method: 1507** 1508** <ul> 1509** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1510** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1511** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1512** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1513** </ul> 1514** 1515** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1516** was given on the corresponding lock. 1517** 1518** The xShmLock method can transition between unlocked and SHARED or 1519** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1520** and EXCLUSIVE. 1521*/ 1522#define SQLITE_SHM_UNLOCK 1 1523#define SQLITE_SHM_LOCK 2 1524#define SQLITE_SHM_SHARED 4 1525#define SQLITE_SHM_EXCLUSIVE 8 1526 1527/* 1528** CAPI3REF: Maximum xShmLock index 1529** 1530** The xShmLock method on [sqlite3_io_methods] may use values 1531** between 0 and this upper bound as its "offset" argument. 1532** The SQLite core will never attempt to acquire or release a 1533** lock outside of this range 1534*/ 1535#define SQLITE_SHM_NLOCK 8 1536 1537 1538/* 1539** CAPI3REF: Initialize The SQLite Library 1540** 1541** ^The sqlite3_initialize() routine initializes the 1542** SQLite library. ^The sqlite3_shutdown() routine 1543** deallocates any resources that were allocated by sqlite3_initialize(). 1544** These routines are designed to aid in process initialization and 1545** shutdown on embedded systems. Workstation applications using 1546** SQLite normally do not need to invoke either of these routines. 1547** 1548** A call to sqlite3_initialize() is an "effective" call if it is 1549** the first time sqlite3_initialize() is invoked during the lifetime of 1550** the process, or if it is the first time sqlite3_initialize() is invoked 1551** following a call to sqlite3_shutdown(). ^(Only an effective call 1552** of sqlite3_initialize() does any initialization. All other calls 1553** are harmless no-ops.)^ 1554** 1555** A call to sqlite3_shutdown() is an "effective" call if it is the first 1556** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1557** an effective call to sqlite3_shutdown() does any deinitialization. 1558** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1559** 1560** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1561** is not. The sqlite3_shutdown() interface must only be called from a 1562** single thread. All open [database connections] must be closed and all 1563** other SQLite resources must be deallocated prior to invoking 1564** sqlite3_shutdown(). 1565** 1566** Among other things, ^sqlite3_initialize() will invoke 1567** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1568** will invoke sqlite3_os_end(). 1569** 1570** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1571** ^If for some reason, sqlite3_initialize() is unable to initialize 1572** the library (perhaps it is unable to allocate a needed resource such 1573** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1574** 1575** ^The sqlite3_initialize() routine is called internally by many other 1576** SQLite interfaces so that an application usually does not need to 1577** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1578** calls sqlite3_initialize() so the SQLite library will be automatically 1579** initialized when [sqlite3_open()] is called if it has not be initialized 1580** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1581** compile-time option, then the automatic calls to sqlite3_initialize() 1582** are omitted and the application must call sqlite3_initialize() directly 1583** prior to using any other SQLite interface. For maximum portability, 1584** it is recommended that applications always invoke sqlite3_initialize() 1585** directly prior to using any other SQLite interface. Future releases 1586** of SQLite may require this. In other words, the behavior exhibited 1587** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1588** default behavior in some future release of SQLite. 1589** 1590** The sqlite3_os_init() routine does operating-system specific 1591** initialization of the SQLite library. The sqlite3_os_end() 1592** routine undoes the effect of sqlite3_os_init(). Typical tasks 1593** performed by these routines include allocation or deallocation 1594** of static resources, initialization of global variables, 1595** setting up a default [sqlite3_vfs] module, or setting up 1596** a default configuration using [sqlite3_config()]. 1597** 1598** The application should never invoke either sqlite3_os_init() 1599** or sqlite3_os_end() directly. The application should only invoke 1600** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1601** interface is called automatically by sqlite3_initialize() and 1602** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1603** implementations for sqlite3_os_init() and sqlite3_os_end() 1604** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1605** When [custom builds | built for other platforms] 1606** (using the [SQLITE_OS_OTHER=1] compile-time 1607** option) the application must supply a suitable implementation for 1608** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1609** implementation of sqlite3_os_init() or sqlite3_os_end() 1610** must return [SQLITE_OK] on success and some other [error code] upon 1611** failure. 1612*/ 1613int sqlite3_initialize(void); 1614int sqlite3_shutdown(void); 1615int sqlite3_os_init(void); 1616int sqlite3_os_end(void); 1617 1618/* 1619** CAPI3REF: Configuring The SQLite Library 1620** 1621** The sqlite3_config() interface is used to make global configuration 1622** changes to SQLite in order to tune SQLite to the specific needs of 1623** the application. The default configuration is recommended for most 1624** applications and so this routine is usually not necessary. It is 1625** provided to support rare applications with unusual needs. 1626** 1627** <b>The sqlite3_config() interface is not threadsafe. The application 1628** must ensure that no other SQLite interfaces are invoked by other 1629** threads while sqlite3_config() is running.</b> 1630** 1631** The sqlite3_config() interface 1632** may only be invoked prior to library initialization using 1633** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1634** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1635** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1636** Note, however, that ^sqlite3_config() can be called as part of the 1637** implementation of an application-defined [sqlite3_os_init()]. 1638** 1639** The first argument to sqlite3_config() is an integer 1640** [configuration option] that determines 1641** what property of SQLite is to be configured. Subsequent arguments 1642** vary depending on the [configuration option] 1643** in the first argument. 1644** 1645** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1646** ^If the option is unknown or SQLite is unable to set the option 1647** then this routine returns a non-zero [error code]. 1648*/ 1649int sqlite3_config(int, ...); 1650 1651/* 1652** CAPI3REF: Configure database connections 1653** METHOD: sqlite3 1654** 1655** The sqlite3_db_config() interface is used to make configuration 1656** changes to a [database connection]. The interface is similar to 1657** [sqlite3_config()] except that the changes apply to a single 1658** [database connection] (specified in the first argument). 1659** 1660** The second argument to sqlite3_db_config(D,V,...) is the 1661** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1662** that indicates what aspect of the [database connection] is being configured. 1663** Subsequent arguments vary depending on the configuration verb. 1664** 1665** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1666** the call is considered successful. 1667*/ 1668int sqlite3_db_config(sqlite3*, int op, ...); 1669 1670/* 1671** CAPI3REF: Memory Allocation Routines 1672** 1673** An instance of this object defines the interface between SQLite 1674** and low-level memory allocation routines. 1675** 1676** This object is used in only one place in the SQLite interface. 1677** A pointer to an instance of this object is the argument to 1678** [sqlite3_config()] when the configuration option is 1679** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1680** By creating an instance of this object 1681** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1682** during configuration, an application can specify an alternative 1683** memory allocation subsystem for SQLite to use for all of its 1684** dynamic memory needs. 1685** 1686** Note that SQLite comes with several [built-in memory allocators] 1687** that are perfectly adequate for the overwhelming majority of applications 1688** and that this object is only useful to a tiny minority of applications 1689** with specialized memory allocation requirements. This object is 1690** also used during testing of SQLite in order to specify an alternative 1691** memory allocator that simulates memory out-of-memory conditions in 1692** order to verify that SQLite recovers gracefully from such 1693** conditions. 1694** 1695** The xMalloc, xRealloc, and xFree methods must work like the 1696** malloc(), realloc() and free() functions from the standard C library. 1697** ^SQLite guarantees that the second argument to 1698** xRealloc is always a value returned by a prior call to xRoundup. 1699** 1700** xSize should return the allocated size of a memory allocation 1701** previously obtained from xMalloc or xRealloc. The allocated size 1702** is always at least as big as the requested size but may be larger. 1703** 1704** The xRoundup method returns what would be the allocated size of 1705** a memory allocation given a particular requested size. Most memory 1706** allocators round up memory allocations at least to the next multiple 1707** of 8. Some allocators round up to a larger multiple or to a power of 2. 1708** Every memory allocation request coming in through [sqlite3_malloc()] 1709** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1710** that causes the corresponding memory allocation to fail. 1711** 1712** The xInit method initializes the memory allocator. For example, 1713** it might allocate any required mutexes or initialize internal data 1714** structures. The xShutdown method is invoked (indirectly) by 1715** [sqlite3_shutdown()] and should deallocate any resources acquired 1716** by xInit. The pAppData pointer is used as the only parameter to 1717** xInit and xShutdown. 1718** 1719** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1720** the xInit method, so the xInit method need not be threadsafe. The 1721** xShutdown method is only called from [sqlite3_shutdown()] so it does 1722** not need to be threadsafe either. For all other methods, SQLite 1723** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1724** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1725** it is by default) and so the methods are automatically serialized. 1726** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1727** methods must be threadsafe or else make their own arrangements for 1728** serialization. 1729** 1730** SQLite will never invoke xInit() more than once without an intervening 1731** call to xShutdown(). 1732*/ 1733typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1734struct sqlite3_mem_methods { 1735 void *(*xMalloc)(int); /* Memory allocation function */ 1736 void (*xFree)(void*); /* Free a prior allocation */ 1737 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1738 int (*xSize)(void*); /* Return the size of an allocation */ 1739 int (*xRoundup)(int); /* Round up request size to allocation size */ 1740 int (*xInit)(void*); /* Initialize the memory allocator */ 1741 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1742 void *pAppData; /* Argument to xInit() and xShutdown() */ 1743}; 1744 1745/* 1746** CAPI3REF: Configuration Options 1747** KEYWORDS: {configuration option} 1748** 1749** These constants are the available integer configuration options that 1750** can be passed as the first argument to the [sqlite3_config()] interface. 1751** 1752** New configuration options may be added in future releases of SQLite. 1753** Existing configuration options might be discontinued. Applications 1754** should check the return code from [sqlite3_config()] to make sure that 1755** the call worked. The [sqlite3_config()] interface will return a 1756** non-zero [error code] if a discontinued or unsupported configuration option 1757** is invoked. 1758** 1759** <dl> 1760** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1761** <dd>There are no arguments to this option. ^This option sets the 1762** [threading mode] to Single-thread. In other words, it disables 1763** all mutexing and puts SQLite into a mode where it can only be used 1764** by a single thread. ^If SQLite is compiled with 1765** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1766** it is not possible to change the [threading mode] from its default 1767** value of Single-thread and so [sqlite3_config()] will return 1768** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1769** configuration option.</dd> 1770** 1771** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1772** <dd>There are no arguments to this option. ^This option sets the 1773** [threading mode] to Multi-thread. In other words, it disables 1774** mutexing on [database connection] and [prepared statement] objects. 1775** The application is responsible for serializing access to 1776** [database connections] and [prepared statements]. But other mutexes 1777** are enabled so that SQLite will be safe to use in a multi-threaded 1778** environment as long as no two threads attempt to use the same 1779** [database connection] at the same time. ^If SQLite is compiled with 1780** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1781** it is not possible to set the Multi-thread [threading mode] and 1782** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1783** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1784** 1785** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1786** <dd>There are no arguments to this option. ^This option sets the 1787** [threading mode] to Serialized. In other words, this option enables 1788** all mutexes including the recursive 1789** mutexes on [database connection] and [prepared statement] objects. 1790** In this mode (which is the default when SQLite is compiled with 1791** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1792** to [database connections] and [prepared statements] so that the 1793** application is free to use the same [database connection] or the 1794** same [prepared statement] in different threads at the same time. 1795** ^If SQLite is compiled with 1796** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1797** it is not possible to set the Serialized [threading mode] and 1798** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1799** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1800** 1801** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1802** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1803** a pointer to an instance of the [sqlite3_mem_methods] structure. 1804** The argument specifies 1805** alternative low-level memory allocation routines to be used in place of 1806** the memory allocation routines built into SQLite.)^ ^SQLite makes 1807** its own private copy of the content of the [sqlite3_mem_methods] structure 1808** before the [sqlite3_config()] call returns.</dd> 1809** 1810** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1811** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1812** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1813** The [sqlite3_mem_methods] 1814** structure is filled with the currently defined memory allocation routines.)^ 1815** This option can be used to overload the default memory allocation 1816** routines with a wrapper that simulations memory allocation failure or 1817** tracks memory usage, for example. </dd> 1818** 1819** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1820** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1821** type int, interpreted as a boolean, which if true provides a hint to 1822** SQLite that it should avoid large memory allocations if possible. 1823** SQLite will run faster if it is free to make large memory allocations, 1824** but some application might prefer to run slower in exchange for 1825** guarantees about memory fragmentation that are possible if large 1826** allocations are avoided. This hint is normally off. 1827** </dd> 1828** 1829** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1830** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1831** interpreted as a boolean, which enables or disables the collection of 1832** memory allocation statistics. ^(When memory allocation statistics are 1833** disabled, the following SQLite interfaces become non-operational: 1834** <ul> 1835** <li> [sqlite3_hard_heap_limit64()] 1836** <li> [sqlite3_memory_used()] 1837** <li> [sqlite3_memory_highwater()] 1838** <li> [sqlite3_soft_heap_limit64()] 1839** <li> [sqlite3_status64()] 1840** </ul>)^ 1841** ^Memory allocation statistics are enabled by default unless SQLite is 1842** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1843** allocation statistics are disabled by default. 1844** </dd> 1845** 1846** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1847** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1848** </dd> 1849** 1850** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1851** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1852** that SQLite can use for the database page cache with the default page 1853** cache implementation. 1854** This configuration option is a no-op if an application-defined page 1855** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1856** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1857** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1858** and the number of cache lines (N). 1859** The sz argument should be the size of the largest database page 1860** (a power of two between 512 and 65536) plus some extra bytes for each 1861** page header. ^The number of extra bytes needed by the page header 1862** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1863** ^It is harmless, apart from the wasted memory, 1864** for the sz parameter to be larger than necessary. The pMem 1865** argument must be either a NULL pointer or a pointer to an 8-byte 1866** aligned block of memory of at least sz*N bytes, otherwise 1867** subsequent behavior is undefined. 1868** ^When pMem is not NULL, SQLite will strive to use the memory provided 1869** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1870** a page cache line is larger than sz bytes or if all of the pMem buffer 1871** is exhausted. 1872** ^If pMem is NULL and N is non-zero, then each database connection 1873** does an initial bulk allocation for page cache memory 1874** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1875** of -1024*N bytes if N is negative, . ^If additional 1876** page cache memory is needed beyond what is provided by the initial 1877** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1878** additional cache line. </dd> 1879** 1880** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1881** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1882** that SQLite will use for all of its dynamic memory allocation needs 1883** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1884** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1885** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1886** [SQLITE_ERROR] if invoked otherwise. 1887** ^There are three arguments to SQLITE_CONFIG_HEAP: 1888** An 8-byte aligned pointer to the memory, 1889** the number of bytes in the memory buffer, and the minimum allocation size. 1890** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1891** to using its default memory allocator (the system malloc() implementation), 1892** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1893** memory pointer is not NULL then the alternative memory 1894** allocator is engaged to handle all of SQLites memory allocation needs. 1895** The first pointer (the memory pointer) must be aligned to an 8-byte 1896** boundary or subsequent behavior of SQLite will be undefined. 1897** The minimum allocation size is capped at 2**12. Reasonable values 1898** for the minimum allocation size are 2**5 through 2**8.</dd> 1899** 1900** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1901** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1902** pointer to an instance of the [sqlite3_mutex_methods] structure. 1903** The argument specifies alternative low-level mutex routines to be used 1904** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1905** the content of the [sqlite3_mutex_methods] structure before the call to 1906** [sqlite3_config()] returns. ^If SQLite is compiled with 1907** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1908** the entire mutexing subsystem is omitted from the build and hence calls to 1909** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1910** return [SQLITE_ERROR].</dd> 1911** 1912** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1913** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1914** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1915** [sqlite3_mutex_methods] 1916** structure is filled with the currently defined mutex routines.)^ 1917** This option can be used to overload the default mutex allocation 1918** routines with a wrapper used to track mutex usage for performance 1919** profiling or testing, for example. ^If SQLite is compiled with 1920** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1921** the entire mutexing subsystem is omitted from the build and hence calls to 1922** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1923** return [SQLITE_ERROR].</dd> 1924** 1925** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1926** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1927** the default size of lookaside memory on each [database connection]. 1928** The first argument is the 1929** size of each lookaside buffer slot and the second is the number of 1930** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1931** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1932** option to [sqlite3_db_config()] can be used to change the lookaside 1933** configuration on individual connections.)^ </dd> 1934** 1935** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1936** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1937** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1938** the interface to a custom page cache implementation.)^ 1939** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1940** 1941** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1942** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1943** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1944** the current page cache implementation into that object.)^ </dd> 1945** 1946** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1947** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1948** global [error log]. 1949** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1950** function with a call signature of void(*)(void*,int,const char*), 1951** and a pointer to void. ^If the function pointer is not NULL, it is 1952** invoked by [sqlite3_log()] to process each logging event. ^If the 1953** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1954** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1955** passed through as the first parameter to the application-defined logger 1956** function whenever that function is invoked. ^The second parameter to 1957** the logger function is a copy of the first parameter to the corresponding 1958** [sqlite3_log()] call and is intended to be a [result code] or an 1959** [extended result code]. ^The third parameter passed to the logger is 1960** log message after formatting via [sqlite3_snprintf()]. 1961** The SQLite logging interface is not reentrant; the logger function 1962** supplied by the application must not invoke any SQLite interface. 1963** In a multi-threaded application, the application-defined logger 1964** function must be threadsafe. </dd> 1965** 1966** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1967** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1968** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1969** then URI handling is globally disabled.)^ ^If URI handling is globally 1970** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1971** [sqlite3_open16()] or 1972** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1973** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1974** connection is opened. ^If it is globally disabled, filenames are 1975** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1976** database connection is opened. ^(By default, URI handling is globally 1977** disabled. The default value may be changed by compiling with the 1978** [SQLITE_USE_URI] symbol defined.)^ 1979** 1980** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 1981** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 1982** argument which is interpreted as a boolean in order to enable or disable 1983** the use of covering indices for full table scans in the query optimizer. 1984** ^The default setting is determined 1985** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 1986** if that compile-time option is omitted. 1987** The ability to disable the use of covering indices for full table scans 1988** is because some incorrectly coded legacy applications might malfunction 1989** when the optimization is enabled. Providing the ability to 1990** disable the optimization allows the older, buggy application code to work 1991** without change even with newer versions of SQLite. 1992** 1993** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 1994** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 1995** <dd> These options are obsolete and should not be used by new code. 1996** They are retained for backwards compatibility but are now no-ops. 1997** </dd> 1998** 1999** [[SQLITE_CONFIG_SQLLOG]] 2000** <dt>SQLITE_CONFIG_SQLLOG 2001** <dd>This option is only available if sqlite is compiled with the 2002** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 2003** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 2004** The second should be of type (void*). The callback is invoked by the library 2005** in three separate circumstances, identified by the value passed as the 2006** fourth parameter. If the fourth parameter is 0, then the database connection 2007** passed as the second argument has just been opened. The third argument 2008** points to a buffer containing the name of the main database file. If the 2009** fourth parameter is 1, then the SQL statement that the third parameter 2010** points to has just been executed. Or, if the fourth parameter is 2, then 2011** the connection being passed as the second parameter is being closed. The 2012** third parameter is passed NULL In this case. An example of using this 2013** configuration option can be seen in the "test_sqllog.c" source file in 2014** the canonical SQLite source tree.</dd> 2015** 2016** [[SQLITE_CONFIG_MMAP_SIZE]] 2017** <dt>SQLITE_CONFIG_MMAP_SIZE 2018** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 2019** that are the default mmap size limit (the default setting for 2020** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 2021** ^The default setting can be overridden by each database connection using 2022** either the [PRAGMA mmap_size] command, or by using the 2023** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 2024** will be silently truncated if necessary so that it does not exceed the 2025** compile-time maximum mmap size set by the 2026** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 2027** ^If either argument to this option is negative, then that argument is 2028** changed to its compile-time default. 2029** 2030** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 2031** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 2032** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 2033** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 2034** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 2035** that specifies the maximum size of the created heap. 2036** 2037** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 2038** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 2039** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 2040** is a pointer to an integer and writes into that integer the number of extra 2041** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 2042** The amount of extra space required can change depending on the compiler, 2043** target platform, and SQLite version. 2044** 2045** [[SQLITE_CONFIG_PMASZ]] 2046** <dt>SQLITE_CONFIG_PMASZ 2047** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 2048** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 2049** sorter to that integer. The default minimum PMA Size is set by the 2050** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 2051** to help with sort operations when multithreaded sorting 2052** is enabled (using the [PRAGMA threads] command) and the amount of content 2053** to be sorted exceeds the page size times the minimum of the 2054** [PRAGMA cache_size] setting and this value. 2055** 2056** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 2057** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 2058** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 2059** becomes the [statement journal] spill-to-disk threshold. 2060** [Statement journals] are held in memory until their size (in bytes) 2061** exceeds this threshold, at which point they are written to disk. 2062** Or if the threshold is -1, statement journals are always held 2063** exclusively in memory. 2064** Since many statement journals never become large, setting the spill 2065** threshold to a value such as 64KiB can greatly reduce the amount of 2066** I/O required to support statement rollback. 2067** The default value for this setting is controlled by the 2068** [SQLITE_STMTJRNL_SPILL] compile-time option. 2069** 2070** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2071** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2072** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2073** of type (int) - the new value of the sorter-reference size threshold. 2074** Usually, when SQLite uses an external sort to order records according 2075** to an ORDER BY clause, all fields required by the caller are present in the 2076** sorted records. However, if SQLite determines based on the declared type 2077** of a table column that its values are likely to be very large - larger 2078** than the configured sorter-reference size threshold - then a reference 2079** is stored in each sorted record and the required column values loaded 2080** from the database as records are returned in sorted order. The default 2081** value for this option is to never use this optimization. Specifying a 2082** negative value for this option restores the default behaviour. 2083** This option is only available if SQLite is compiled with the 2084** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2085** 2086** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2087** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2088** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2089** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2090** database created using [sqlite3_deserialize()]. This default maximum 2091** size can be adjusted up or down for individual databases using the 2092** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2093** configuration setting is never used, then the default maximum is determined 2094** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2095** compile-time option is not set, then the default maximum is 1073741824. 2096** </dl> 2097*/ 2098#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2099#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2100#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2101#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2102#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2103#define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2104#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2105#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2106#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2107#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2108#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2109/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2110#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2111#define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2112#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2113#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2114#define SQLITE_CONFIG_URI 17 /* int */ 2115#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2116#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2117#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2118#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2119#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2120#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2121#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2122#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2123#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2124#define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2125#define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2126#define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2127 2128/* 2129** CAPI3REF: Database Connection Configuration Options 2130** 2131** These constants are the available integer configuration options that 2132** can be passed as the second argument to the [sqlite3_db_config()] interface. 2133** 2134** New configuration options may be added in future releases of SQLite. 2135** Existing configuration options might be discontinued. Applications 2136** should check the return code from [sqlite3_db_config()] to make sure that 2137** the call worked. ^The [sqlite3_db_config()] interface will return a 2138** non-zero [error code] if a discontinued or unsupported configuration option 2139** is invoked. 2140** 2141** <dl> 2142** [[SQLITE_DBCONFIG_LOOKASIDE]] 2143** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2144** <dd> ^This option takes three additional arguments that determine the 2145** [lookaside memory allocator] configuration for the [database connection]. 2146** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2147** pointer to a memory buffer to use for lookaside memory. 2148** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2149** may be NULL in which case SQLite will allocate the 2150** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2151** size of each lookaside buffer slot. ^The third argument is the number of 2152** slots. The size of the buffer in the first argument must be greater than 2153** or equal to the product of the second and third arguments. The buffer 2154** must be aligned to an 8-byte boundary. ^If the second argument to 2155** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2156** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2157** configuration for a database connection can only be changed when that 2158** connection is not currently using lookaside memory, or in other words 2159** when the "current value" returned by 2160** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 2161** Any attempt to change the lookaside memory configuration when lookaside 2162** memory is in use leaves the configuration unchanged and returns 2163** [SQLITE_BUSY].)^</dd> 2164** 2165** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2166** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2167** <dd> ^This option is used to enable or disable the enforcement of 2168** [foreign key constraints]. There should be two additional arguments. 2169** The first argument is an integer which is 0 to disable FK enforcement, 2170** positive to enable FK enforcement or negative to leave FK enforcement 2171** unchanged. The second parameter is a pointer to an integer into which 2172** is written 0 or 1 to indicate whether FK enforcement is off or on 2173** following this call. The second parameter may be a NULL pointer, in 2174** which case the FK enforcement setting is not reported back. </dd> 2175** 2176** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2177** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2178** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2179** There should be two additional arguments. 2180** The first argument is an integer which is 0 to disable triggers, 2181** positive to enable triggers or negative to leave the setting unchanged. 2182** The second parameter is a pointer to an integer into which 2183** is written 0 or 1 to indicate whether triggers are disabled or enabled 2184** following this call. The second parameter may be a NULL pointer, in 2185** which case the trigger setting is not reported back. 2186** 2187** <p>Originally this option disabled all triggers. ^(However, since 2188** SQLite version 3.35.0, TEMP triggers are still allowed even if 2189** this option is off. So, in other words, this option now only disables 2190** triggers in the main database schema or in the schemas of ATTACH-ed 2191** databases.)^ </dd> 2192** 2193** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2194** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2195** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2196** There should be two additional arguments. 2197** The first argument is an integer which is 0 to disable views, 2198** positive to enable views or negative to leave the setting unchanged. 2199** The second parameter is a pointer to an integer into which 2200** is written 0 or 1 to indicate whether views are disabled or enabled 2201** following this call. The second parameter may be a NULL pointer, in 2202** which case the view setting is not reported back. 2203** 2204** <p>Originally this option disabled all views. ^(However, since 2205** SQLite version 3.35.0, TEMP views are still allowed even if 2206** this option is off. So, in other words, this option now only disables 2207** views in the main database schema or in the schemas of ATTACH-ed 2208** databases.)^ </dd> 2209** 2210** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2211** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2212** <dd> ^This option is used to enable or disable the 2213** [fts3_tokenizer()] function which is part of the 2214** [FTS3] full-text search engine extension. 2215** There should be two additional arguments. 2216** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2217** positive to enable fts3_tokenizer() or negative to leave the setting 2218** unchanged. 2219** The second parameter is a pointer to an integer into which 2220** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2221** following this call. The second parameter may be a NULL pointer, in 2222** which case the new setting is not reported back. </dd> 2223** 2224** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2225** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2226** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2227** interface independently of the [load_extension()] SQL function. 2228** The [sqlite3_enable_load_extension()] API enables or disables both the 2229** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2230** There should be two additional arguments. 2231** When the first argument to this interface is 1, then only the C-API is 2232** enabled and the SQL function remains disabled. If the first argument to 2233** this interface is 0, then both the C-API and the SQL function are disabled. 2234** If the first argument is -1, then no changes are made to state of either the 2235** C-API or the SQL function. 2236** The second parameter is a pointer to an integer into which 2237** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2238** is disabled or enabled following this call. The second parameter may 2239** be a NULL pointer, in which case the new setting is not reported back. 2240** </dd> 2241** 2242** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2243** <dd> ^This option is used to change the name of the "main" database 2244** schema. ^The sole argument is a pointer to a constant UTF8 string 2245** which will become the new schema name in place of "main". ^SQLite 2246** does not make a copy of the new main schema name string, so the application 2247** must ensure that the argument passed into this DBCONFIG option is unchanged 2248** until after the database connection closes. 2249** </dd> 2250** 2251** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2252** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2253** <dd> Usually, when a database in wal mode is closed or detached from a 2254** database handle, SQLite checks if this will mean that there are now no 2255** connections at all to the database. If so, it performs a checkpoint 2256** operation before closing the connection. This option may be used to 2257** override this behaviour. The first parameter passed to this operation 2258** is an integer - positive to disable checkpoints-on-close, or zero (the 2259** default) to enable them, and negative to leave the setting unchanged. 2260** The second parameter is a pointer to an integer 2261** into which is written 0 or 1 to indicate whether checkpoints-on-close 2262** have been disabled - 0 if they are not disabled, 1 if they are. 2263** </dd> 2264** 2265** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2266** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2267** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2268** a single SQL query statement will always use the same algorithm regardless 2269** of values of [bound parameters].)^ The QPSG disables some query optimizations 2270** that look at the values of bound parameters, which can make some queries 2271** slower. But the QPSG has the advantage of more predictable behavior. With 2272** the QPSG active, SQLite will always use the same query plan in the field as 2273** was used during testing in the lab. 2274** The first argument to this setting is an integer which is 0 to disable 2275** the QPSG, positive to enable QPSG, or negative to leave the setting 2276** unchanged. The second parameter is a pointer to an integer into which 2277** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2278** following this call. 2279** </dd> 2280** 2281** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2282** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2283** include output for any operations performed by trigger programs. This 2284** option is used to set or clear (the default) a flag that governs this 2285** behavior. The first parameter passed to this operation is an integer - 2286** positive to enable output for trigger programs, or zero to disable it, 2287** or negative to leave the setting unchanged. 2288** The second parameter is a pointer to an integer into which is written 2289** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2290** it is not disabled, 1 if it is. 2291** </dd> 2292** 2293** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2294** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2295** [VACUUM] in order to reset a database back to an empty database 2296** with no schema and no content. The following process works even for 2297** a badly corrupted database file: 2298** <ol> 2299** <li> If the database connection is newly opened, make sure it has read the 2300** database schema by preparing then discarding some query against the 2301** database, or calling sqlite3_table_column_metadata(), ignoring any 2302** errors. This step is only necessary if the application desires to keep 2303** the database in WAL mode after the reset if it was in WAL mode before 2304** the reset. 2305** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2306** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2307** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2308** </ol> 2309** Because resetting a database is destructive and irreversible, the 2310** process requires the use of this obscure API and multiple steps to help 2311** ensure that it does not happen by accident. 2312** 2313** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2314** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2315** "defensive" flag for a database connection. When the defensive 2316** flag is enabled, language features that allow ordinary SQL to 2317** deliberately corrupt the database file are disabled. The disabled 2318** features include but are not limited to the following: 2319** <ul> 2320** <li> The [PRAGMA writable_schema=ON] statement. 2321** <li> The [PRAGMA journal_mode=OFF] statement. 2322** <li> Writes to the [sqlite_dbpage] virtual table. 2323** <li> Direct writes to [shadow tables]. 2324** </ul> 2325** </dd> 2326** 2327** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2328** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2329** "writable_schema" flag. This has the same effect and is logically equivalent 2330** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2331** The first argument to this setting is an integer which is 0 to disable 2332** the writable_schema, positive to enable writable_schema, or negative to 2333** leave the setting unchanged. The second parameter is a pointer to an 2334** integer into which is written 0 or 1 to indicate whether the writable_schema 2335** is enabled or disabled following this call. 2336** </dd> 2337** 2338** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2339** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2340** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2341** the legacy behavior of the [ALTER TABLE RENAME] command such it 2342** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2343** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2344** additional information. This feature can also be turned on and off 2345** using the [PRAGMA legacy_alter_table] statement. 2346** </dd> 2347** 2348** [[SQLITE_DBCONFIG_DQS_DML]] 2349** <dt>SQLITE_DBCONFIG_DQS_DML</td> 2350** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2351** the legacy [double-quoted string literal] misfeature for DML statements 2352** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2353** default value of this setting is determined by the [-DSQLITE_DQS] 2354** compile-time option. 2355** </dd> 2356** 2357** [[SQLITE_DBCONFIG_DQS_DDL]] 2358** <dt>SQLITE_DBCONFIG_DQS_DDL</td> 2359** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2360** the legacy [double-quoted string literal] misfeature for DDL statements, 2361** such as CREATE TABLE and CREATE INDEX. The 2362** default value of this setting is determined by the [-DSQLITE_DQS] 2363** compile-time option. 2364** </dd> 2365** 2366** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2367** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td> 2368** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2369** assume that database schemas are untainted by malicious content. 2370** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2371** takes additional defensive steps to protect the application from harm 2372** including: 2373** <ul> 2374** <li> Prohibit the use of SQL functions inside triggers, views, 2375** CHECK constraints, DEFAULT clauses, expression indexes, 2376** partial indexes, or generated columns 2377** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2378** <li> Prohibit the use of virtual tables inside of triggers or views 2379** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2380** </ul> 2381** This setting defaults to "on" for legacy compatibility, however 2382** all applications are advised to turn it off if possible. This setting 2383** can also be controlled using the [PRAGMA trusted_schema] statement. 2384** </dd> 2385** 2386** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2387** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td> 2388** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2389** the legacy file format flag. When activated, this flag causes all newly 2390** created database file to have a schema format version number (the 4-byte 2391** integer found at offset 44 into the database header) of 1. This in turn 2392** means that the resulting database file will be readable and writable by 2393** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2394** newly created databases are generally not understandable by SQLite versions 2395** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2396** is now scarcely any need to generated database files that are compatible 2397** all the way back to version 3.0.0, and so this setting is of little 2398** practical use, but is provided so that SQLite can continue to claim the 2399** ability to generate new database files that are compatible with version 2400** 3.0.0. 2401** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2402** the [VACUUM] command will fail with an obscure error when attempting to 2403** process a table with generated columns and a descending index. This is 2404** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2405** either generated columns or decending indexes. 2406** </dd> 2407** </dl> 2408*/ 2409#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2410#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2411#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2412#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2413#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2414#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2415#define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2416#define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2417#define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2418#define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2419#define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2420#define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2421#define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2422#define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2423#define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2424#define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2425#define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2426#define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2427#define SQLITE_DBCONFIG_MAX 1017 /* Largest DBCONFIG */ 2428 2429/* 2430** CAPI3REF: Enable Or Disable Extended Result Codes 2431** METHOD: sqlite3 2432** 2433** ^The sqlite3_extended_result_codes() routine enables or disables the 2434** [extended result codes] feature of SQLite. ^The extended result 2435** codes are disabled by default for historical compatibility. 2436*/ 2437int sqlite3_extended_result_codes(sqlite3*, int onoff); 2438 2439/* 2440** CAPI3REF: Last Insert Rowid 2441** METHOD: sqlite3 2442** 2443** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2444** has a unique 64-bit signed 2445** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2446** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2447** names are not also used by explicitly declared columns. ^If 2448** the table has a column of type [INTEGER PRIMARY KEY] then that column 2449** is another alias for the rowid. 2450** 2451** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2452** the most recent successful [INSERT] into a rowid table or [virtual table] 2453** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2454** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2455** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2456** zero. 2457** 2458** As well as being set automatically as rows are inserted into database 2459** tables, the value returned by this function may be set explicitly by 2460** [sqlite3_set_last_insert_rowid()] 2461** 2462** Some virtual table implementations may INSERT rows into rowid tables as 2463** part of committing a transaction (e.g. to flush data accumulated in memory 2464** to disk). In this case subsequent calls to this function return the rowid 2465** associated with these internal INSERT operations, which leads to 2466** unintuitive results. Virtual table implementations that do write to rowid 2467** tables in this way can avoid this problem by restoring the original 2468** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2469** control to the user. 2470** 2471** ^(If an [INSERT] occurs within a trigger then this routine will 2472** return the [rowid] of the inserted row as long as the trigger is 2473** running. Once the trigger program ends, the value returned 2474** by this routine reverts to what it was before the trigger was fired.)^ 2475** 2476** ^An [INSERT] that fails due to a constraint violation is not a 2477** successful [INSERT] and does not change the value returned by this 2478** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2479** and INSERT OR ABORT make no changes to the return value of this 2480** routine when their insertion fails. ^(When INSERT OR REPLACE 2481** encounters a constraint violation, it does not fail. The 2482** INSERT continues to completion after deleting rows that caused 2483** the constraint problem so INSERT OR REPLACE will always change 2484** the return value of this interface.)^ 2485** 2486** ^For the purposes of this routine, an [INSERT] is considered to 2487** be successful even if it is subsequently rolled back. 2488** 2489** This function is accessible to SQL statements via the 2490** [last_insert_rowid() SQL function]. 2491** 2492** If a separate thread performs a new [INSERT] on the same 2493** database connection while the [sqlite3_last_insert_rowid()] 2494** function is running and thus changes the last insert [rowid], 2495** then the value returned by [sqlite3_last_insert_rowid()] is 2496** unpredictable and might not equal either the old or the new 2497** last insert [rowid]. 2498*/ 2499sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2500 2501/* 2502** CAPI3REF: Set the Last Insert Rowid value. 2503** METHOD: sqlite3 2504** 2505** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2506** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2507** without inserting a row into the database. 2508*/ 2509void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2510 2511/* 2512** CAPI3REF: Count The Number Of Rows Modified 2513** METHOD: sqlite3 2514** 2515** ^These functions return the number of rows modified, inserted or 2516** deleted by the most recently completed INSERT, UPDATE or DELETE 2517** statement on the database connection specified by the only parameter. 2518** The two functions are identical except for the type of the return value 2519** and that if the number of rows modified by the most recent INSERT, UPDATE 2520** or DELETE is greater than the maximum value supported by type "int", then 2521** the return value of sqlite3_changes() is undefined. ^Executing any other 2522** type of SQL statement does not modify the value returned by these functions. 2523** 2524** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2525** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2526** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2527** 2528** Changes to a view that are intercepted by 2529** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2530** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2531** DELETE statement run on a view is always zero. Only changes made to real 2532** tables are counted. 2533** 2534** Things are more complicated if the sqlite3_changes() function is 2535** executed while a trigger program is running. This may happen if the 2536** program uses the [changes() SQL function], or if some other callback 2537** function invokes sqlite3_changes() directly. Essentially: 2538** 2539** <ul> 2540** <li> ^(Before entering a trigger program the value returned by 2541** sqlite3_changes() function is saved. After the trigger program 2542** has finished, the original value is restored.)^ 2543** 2544** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2545** statement sets the value returned by sqlite3_changes() 2546** upon completion as normal. Of course, this value will not include 2547** any changes performed by sub-triggers, as the sqlite3_changes() 2548** value will be saved and restored after each sub-trigger has run.)^ 2549** </ul> 2550** 2551** ^This means that if the changes() SQL function (or similar) is used 2552** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2553** returns the value as set when the calling statement began executing. 2554** ^If it is used by the second or subsequent such statement within a trigger 2555** program, the value returned reflects the number of rows modified by the 2556** previous INSERT, UPDATE or DELETE statement within the same trigger. 2557** 2558** If a separate thread makes changes on the same database connection 2559** while [sqlite3_changes()] is running then the value returned 2560** is unpredictable and not meaningful. 2561** 2562** See also: 2563** <ul> 2564** <li> the [sqlite3_total_changes()] interface 2565** <li> the [count_changes pragma] 2566** <li> the [changes() SQL function] 2567** <li> the [data_version pragma] 2568** </ul> 2569*/ 2570int sqlite3_changes(sqlite3*); 2571sqlite3_int64 sqlite3_changes64(sqlite3*); 2572 2573/* 2574** CAPI3REF: Total Number Of Rows Modified 2575** METHOD: sqlite3 2576** 2577** ^These functions return the total number of rows inserted, modified or 2578** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2579** since the database connection was opened, including those executed as 2580** part of trigger programs. The two functions are identical except for the 2581** type of the return value and that if the number of rows modified by the 2582** connection exceeds the maximum value supported by type "int", then 2583** the return value of sqlite3_total_changes() is undefined. ^Executing 2584** any other type of SQL statement does not affect the value returned by 2585** sqlite3_total_changes(). 2586** 2587** ^Changes made as part of [foreign key actions] are included in the 2588** count, but those made as part of REPLACE constraint resolution are 2589** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2590** are not counted. 2591** 2592** The [sqlite3_total_changes(D)] interface only reports the number 2593** of rows that changed due to SQL statement run against database 2594** connection D. Any changes by other database connections are ignored. 2595** To detect changes against a database file from other database 2596** connections use the [PRAGMA data_version] command or the 2597** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2598** 2599** If a separate thread makes changes on the same database connection 2600** while [sqlite3_total_changes()] is running then the value 2601** returned is unpredictable and not meaningful. 2602** 2603** See also: 2604** <ul> 2605** <li> the [sqlite3_changes()] interface 2606** <li> the [count_changes pragma] 2607** <li> the [changes() SQL function] 2608** <li> the [data_version pragma] 2609** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2610** </ul> 2611*/ 2612int sqlite3_total_changes(sqlite3*); 2613sqlite3_int64 sqlite3_total_changes64(sqlite3*); 2614 2615/* 2616** CAPI3REF: Interrupt A Long-Running Query 2617** METHOD: sqlite3 2618** 2619** ^This function causes any pending database operation to abort and 2620** return at its earliest opportunity. This routine is typically 2621** called in response to a user action such as pressing "Cancel" 2622** or Ctrl-C where the user wants a long query operation to halt 2623** immediately. 2624** 2625** ^It is safe to call this routine from a thread different from the 2626** thread that is currently running the database operation. But it 2627** is not safe to call this routine with a [database connection] that 2628** is closed or might close before sqlite3_interrupt() returns. 2629** 2630** ^If an SQL operation is very nearly finished at the time when 2631** sqlite3_interrupt() is called, then it might not have an opportunity 2632** to be interrupted and might continue to completion. 2633** 2634** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2635** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2636** that is inside an explicit transaction, then the entire transaction 2637** will be rolled back automatically. 2638** 2639** ^The sqlite3_interrupt(D) call is in effect until all currently running 2640** SQL statements on [database connection] D complete. ^Any new SQL statements 2641** that are started after the sqlite3_interrupt() call and before the 2642** running statement count reaches zero are interrupted as if they had been 2643** running prior to the sqlite3_interrupt() call. ^New SQL statements 2644** that are started after the running statement count reaches zero are 2645** not effected by the sqlite3_interrupt(). 2646** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2647** SQL statements is a no-op and has no effect on SQL statements 2648** that are started after the sqlite3_interrupt() call returns. 2649*/ 2650void sqlite3_interrupt(sqlite3*); 2651 2652/* 2653** CAPI3REF: Determine If An SQL Statement Is Complete 2654** 2655** These routines are useful during command-line input to determine if the 2656** currently entered text seems to form a complete SQL statement or 2657** if additional input is needed before sending the text into 2658** SQLite for parsing. ^These routines return 1 if the input string 2659** appears to be a complete SQL statement. ^A statement is judged to be 2660** complete if it ends with a semicolon token and is not a prefix of a 2661** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2662** string literals or quoted identifier names or comments are not 2663** independent tokens (they are part of the token in which they are 2664** embedded) and thus do not count as a statement terminator. ^Whitespace 2665** and comments that follow the final semicolon are ignored. 2666** 2667** ^These routines return 0 if the statement is incomplete. ^If a 2668** memory allocation fails, then SQLITE_NOMEM is returned. 2669** 2670** ^These routines do not parse the SQL statements thus 2671** will not detect syntactically incorrect SQL. 2672** 2673** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2674** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2675** automatically by sqlite3_complete16(). If that initialization fails, 2676** then the return value from sqlite3_complete16() will be non-zero 2677** regardless of whether or not the input SQL is complete.)^ 2678** 2679** The input to [sqlite3_complete()] must be a zero-terminated 2680** UTF-8 string. 2681** 2682** The input to [sqlite3_complete16()] must be a zero-terminated 2683** UTF-16 string in native byte order. 2684*/ 2685int sqlite3_complete(const char *sql); 2686int sqlite3_complete16(const void *sql); 2687 2688/* 2689** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2690** KEYWORDS: {busy-handler callback} {busy handler} 2691** METHOD: sqlite3 2692** 2693** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2694** that might be invoked with argument P whenever 2695** an attempt is made to access a database table associated with 2696** [database connection] D when another thread 2697** or process has the table locked. 2698** The sqlite3_busy_handler() interface is used to implement 2699** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2700** 2701** ^If the busy callback is NULL, then [SQLITE_BUSY] 2702** is returned immediately upon encountering the lock. ^If the busy callback 2703** is not NULL, then the callback might be invoked with two arguments. 2704** 2705** ^The first argument to the busy handler is a copy of the void* pointer which 2706** is the third argument to sqlite3_busy_handler(). ^The second argument to 2707** the busy handler callback is the number of times that the busy handler has 2708** been invoked previously for the same locking event. ^If the 2709** busy callback returns 0, then no additional attempts are made to 2710** access the database and [SQLITE_BUSY] is returned 2711** to the application. 2712** ^If the callback returns non-zero, then another attempt 2713** is made to access the database and the cycle repeats. 2714** 2715** The presence of a busy handler does not guarantee that it will be invoked 2716** when there is lock contention. ^If SQLite determines that invoking the busy 2717** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2718** to the application instead of invoking the 2719** busy handler. 2720** Consider a scenario where one process is holding a read lock that 2721** it is trying to promote to a reserved lock and 2722** a second process is holding a reserved lock that it is trying 2723** to promote to an exclusive lock. The first process cannot proceed 2724** because it is blocked by the second and the second process cannot 2725** proceed because it is blocked by the first. If both processes 2726** invoke the busy handlers, neither will make any progress. Therefore, 2727** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2728** will induce the first process to release its read lock and allow 2729** the second process to proceed. 2730** 2731** ^The default busy callback is NULL. 2732** 2733** ^(There can only be a single busy handler defined for each 2734** [database connection]. Setting a new busy handler clears any 2735** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2736** or evaluating [PRAGMA busy_timeout=N] will change the 2737** busy handler and thus clear any previously set busy handler. 2738** 2739** The busy callback should not take any actions which modify the 2740** database connection that invoked the busy handler. In other words, 2741** the busy handler is not reentrant. Any such actions 2742** result in undefined behavior. 2743** 2744** A busy handler must not close the database connection 2745** or [prepared statement] that invoked the busy handler. 2746*/ 2747int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2748 2749/* 2750** CAPI3REF: Set A Busy Timeout 2751** METHOD: sqlite3 2752** 2753** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2754** for a specified amount of time when a table is locked. ^The handler 2755** will sleep multiple times until at least "ms" milliseconds of sleeping 2756** have accumulated. ^After at least "ms" milliseconds of sleeping, 2757** the handler returns 0 which causes [sqlite3_step()] to return 2758** [SQLITE_BUSY]. 2759** 2760** ^Calling this routine with an argument less than or equal to zero 2761** turns off all busy handlers. 2762** 2763** ^(There can only be a single busy handler for a particular 2764** [database connection] at any given moment. If another busy handler 2765** was defined (using [sqlite3_busy_handler()]) prior to calling 2766** this routine, that other busy handler is cleared.)^ 2767** 2768** See also: [PRAGMA busy_timeout] 2769*/ 2770int sqlite3_busy_timeout(sqlite3*, int ms); 2771 2772/* 2773** CAPI3REF: Convenience Routines For Running Queries 2774** METHOD: sqlite3 2775** 2776** This is a legacy interface that is preserved for backwards compatibility. 2777** Use of this interface is not recommended. 2778** 2779** Definition: A <b>result table</b> is memory data structure created by the 2780** [sqlite3_get_table()] interface. A result table records the 2781** complete query results from one or more queries. 2782** 2783** The table conceptually has a number of rows and columns. But 2784** these numbers are not part of the result table itself. These 2785** numbers are obtained separately. Let N be the number of rows 2786** and M be the number of columns. 2787** 2788** A result table is an array of pointers to zero-terminated UTF-8 strings. 2789** There are (N+1)*M elements in the array. The first M pointers point 2790** to zero-terminated strings that contain the names of the columns. 2791** The remaining entries all point to query results. NULL values result 2792** in NULL pointers. All other values are in their UTF-8 zero-terminated 2793** string representation as returned by [sqlite3_column_text()]. 2794** 2795** A result table might consist of one or more memory allocations. 2796** It is not safe to pass a result table directly to [sqlite3_free()]. 2797** A result table should be deallocated using [sqlite3_free_table()]. 2798** 2799** ^(As an example of the result table format, suppose a query result 2800** is as follows: 2801** 2802** <blockquote><pre> 2803** Name | Age 2804** ----------------------- 2805** Alice | 43 2806** Bob | 28 2807** Cindy | 21 2808** </pre></blockquote> 2809** 2810** There are two columns (M==2) and three rows (N==3). Thus the 2811** result table has 8 entries. Suppose the result table is stored 2812** in an array named azResult. Then azResult holds this content: 2813** 2814** <blockquote><pre> 2815** azResult[0] = "Name"; 2816** azResult[1] = "Age"; 2817** azResult[2] = "Alice"; 2818** azResult[3] = "43"; 2819** azResult[4] = "Bob"; 2820** azResult[5] = "28"; 2821** azResult[6] = "Cindy"; 2822** azResult[7] = "21"; 2823** </pre></blockquote>)^ 2824** 2825** ^The sqlite3_get_table() function evaluates one or more 2826** semicolon-separated SQL statements in the zero-terminated UTF-8 2827** string of its 2nd parameter and returns a result table to the 2828** pointer given in its 3rd parameter. 2829** 2830** After the application has finished with the result from sqlite3_get_table(), 2831** it must pass the result table pointer to sqlite3_free_table() in order to 2832** release the memory that was malloced. Because of the way the 2833** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2834** function must not try to call [sqlite3_free()] directly. Only 2835** [sqlite3_free_table()] is able to release the memory properly and safely. 2836** 2837** The sqlite3_get_table() interface is implemented as a wrapper around 2838** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2839** to any internal data structures of SQLite. It uses only the public 2840** interface defined here. As a consequence, errors that occur in the 2841** wrapper layer outside of the internal [sqlite3_exec()] call are not 2842** reflected in subsequent calls to [sqlite3_errcode()] or 2843** [sqlite3_errmsg()]. 2844*/ 2845int sqlite3_get_table( 2846 sqlite3 *db, /* An open database */ 2847 const char *zSql, /* SQL to be evaluated */ 2848 char ***pazResult, /* Results of the query */ 2849 int *pnRow, /* Number of result rows written here */ 2850 int *pnColumn, /* Number of result columns written here */ 2851 char **pzErrmsg /* Error msg written here */ 2852); 2853void sqlite3_free_table(char **result); 2854 2855/* 2856** CAPI3REF: Formatted String Printing Functions 2857** 2858** These routines are work-alikes of the "printf()" family of functions 2859** from the standard C library. 2860** These routines understand most of the common formatting options from 2861** the standard library printf() 2862** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2863** See the [built-in printf()] documentation for details. 2864** 2865** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2866** results into memory obtained from [sqlite3_malloc64()]. 2867** The strings returned by these two routines should be 2868** released by [sqlite3_free()]. ^Both routines return a 2869** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2870** memory to hold the resulting string. 2871** 2872** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2873** the standard C library. The result is written into the 2874** buffer supplied as the second parameter whose size is given by 2875** the first parameter. Note that the order of the 2876** first two parameters is reversed from snprintf().)^ This is an 2877** historical accident that cannot be fixed without breaking 2878** backwards compatibility. ^(Note also that sqlite3_snprintf() 2879** returns a pointer to its buffer instead of the number of 2880** characters actually written into the buffer.)^ We admit that 2881** the number of characters written would be a more useful return 2882** value but we cannot change the implementation of sqlite3_snprintf() 2883** now without breaking compatibility. 2884** 2885** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2886** guarantees that the buffer is always zero-terminated. ^The first 2887** parameter "n" is the total size of the buffer, including space for 2888** the zero terminator. So the longest string that can be completely 2889** written will be n-1 characters. 2890** 2891** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2892** 2893** See also: [built-in printf()], [printf() SQL function] 2894*/ 2895char *sqlite3_mprintf(const char*,...); 2896char *sqlite3_vmprintf(const char*, va_list); 2897char *sqlite3_snprintf(int,char*,const char*, ...); 2898char *sqlite3_vsnprintf(int,char*,const char*, va_list); 2899 2900/* 2901** CAPI3REF: Memory Allocation Subsystem 2902** 2903** The SQLite core uses these three routines for all of its own 2904** internal memory allocation needs. "Core" in the previous sentence 2905** does not include operating-system specific [VFS] implementation. The 2906** Windows VFS uses native malloc() and free() for some operations. 2907** 2908** ^The sqlite3_malloc() routine returns a pointer to a block 2909** of memory at least N bytes in length, where N is the parameter. 2910** ^If sqlite3_malloc() is unable to obtain sufficient free 2911** memory, it returns a NULL pointer. ^If the parameter N to 2912** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2913** a NULL pointer. 2914** 2915** ^The sqlite3_malloc64(N) routine works just like 2916** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2917** of a signed 32-bit integer. 2918** 2919** ^Calling sqlite3_free() with a pointer previously returned 2920** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2921** that it might be reused. ^The sqlite3_free() routine is 2922** a no-op if is called with a NULL pointer. Passing a NULL pointer 2923** to sqlite3_free() is harmless. After being freed, memory 2924** should neither be read nor written. Even reading previously freed 2925** memory might result in a segmentation fault or other severe error. 2926** Memory corruption, a segmentation fault, or other severe error 2927** might result if sqlite3_free() is called with a non-NULL pointer that 2928** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2929** 2930** ^The sqlite3_realloc(X,N) interface attempts to resize a 2931** prior memory allocation X to be at least N bytes. 2932** ^If the X parameter to sqlite3_realloc(X,N) 2933** is a NULL pointer then its behavior is identical to calling 2934** sqlite3_malloc(N). 2935** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2936** negative then the behavior is exactly the same as calling 2937** sqlite3_free(X). 2938** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2939** of at least N bytes in size or NULL if insufficient memory is available. 2940** ^If M is the size of the prior allocation, then min(N,M) bytes 2941** of the prior allocation are copied into the beginning of buffer returned 2942** by sqlite3_realloc(X,N) and the prior allocation is freed. 2943** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2944** prior allocation is not freed. 2945** 2946** ^The sqlite3_realloc64(X,N) interfaces works the same as 2947** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2948** of a 32-bit signed integer. 2949** 2950** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2951** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2952** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2953** ^The value returned by sqlite3_msize(X) might be larger than the number 2954** of bytes requested when X was allocated. ^If X is a NULL pointer then 2955** sqlite3_msize(X) returns zero. If X points to something that is not 2956** the beginning of memory allocation, or if it points to a formerly 2957** valid memory allocation that has now been freed, then the behavior 2958** of sqlite3_msize(X) is undefined and possibly harmful. 2959** 2960** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2961** sqlite3_malloc64(), and sqlite3_realloc64() 2962** is always aligned to at least an 8 byte boundary, or to a 2963** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2964** option is used. 2965** 2966** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2967** must be either NULL or else pointers obtained from a prior 2968** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2969** not yet been released. 2970** 2971** The application must not read or write any part of 2972** a block of memory after it has been released using 2973** [sqlite3_free()] or [sqlite3_realloc()]. 2974*/ 2975void *sqlite3_malloc(int); 2976void *sqlite3_malloc64(sqlite3_uint64); 2977void *sqlite3_realloc(void*, int); 2978void *sqlite3_realloc64(void*, sqlite3_uint64); 2979void sqlite3_free(void*); 2980sqlite3_uint64 sqlite3_msize(void*); 2981 2982/* 2983** CAPI3REF: Memory Allocator Statistics 2984** 2985** SQLite provides these two interfaces for reporting on the status 2986** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 2987** routines, which form the built-in memory allocation subsystem. 2988** 2989** ^The [sqlite3_memory_used()] routine returns the number of bytes 2990** of memory currently outstanding (malloced but not freed). 2991** ^The [sqlite3_memory_highwater()] routine returns the maximum 2992** value of [sqlite3_memory_used()] since the high-water mark 2993** was last reset. ^The values returned by [sqlite3_memory_used()] and 2994** [sqlite3_memory_highwater()] include any overhead 2995** added by SQLite in its implementation of [sqlite3_malloc()], 2996** but not overhead added by the any underlying system library 2997** routines that [sqlite3_malloc()] may call. 2998** 2999** ^The memory high-water mark is reset to the current value of 3000** [sqlite3_memory_used()] if and only if the parameter to 3001** [sqlite3_memory_highwater()] is true. ^The value returned 3002** by [sqlite3_memory_highwater(1)] is the high-water mark 3003** prior to the reset. 3004*/ 3005sqlite3_int64 sqlite3_memory_used(void); 3006sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 3007 3008/* 3009** CAPI3REF: Pseudo-Random Number Generator 3010** 3011** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 3012** select random [ROWID | ROWIDs] when inserting new records into a table that 3013** already uses the largest possible [ROWID]. The PRNG is also used for 3014** the built-in random() and randomblob() SQL functions. This interface allows 3015** applications to access the same PRNG for other purposes. 3016** 3017** ^A call to this routine stores N bytes of randomness into buffer P. 3018** ^The P parameter can be a NULL pointer. 3019** 3020** ^If this routine has not been previously called or if the previous 3021** call had N less than one or a NULL pointer for P, then the PRNG is 3022** seeded using randomness obtained from the xRandomness method of 3023** the default [sqlite3_vfs] object. 3024** ^If the previous call to this routine had an N of 1 or more and a 3025** non-NULL P then the pseudo-randomness is generated 3026** internally and without recourse to the [sqlite3_vfs] xRandomness 3027** method. 3028*/ 3029void sqlite3_randomness(int N, void *P); 3030 3031/* 3032** CAPI3REF: Compile-Time Authorization Callbacks 3033** METHOD: sqlite3 3034** KEYWORDS: {authorizer callback} 3035** 3036** ^This routine registers an authorizer callback with a particular 3037** [database connection], supplied in the first argument. 3038** ^The authorizer callback is invoked as SQL statements are being compiled 3039** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 3040** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 3041** and [sqlite3_prepare16_v3()]. ^At various 3042** points during the compilation process, as logic is being created 3043** to perform various actions, the authorizer callback is invoked to 3044** see if those actions are allowed. ^The authorizer callback should 3045** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 3046** specific action but allow the SQL statement to continue to be 3047** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 3048** rejected with an error. ^If the authorizer callback returns 3049** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 3050** then the [sqlite3_prepare_v2()] or equivalent call that triggered 3051** the authorizer will fail with an error message. 3052** 3053** When the callback returns [SQLITE_OK], that means the operation 3054** requested is ok. ^When the callback returns [SQLITE_DENY], the 3055** [sqlite3_prepare_v2()] or equivalent call that triggered the 3056** authorizer will fail with an error message explaining that 3057** access is denied. 3058** 3059** ^The first parameter to the authorizer callback is a copy of the third 3060** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 3061** to the callback is an integer [SQLITE_COPY | action code] that specifies 3062** the particular action to be authorized. ^The third through sixth parameters 3063** to the callback are either NULL pointers or zero-terminated strings 3064** that contain additional details about the action to be authorized. 3065** Applications must always be prepared to encounter a NULL pointer in any 3066** of the third through the sixth parameters of the authorization callback. 3067** 3068** ^If the action code is [SQLITE_READ] 3069** and the callback returns [SQLITE_IGNORE] then the 3070** [prepared statement] statement is constructed to substitute 3071** a NULL value in place of the table column that would have 3072** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 3073** return can be used to deny an untrusted user access to individual 3074** columns of a table. 3075** ^When a table is referenced by a [SELECT] but no column values are 3076** extracted from that table (for example in a query like 3077** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3078** is invoked once for that table with a column name that is an empty string. 3079** ^If the action code is [SQLITE_DELETE] and the callback returns 3080** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3081** [truncate optimization] is disabled and all rows are deleted individually. 3082** 3083** An authorizer is used when [sqlite3_prepare | preparing] 3084** SQL statements from an untrusted source, to ensure that the SQL statements 3085** do not try to access data they are not allowed to see, or that they do not 3086** try to execute malicious statements that damage the database. For 3087** example, an application may allow a user to enter arbitrary 3088** SQL queries for evaluation by a database. But the application does 3089** not want the user to be able to make arbitrary changes to the 3090** database. An authorizer could then be put in place while the 3091** user-entered SQL is being [sqlite3_prepare | prepared] that 3092** disallows everything except [SELECT] statements. 3093** 3094** Applications that need to process SQL from untrusted sources 3095** might also consider lowering resource limits using [sqlite3_limit()] 3096** and limiting database size using the [max_page_count] [PRAGMA] 3097** in addition to using an authorizer. 3098** 3099** ^(Only a single authorizer can be in place on a database connection 3100** at a time. Each call to sqlite3_set_authorizer overrides the 3101** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3102** The authorizer is disabled by default. 3103** 3104** The authorizer callback must not do anything that will modify 3105** the database connection that invoked the authorizer callback. 3106** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3107** database connections for the meaning of "modify" in this paragraph. 3108** 3109** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3110** statement might be re-prepared during [sqlite3_step()] due to a 3111** schema change. Hence, the application should ensure that the 3112** correct authorizer callback remains in place during the [sqlite3_step()]. 3113** 3114** ^Note that the authorizer callback is invoked only during 3115** [sqlite3_prepare()] or its variants. Authorization is not 3116** performed during statement evaluation in [sqlite3_step()], unless 3117** as stated in the previous paragraph, sqlite3_step() invokes 3118** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3119*/ 3120int sqlite3_set_authorizer( 3121 sqlite3*, 3122 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3123 void *pUserData 3124); 3125 3126/* 3127** CAPI3REF: Authorizer Return Codes 3128** 3129** The [sqlite3_set_authorizer | authorizer callback function] must 3130** return either [SQLITE_OK] or one of these two constants in order 3131** to signal SQLite whether or not the action is permitted. See the 3132** [sqlite3_set_authorizer | authorizer documentation] for additional 3133** information. 3134** 3135** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3136** returned from the [sqlite3_vtab_on_conflict()] interface. 3137*/ 3138#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3139#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3140 3141/* 3142** CAPI3REF: Authorizer Action Codes 3143** 3144** The [sqlite3_set_authorizer()] interface registers a callback function 3145** that is invoked to authorize certain SQL statement actions. The 3146** second parameter to the callback is an integer code that specifies 3147** what action is being authorized. These are the integer action codes that 3148** the authorizer callback may be passed. 3149** 3150** These action code values signify what kind of operation is to be 3151** authorized. The 3rd and 4th parameters to the authorization 3152** callback function will be parameters or NULL depending on which of these 3153** codes is used as the second parameter. ^(The 5th parameter to the 3154** authorizer callback is the name of the database ("main", "temp", 3155** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3156** is the name of the inner-most trigger or view that is responsible for 3157** the access attempt or NULL if this access attempt is directly from 3158** top-level SQL code. 3159*/ 3160/******************************************* 3rd ************ 4th ***********/ 3161#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3162#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3163#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3164#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3165#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3166#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3167#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3168#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3169#define SQLITE_DELETE 9 /* Table Name NULL */ 3170#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3171#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3172#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3173#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3174#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3175#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3176#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3177#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3178#define SQLITE_INSERT 18 /* Table Name NULL */ 3179#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3180#define SQLITE_READ 20 /* Table Name Column Name */ 3181#define SQLITE_SELECT 21 /* NULL NULL */ 3182#define SQLITE_TRANSACTION 22 /* Operation NULL */ 3183#define SQLITE_UPDATE 23 /* Table Name Column Name */ 3184#define SQLITE_ATTACH 24 /* Filename NULL */ 3185#define SQLITE_DETACH 25 /* Database Name NULL */ 3186#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3187#define SQLITE_REINDEX 27 /* Index Name NULL */ 3188#define SQLITE_ANALYZE 28 /* Table Name NULL */ 3189#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3190#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3191#define SQLITE_FUNCTION 31 /* NULL Function Name */ 3192#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3193#define SQLITE_COPY 0 /* No longer used */ 3194#define SQLITE_RECURSIVE 33 /* NULL NULL */ 3195 3196/* 3197** CAPI3REF: Tracing And Profiling Functions 3198** METHOD: sqlite3 3199** 3200** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3201** instead of the routines described here. 3202** 3203** These routines register callback functions that can be used for 3204** tracing and profiling the execution of SQL statements. 3205** 3206** ^The callback function registered by sqlite3_trace() is invoked at 3207** various times when an SQL statement is being run by [sqlite3_step()]. 3208** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3209** SQL statement text as the statement first begins executing. 3210** ^(Additional sqlite3_trace() callbacks might occur 3211** as each triggered subprogram is entered. The callbacks for triggers 3212** contain a UTF-8 SQL comment that identifies the trigger.)^ 3213** 3214** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3215** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3216** 3217** ^The callback function registered by sqlite3_profile() is invoked 3218** as each SQL statement finishes. ^The profile callback contains 3219** the original statement text and an estimate of wall-clock time 3220** of how long that statement took to run. ^The profile callback 3221** time is in units of nanoseconds, however the current implementation 3222** is only capable of millisecond resolution so the six least significant 3223** digits in the time are meaningless. Future versions of SQLite 3224** might provide greater resolution on the profiler callback. Invoking 3225** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3226** profile callback. 3227*/ 3228SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3229 void(*xTrace)(void*,const char*), void*); 3230SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3231 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3232 3233/* 3234** CAPI3REF: SQL Trace Event Codes 3235** KEYWORDS: SQLITE_TRACE 3236** 3237** These constants identify classes of events that can be monitored 3238** using the [sqlite3_trace_v2()] tracing logic. The M argument 3239** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3240** the following constants. ^The first argument to the trace callback 3241** is one of the following constants. 3242** 3243** New tracing constants may be added in future releases. 3244** 3245** ^A trace callback has four arguments: xCallback(T,C,P,X). 3246** ^The T argument is one of the integer type codes above. 3247** ^The C argument is a copy of the context pointer passed in as the 3248** fourth argument to [sqlite3_trace_v2()]. 3249** The P and X arguments are pointers whose meanings depend on T. 3250** 3251** <dl> 3252** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3253** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3254** first begins running and possibly at other times during the 3255** execution of the prepared statement, such as at the start of each 3256** trigger subprogram. ^The P argument is a pointer to the 3257** [prepared statement]. ^The X argument is a pointer to a string which 3258** is the unexpanded SQL text of the prepared statement or an SQL comment 3259** that indicates the invocation of a trigger. ^The callback can compute 3260** the same text that would have been returned by the legacy [sqlite3_trace()] 3261** interface by using the X argument when X begins with "--" and invoking 3262** [sqlite3_expanded_sql(P)] otherwise. 3263** 3264** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3265** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3266** information as is provided by the [sqlite3_profile()] callback. 3267** ^The P argument is a pointer to the [prepared statement] and the 3268** X argument points to a 64-bit integer which is the estimated of 3269** the number of nanosecond that the prepared statement took to run. 3270** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3271** 3272** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3273** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3274** statement generates a single row of result. 3275** ^The P argument is a pointer to the [prepared statement] and the 3276** X argument is unused. 3277** 3278** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3279** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3280** connection closes. 3281** ^The P argument is a pointer to the [database connection] object 3282** and the X argument is unused. 3283** </dl> 3284*/ 3285#define SQLITE_TRACE_STMT 0x01 3286#define SQLITE_TRACE_PROFILE 0x02 3287#define SQLITE_TRACE_ROW 0x04 3288#define SQLITE_TRACE_CLOSE 0x08 3289 3290/* 3291** CAPI3REF: SQL Trace Hook 3292** METHOD: sqlite3 3293** 3294** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3295** function X against [database connection] D, using property mask M 3296** and context pointer P. ^If the X callback is 3297** NULL or if the M mask is zero, then tracing is disabled. The 3298** M argument should be the bitwise OR-ed combination of 3299** zero or more [SQLITE_TRACE] constants. 3300** 3301** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides 3302** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). 3303** 3304** ^The X callback is invoked whenever any of the events identified by 3305** mask M occur. ^The integer return value from the callback is currently 3306** ignored, though this may change in future releases. Callback 3307** implementations should return zero to ensure future compatibility. 3308** 3309** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3310** ^The T argument is one of the [SQLITE_TRACE] 3311** constants to indicate why the callback was invoked. 3312** ^The C argument is a copy of the context pointer. 3313** The P and X arguments are pointers whose meanings depend on T. 3314** 3315** The sqlite3_trace_v2() interface is intended to replace the legacy 3316** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3317** are deprecated. 3318*/ 3319int sqlite3_trace_v2( 3320 sqlite3*, 3321 unsigned uMask, 3322 int(*xCallback)(unsigned,void*,void*,void*), 3323 void *pCtx 3324); 3325 3326/* 3327** CAPI3REF: Query Progress Callbacks 3328** METHOD: sqlite3 3329** 3330** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3331** function X to be invoked periodically during long running calls to 3332** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 3333** database connection D. An example use for this 3334** interface is to keep a GUI updated during a large query. 3335** 3336** ^The parameter P is passed through as the only parameter to the 3337** callback function X. ^The parameter N is the approximate number of 3338** [virtual machine instructions] that are evaluated between successive 3339** invocations of the callback X. ^If N is less than one then the progress 3340** handler is disabled. 3341** 3342** ^Only a single progress handler may be defined at one time per 3343** [database connection]; setting a new progress handler cancels the 3344** old one. ^Setting parameter X to NULL disables the progress handler. 3345** ^The progress handler is also disabled by setting N to a value less 3346** than 1. 3347** 3348** ^If the progress callback returns non-zero, the operation is 3349** interrupted. This feature can be used to implement a 3350** "Cancel" button on a GUI progress dialog box. 3351** 3352** The progress handler callback must not do anything that will modify 3353** the database connection that invoked the progress handler. 3354** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3355** database connections for the meaning of "modify" in this paragraph. 3356** 3357*/ 3358void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3359 3360/* 3361** CAPI3REF: Opening A New Database Connection 3362** CONSTRUCTOR: sqlite3 3363** 3364** ^These routines open an SQLite database file as specified by the 3365** filename argument. ^The filename argument is interpreted as UTF-8 for 3366** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3367** order for sqlite3_open16(). ^(A [database connection] handle is usually 3368** returned in *ppDb, even if an error occurs. The only exception is that 3369** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3370** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3371** object.)^ ^(If the database is opened (and/or created) successfully, then 3372** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3373** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3374** an English language description of the error following a failure of any 3375** of the sqlite3_open() routines. 3376** 3377** ^The default encoding will be UTF-8 for databases created using 3378** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3379** created using sqlite3_open16() will be UTF-16 in the native byte order. 3380** 3381** Whether or not an error occurs when it is opened, resources 3382** associated with the [database connection] handle should be released by 3383** passing it to [sqlite3_close()] when it is no longer required. 3384** 3385** The sqlite3_open_v2() interface works like sqlite3_open() 3386** except that it accepts two additional parameters for additional control 3387** over the new database connection. ^(The flags parameter to 3388** sqlite3_open_v2() must include, at a minimum, one of the following 3389** three flag combinations:)^ 3390** 3391** <dl> 3392** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3393** <dd>The database is opened in read-only mode. If the database does not 3394** already exist, an error is returned.</dd>)^ 3395** 3396** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3397** <dd>The database is opened for reading and writing if possible, or reading 3398** only if the file is write protected by the operating system. In either 3399** case the database must already exist, otherwise an error is returned.</dd>)^ 3400** 3401** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3402** <dd>The database is opened for reading and writing, and is created if 3403** it does not already exist. This is the behavior that is always used for 3404** sqlite3_open() and sqlite3_open16().</dd>)^ 3405** </dl> 3406** 3407** In addition to the required flags, the following optional flags are 3408** also supported: 3409** 3410** <dl> 3411** ^(<dt>[SQLITE_OPEN_URI]</dt> 3412** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3413** 3414** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3415** <dd>The database will be opened as an in-memory database. The database 3416** is named by the "filename" argument for the purposes of cache-sharing, 3417** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3418** </dd>)^ 3419** 3420** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3421** <dd>The new database connection will use the "multi-thread" 3422** [threading mode].)^ This means that separate threads are allowed 3423** to use SQLite at the same time, as long as each thread is using 3424** a different [database connection]. 3425** 3426** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3427** <dd>The new database connection will use the "serialized" 3428** [threading mode].)^ This means the multiple threads can safely 3429** attempt to use the same database connection at the same time. 3430** (Mutexes will block any actual concurrency, but in this mode 3431** there is no harm in trying.) 3432** 3433** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3434** <dd>The database is opened [shared cache] enabled, overriding 3435** the default shared cache setting provided by 3436** [sqlite3_enable_shared_cache()].)^ 3437** The [use of shared cache mode is discouraged] and hence shared cache 3438** capabilities may be omitted from many builds of SQLite. In such cases, 3439** this option is a no-op. 3440** 3441** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3442** <dd>The database is opened [shared cache] disabled, overriding 3443** the default shared cache setting provided by 3444** [sqlite3_enable_shared_cache()].)^ 3445** 3446** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt> 3447** <dd>The database connection comes up in "extended result code mode". 3448** In other words, the database behaves has if 3449** [sqlite3_extended_result_codes(db,1)] where called on the database 3450** connection as soon as the connection is created. In addition to setting 3451** the extended result code mode, this flag also causes [sqlite3_open_v2()] 3452** to return an extended result code.</dd> 3453** 3454** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3455** <dd>The database filename is not allowed to contain a symbolic link</dd> 3456** </dl>)^ 3457** 3458** If the 3rd parameter to sqlite3_open_v2() is not one of the 3459** required combinations shown above optionally combined with other 3460** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3461** then the behavior is undefined. Historic versions of SQLite 3462** have silently ignored surplus bits in the flags parameter to 3463** sqlite3_open_v2(), however that behavior might not be carried through 3464** into future versions of SQLite and so applications should not rely 3465** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op 3466** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause 3467** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE 3468** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not 3469** by sqlite3_open_v2(). 3470** 3471** ^The fourth parameter to sqlite3_open_v2() is the name of the 3472** [sqlite3_vfs] object that defines the operating system interface that 3473** the new database connection should use. ^If the fourth parameter is 3474** a NULL pointer then the default [sqlite3_vfs] object is used. 3475** 3476** ^If the filename is ":memory:", then a private, temporary in-memory database 3477** is created for the connection. ^This in-memory database will vanish when 3478** the database connection is closed. Future versions of SQLite might 3479** make use of additional special filenames that begin with the ":" character. 3480** It is recommended that when a database filename actually does begin with 3481** a ":" character you should prefix the filename with a pathname such as 3482** "./" to avoid ambiguity. 3483** 3484** ^If the filename is an empty string, then a private, temporary 3485** on-disk database will be created. ^This private database will be 3486** automatically deleted as soon as the database connection is closed. 3487** 3488** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3489** 3490** ^If [URI filename] interpretation is enabled, and the filename argument 3491** begins with "file:", then the filename is interpreted as a URI. ^URI 3492** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3493** set in the third argument to sqlite3_open_v2(), or if it has 3494** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3495** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3496** URI filename interpretation is turned off 3497** by default, but future releases of SQLite might enable URI filename 3498** interpretation by default. See "[URI filenames]" for additional 3499** information. 3500** 3501** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3502** authority, then it must be either an empty string or the string 3503** "localhost". ^If the authority is not an empty string or "localhost", an 3504** error is returned to the caller. ^The fragment component of a URI, if 3505** present, is ignored. 3506** 3507** ^SQLite uses the path component of the URI as the name of the disk file 3508** which contains the database. ^If the path begins with a '/' character, 3509** then it is interpreted as an absolute path. ^If the path does not begin 3510** with a '/' (meaning that the authority section is omitted from the URI) 3511** then the path is interpreted as a relative path. 3512** ^(On windows, the first component of an absolute path 3513** is a drive specification (e.g. "C:").)^ 3514** 3515** [[core URI query parameters]] 3516** The query component of a URI may contain parameters that are interpreted 3517** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3518** SQLite and its built-in [VFSes] interpret the 3519** following query parameters: 3520** 3521** <ul> 3522** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3523** a VFS object that provides the operating system interface that should 3524** be used to access the database file on disk. ^If this option is set to 3525** an empty string the default VFS object is used. ^Specifying an unknown 3526** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3527** present, then the VFS specified by the option takes precedence over 3528** the value passed as the fourth parameter to sqlite3_open_v2(). 3529** 3530** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3531** "rwc", or "memory". Attempting to set it to any other value is 3532** an error)^. 3533** ^If "ro" is specified, then the database is opened for read-only 3534** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3535** third argument to sqlite3_open_v2(). ^If the mode option is set to 3536** "rw", then the database is opened for read-write (but not create) 3537** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3538** been set. ^Value "rwc" is equivalent to setting both 3539** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3540** set to "memory" then a pure [in-memory database] that never reads 3541** or writes from disk is used. ^It is an error to specify a value for 3542** the mode parameter that is less restrictive than that specified by 3543** the flags passed in the third parameter to sqlite3_open_v2(). 3544** 3545** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3546** "private". ^Setting it to "shared" is equivalent to setting the 3547** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3548** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3549** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3550** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3551** a URI filename, its value overrides any behavior requested by setting 3552** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3553** 3554** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3555** [powersafe overwrite] property does or does not apply to the 3556** storage media on which the database file resides. 3557** 3558** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3559** which if set disables file locking in rollback journal modes. This 3560** is useful for accessing a database on a filesystem that does not 3561** support locking. Caution: Database corruption might result if two 3562** or more processes write to the same database and any one of those 3563** processes uses nolock=1. 3564** 3565** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3566** parameter that indicates that the database file is stored on 3567** read-only media. ^When immutable is set, SQLite assumes that the 3568** database file cannot be changed, even by a process with higher 3569** privilege, and so the database is opened read-only and all locking 3570** and change detection is disabled. Caution: Setting the immutable 3571** property on a database file that does in fact change can result 3572** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3573** See also: [SQLITE_IOCAP_IMMUTABLE]. 3574** 3575** </ul> 3576** 3577** ^Specifying an unknown parameter in the query component of a URI is not an 3578** error. Future versions of SQLite might understand additional query 3579** parameters. See "[query parameters with special meaning to SQLite]" for 3580** additional information. 3581** 3582** [[URI filename examples]] <h3>URI filename examples</h3> 3583** 3584** <table border="1" align=center cellpadding=5> 3585** <tr><th> URI filenames <th> Results 3586** <tr><td> file:data.db <td> 3587** Open the file "data.db" in the current directory. 3588** <tr><td> file:/home/fred/data.db<br> 3589** file:///home/fred/data.db <br> 3590** file://localhost/home/fred/data.db <br> <td> 3591** Open the database file "/home/fred/data.db". 3592** <tr><td> file://darkstar/home/fred/data.db <td> 3593** An error. "darkstar" is not a recognized authority. 3594** <tr><td style="white-space:nowrap"> 3595** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3596** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3597** C:. Note that the %20 escaping in this example is not strictly 3598** necessary - space characters can be used literally 3599** in URI filenames. 3600** <tr><td> file:data.db?mode=ro&cache=private <td> 3601** Open file "data.db" in the current directory for read-only access. 3602** Regardless of whether or not shared-cache mode is enabled by 3603** default, use a private cache. 3604** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3605** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3606** that uses dot-files in place of posix advisory locking. 3607** <tr><td> file:data.db?mode=readonly <td> 3608** An error. "readonly" is not a valid option for the "mode" parameter. 3609** Use "ro" instead: "file:data.db?mode=ro". 3610** </table> 3611** 3612** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3613** query components of a URI. A hexadecimal escape sequence consists of a 3614** percent sign - "%" - followed by exactly two hexadecimal digits 3615** specifying an octet value. ^Before the path or query components of a 3616** URI filename are interpreted, they are encoded using UTF-8 and all 3617** hexadecimal escape sequences replaced by a single byte containing the 3618** corresponding octet. If this process generates an invalid UTF-8 encoding, 3619** the results are undefined. 3620** 3621** <b>Note to Windows users:</b> The encoding used for the filename argument 3622** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3623** codepage is currently defined. Filenames containing international 3624** characters must be converted to UTF-8 prior to passing them into 3625** sqlite3_open() or sqlite3_open_v2(). 3626** 3627** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3628** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3629** features that require the use of temporary files may fail. 3630** 3631** See also: [sqlite3_temp_directory] 3632*/ 3633int sqlite3_open( 3634 const char *filename, /* Database filename (UTF-8) */ 3635 sqlite3 **ppDb /* OUT: SQLite db handle */ 3636); 3637int sqlite3_open16( 3638 const void *filename, /* Database filename (UTF-16) */ 3639 sqlite3 **ppDb /* OUT: SQLite db handle */ 3640); 3641int sqlite3_open_v2( 3642 const char *filename, /* Database filename (UTF-8) */ 3643 sqlite3 **ppDb, /* OUT: SQLite db handle */ 3644 int flags, /* Flags */ 3645 const char *zVfs /* Name of VFS module to use */ 3646); 3647 3648/* 3649** CAPI3REF: Obtain Values For URI Parameters 3650** 3651** These are utility routines, useful to [VFS|custom VFS implementations], 3652** that check if a database file was a URI that contained a specific query 3653** parameter, and if so obtains the value of that query parameter. 3654** 3655** The first parameter to these interfaces (hereafter referred to 3656** as F) must be one of: 3657** <ul> 3658** <li> A database filename pointer created by the SQLite core and 3659** passed into the xOpen() method of a VFS implemention, or 3660** <li> A filename obtained from [sqlite3_db_filename()], or 3661** <li> A new filename constructed using [sqlite3_create_filename()]. 3662** </ul> 3663** If the F parameter is not one of the above, then the behavior is 3664** undefined and probably undesirable. Older versions of SQLite were 3665** more tolerant of invalid F parameters than newer versions. 3666** 3667** If F is a suitable filename (as described in the previous paragraph) 3668** and if P is the name of the query parameter, then 3669** sqlite3_uri_parameter(F,P) returns the value of the P 3670** parameter if it exists or a NULL pointer if P does not appear as a 3671** query parameter on F. If P is a query parameter of F and it 3672** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3673** a pointer to an empty string. 3674** 3675** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3676** parameter and returns true (1) or false (0) according to the value 3677** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3678** value of query parameter P is one of "yes", "true", or "on" in any 3679** case or if the value begins with a non-zero number. The 3680** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3681** query parameter P is one of "no", "false", or "off" in any case or 3682** if the value begins with a numeric zero. If P is not a query 3683** parameter on F or if the value of P does not match any of the 3684** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3685** 3686** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3687** 64-bit signed integer and returns that integer, or D if P does not 3688** exist. If the value of P is something other than an integer, then 3689** zero is returned. 3690** 3691** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3692** the value) of the N-th query parameter for filename F, or a NULL 3693** pointer if N is less than zero or greater than the number of query 3694** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3695** the name of the first query parameter, 1 for the second parameter, and 3696** so forth. 3697** 3698** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3699** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3700** is not a database file pathname pointer that the SQLite core passed 3701** into the xOpen VFS method, then the behavior of this routine is undefined 3702** and probably undesirable. 3703** 3704** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3705** parameter can also be the name of a rollback journal file or WAL file 3706** in addition to the main database file. Prior to version 3.31.0, these 3707** routines would only work if F was the name of the main database file. 3708** When the F parameter is the name of the rollback journal or WAL file, 3709** it has access to all the same query parameters as were found on the 3710** main database file. 3711** 3712** See the [URI filename] documentation for additional information. 3713*/ 3714const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); 3715int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); 3716sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); 3717const char *sqlite3_uri_key(const char *zFilename, int N); 3718 3719/* 3720** CAPI3REF: Translate filenames 3721** 3722** These routines are available to [VFS|custom VFS implementations] for 3723** translating filenames between the main database file, the journal file, 3724** and the WAL file. 3725** 3726** If F is the name of an sqlite database file, journal file, or WAL file 3727** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3728** returns the name of the corresponding database file. 3729** 3730** If F is the name of an sqlite database file, journal file, or WAL file 3731** passed by the SQLite core into the VFS, or if F is a database filename 3732** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3733** returns the name of the corresponding rollback journal file. 3734** 3735** If F is the name of an sqlite database file, journal file, or WAL file 3736** that was passed by the SQLite core into the VFS, or if F is a database 3737** filename obtained from [sqlite3_db_filename()], then 3738** sqlite3_filename_wal(F) returns the name of the corresponding 3739** WAL file. 3740** 3741** In all of the above, if F is not the name of a database, journal or WAL 3742** filename passed into the VFS from the SQLite core and F is not the 3743** return value from [sqlite3_db_filename()], then the result is 3744** undefined and is likely a memory access violation. 3745*/ 3746const char *sqlite3_filename_database(const char*); 3747const char *sqlite3_filename_journal(const char*); 3748const char *sqlite3_filename_wal(const char*); 3749 3750/* 3751** CAPI3REF: Database File Corresponding To A Journal 3752** 3753** ^If X is the name of a rollback or WAL-mode journal file that is 3754** passed into the xOpen method of [sqlite3_vfs], then 3755** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 3756** object that represents the main database file. 3757** 3758** This routine is intended for use in custom [VFS] implementations 3759** only. It is not a general-purpose interface. 3760** The argument sqlite3_file_object(X) must be a filename pointer that 3761** has been passed into [sqlite3_vfs].xOpen method where the 3762** flags parameter to xOpen contains one of the bits 3763** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 3764** of this routine results in undefined and probably undesirable 3765** behavior. 3766*/ 3767sqlite3_file *sqlite3_database_file_object(const char*); 3768 3769/* 3770** CAPI3REF: Create and Destroy VFS Filenames 3771** 3772** These interfces are provided for use by [VFS shim] implementations and 3773** are not useful outside of that context. 3774** 3775** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 3776** database filename D with corresponding journal file J and WAL file W and 3777** with N URI parameters key/values pairs in the array P. The result from 3778** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 3779** is safe to pass to routines like: 3780** <ul> 3781** <li> [sqlite3_uri_parameter()], 3782** <li> [sqlite3_uri_boolean()], 3783** <li> [sqlite3_uri_int64()], 3784** <li> [sqlite3_uri_key()], 3785** <li> [sqlite3_filename_database()], 3786** <li> [sqlite3_filename_journal()], or 3787** <li> [sqlite3_filename_wal()]. 3788** </ul> 3789** If a memory allocation error occurs, sqlite3_create_filename() might 3790** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 3791** must be released by a corresponding call to sqlite3_free_filename(Y). 3792** 3793** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 3794** of 2*N pointers to strings. Each pair of pointers in this array corresponds 3795** to a key and value for a query parameter. The P parameter may be a NULL 3796** pointer if N is zero. None of the 2*N pointers in the P array may be 3797** NULL pointers and key pointers should not be empty strings. 3798** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 3799** be NULL pointers, though they can be empty strings. 3800** 3801** The sqlite3_free_filename(Y) routine releases a memory allocation 3802** previously obtained from sqlite3_create_filename(). Invoking 3803** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 3804** 3805** If the Y parameter to sqlite3_free_filename(Y) is anything other 3806** than a NULL pointer or a pointer previously acquired from 3807** sqlite3_create_filename(), then bad things such as heap 3808** corruption or segfaults may occur. The value Y should not be 3809** used again after sqlite3_free_filename(Y) has been called. This means 3810** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 3811** then the corresponding [sqlite3_module.xClose() method should also be 3812** invoked prior to calling sqlite3_free_filename(Y). 3813*/ 3814char *sqlite3_create_filename( 3815 const char *zDatabase, 3816 const char *zJournal, 3817 const char *zWal, 3818 int nParam, 3819 const char **azParam 3820); 3821void sqlite3_free_filename(char*); 3822 3823/* 3824** CAPI3REF: Error Codes And Messages 3825** METHOD: sqlite3 3826** 3827** ^If the most recent sqlite3_* API call associated with 3828** [database connection] D failed, then the sqlite3_errcode(D) interface 3829** returns the numeric [result code] or [extended result code] for that 3830** API call. 3831** ^The sqlite3_extended_errcode() 3832** interface is the same except that it always returns the 3833** [extended result code] even when extended result codes are 3834** disabled. 3835** 3836** The values returned by sqlite3_errcode() and/or 3837** sqlite3_extended_errcode() might change with each API call. 3838** Except, there are some interfaces that are guaranteed to never 3839** change the value of the error code. The error-code preserving 3840** interfaces include the following: 3841** 3842** <ul> 3843** <li> sqlite3_errcode() 3844** <li> sqlite3_extended_errcode() 3845** <li> sqlite3_errmsg() 3846** <li> sqlite3_errmsg16() 3847** <li> sqlite3_error_offset() 3848** </ul> 3849** 3850** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3851** text that describes the error, as either UTF-8 or UTF-16 respectively. 3852** ^(Memory to hold the error message string is managed internally. 3853** The application does not need to worry about freeing the result. 3854** However, the error string might be overwritten or deallocated by 3855** subsequent calls to other SQLite interface functions.)^ 3856** 3857** ^The sqlite3_errstr() interface returns the English-language text 3858** that describes the [result code], as UTF-8. 3859** ^(Memory to hold the error message string is managed internally 3860** and must not be freed by the application)^. 3861** 3862** ^If the most recent error references a specific token in the input 3863** SQL, the sqlite3_error_offset() interface returns the byte offset 3864** of the start of that token. ^The byte offset returned by 3865** sqlite3_error_offset() assumes that the input SQL is UTF8. 3866** ^If the most recent error does not reference a specific token in the input 3867** SQL, then the sqlite3_error_offset() function returns -1. 3868** 3869** When the serialized [threading mode] is in use, it might be the 3870** case that a second error occurs on a separate thread in between 3871** the time of the first error and the call to these interfaces. 3872** When that happens, the second error will be reported since these 3873** interfaces always report the most recent result. To avoid 3874** this, each thread can obtain exclusive use of the [database connection] D 3875** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3876** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3877** all calls to the interfaces listed here are completed. 3878** 3879** If an interface fails with SQLITE_MISUSE, that means the interface 3880** was invoked incorrectly by the application. In that case, the 3881** error code and message may or may not be set. 3882*/ 3883int sqlite3_errcode(sqlite3 *db); 3884int sqlite3_extended_errcode(sqlite3 *db); 3885const char *sqlite3_errmsg(sqlite3*); 3886const void *sqlite3_errmsg16(sqlite3*); 3887const char *sqlite3_errstr(int); 3888int sqlite3_error_offset(sqlite3 *db); 3889 3890/* 3891** CAPI3REF: Prepared Statement Object 3892** KEYWORDS: {prepared statement} {prepared statements} 3893** 3894** An instance of this object represents a single SQL statement that 3895** has been compiled into binary form and is ready to be evaluated. 3896** 3897** Think of each SQL statement as a separate computer program. The 3898** original SQL text is source code. A prepared statement object 3899** is the compiled object code. All SQL must be converted into a 3900** prepared statement before it can be run. 3901** 3902** The life-cycle of a prepared statement object usually goes like this: 3903** 3904** <ol> 3905** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3906** <li> Bind values to [parameters] using the sqlite3_bind_*() 3907** interfaces. 3908** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3909** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3910** to step 2. Do this zero or more times. 3911** <li> Destroy the object using [sqlite3_finalize()]. 3912** </ol> 3913*/ 3914typedef struct sqlite3_stmt sqlite3_stmt; 3915 3916/* 3917** CAPI3REF: Run-time Limits 3918** METHOD: sqlite3 3919** 3920** ^(This interface allows the size of various constructs to be limited 3921** on a connection by connection basis. The first parameter is the 3922** [database connection] whose limit is to be set or queried. The 3923** second parameter is one of the [limit categories] that define a 3924** class of constructs to be size limited. The third parameter is the 3925** new limit for that construct.)^ 3926** 3927** ^If the new limit is a negative number, the limit is unchanged. 3928** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3929** [limits | hard upper bound] 3930** set at compile-time by a C preprocessor macro called 3931** [limits | SQLITE_MAX_<i>NAME</i>]. 3932** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3933** ^Attempts to increase a limit above its hard upper bound are 3934** silently truncated to the hard upper bound. 3935** 3936** ^Regardless of whether or not the limit was changed, the 3937** [sqlite3_limit()] interface returns the prior value of the limit. 3938** ^Hence, to find the current value of a limit without changing it, 3939** simply invoke this interface with the third parameter set to -1. 3940** 3941** Run-time limits are intended for use in applications that manage 3942** both their own internal database and also databases that are controlled 3943** by untrusted external sources. An example application might be a 3944** web browser that has its own databases for storing history and 3945** separate databases controlled by JavaScript applications downloaded 3946** off the Internet. The internal databases can be given the 3947** large, default limits. Databases managed by external sources can 3948** be given much smaller limits designed to prevent a denial of service 3949** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3950** interface to further control untrusted SQL. The size of the database 3951** created by an untrusted script can be contained using the 3952** [max_page_count] [PRAGMA]. 3953** 3954** New run-time limit categories may be added in future releases. 3955*/ 3956int sqlite3_limit(sqlite3*, int id, int newVal); 3957 3958/* 3959** CAPI3REF: Run-Time Limit Categories 3960** KEYWORDS: {limit category} {*limit categories} 3961** 3962** These constants define various performance limits 3963** that can be lowered at run-time using [sqlite3_limit()]. 3964** The synopsis of the meanings of the various limits is shown below. 3965** Additional information is available at [limits | Limits in SQLite]. 3966** 3967** <dl> 3968** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3969** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3970** 3971** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3972** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3973** 3974** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3975** <dd>The maximum number of columns in a table definition or in the 3976** result set of a [SELECT] or the maximum number of columns in an index 3977** or in an ORDER BY or GROUP BY clause.</dd>)^ 3978** 3979** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 3980** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 3981** 3982** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 3983** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 3984** 3985** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 3986** <dd>The maximum number of instructions in a virtual machine program 3987** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 3988** the equivalent tries to allocate space for more than this many opcodes 3989** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 3990** 3991** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 3992** <dd>The maximum number of arguments on a function.</dd>)^ 3993** 3994** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 3995** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 3996** 3997** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 3998** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 3999** <dd>The maximum length of the pattern argument to the [LIKE] or 4000** [GLOB] operators.</dd>)^ 4001** 4002** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 4003** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 4004** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 4005** 4006** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 4007** <dd>The maximum depth of recursion for triggers.</dd>)^ 4008** 4009** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 4010** <dd>The maximum number of auxiliary worker threads that a single 4011** [prepared statement] may start.</dd>)^ 4012** </dl> 4013*/ 4014#define SQLITE_LIMIT_LENGTH 0 4015#define SQLITE_LIMIT_SQL_LENGTH 1 4016#define SQLITE_LIMIT_COLUMN 2 4017#define SQLITE_LIMIT_EXPR_DEPTH 3 4018#define SQLITE_LIMIT_COMPOUND_SELECT 4 4019#define SQLITE_LIMIT_VDBE_OP 5 4020#define SQLITE_LIMIT_FUNCTION_ARG 6 4021#define SQLITE_LIMIT_ATTACHED 7 4022#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 4023#define SQLITE_LIMIT_VARIABLE_NUMBER 9 4024#define SQLITE_LIMIT_TRIGGER_DEPTH 10 4025#define SQLITE_LIMIT_WORKER_THREADS 11 4026 4027/* 4028** CAPI3REF: Prepare Flags 4029** 4030** These constants define various flags that can be passed into 4031** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 4032** [sqlite3_prepare16_v3()] interfaces. 4033** 4034** New flags may be added in future releases of SQLite. 4035** 4036** <dl> 4037** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 4038** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 4039** that the prepared statement will be retained for a long time and 4040** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 4041** and [sqlite3_prepare16_v3()] assume that the prepared statement will 4042** be used just once or at most a few times and then destroyed using 4043** [sqlite3_finalize()] relatively soon. The current implementation acts 4044** on this hint by avoiding the use of [lookaside memory] so as not to 4045** deplete the limited store of lookaside memory. Future versions of 4046** SQLite may act on this hint differently. 4047** 4048** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 4049** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 4050** to be required for any prepared statement that wanted to use the 4051** [sqlite3_normalized_sql()] interface. However, the 4052** [sqlite3_normalized_sql()] interface is now available to all 4053** prepared statements, regardless of whether or not they use this 4054** flag. 4055** 4056** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 4057** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 4058** to return an error (error code SQLITE_ERROR) if the statement uses 4059** any virtual tables. 4060** </dl> 4061*/ 4062#define SQLITE_PREPARE_PERSISTENT 0x01 4063#define SQLITE_PREPARE_NORMALIZE 0x02 4064#define SQLITE_PREPARE_NO_VTAB 0x04 4065 4066/* 4067** CAPI3REF: Compiling An SQL Statement 4068** KEYWORDS: {SQL statement compiler} 4069** METHOD: sqlite3 4070** CONSTRUCTOR: sqlite3_stmt 4071** 4072** To execute an SQL statement, it must first be compiled into a byte-code 4073** program using one of these routines. Or, in other words, these routines 4074** are constructors for the [prepared statement] object. 4075** 4076** The preferred routine to use is [sqlite3_prepare_v2()]. The 4077** [sqlite3_prepare()] interface is legacy and should be avoided. 4078** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 4079** for special purposes. 4080** 4081** The use of the UTF-8 interfaces is preferred, as SQLite currently 4082** does all parsing using UTF-8. The UTF-16 interfaces are provided 4083** as a convenience. The UTF-16 interfaces work by converting the 4084** input text into UTF-8, then invoking the corresponding UTF-8 interface. 4085** 4086** The first argument, "db", is a [database connection] obtained from a 4087** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 4088** [sqlite3_open16()]. The database connection must not have been closed. 4089** 4090** The second argument, "zSql", is the statement to be compiled, encoded 4091** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 4092** and sqlite3_prepare_v3() 4093** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 4094** and sqlite3_prepare16_v3() use UTF-16. 4095** 4096** ^If the nByte argument is negative, then zSql is read up to the 4097** first zero terminator. ^If nByte is positive, then it is the 4098** number of bytes read from zSql. ^If nByte is zero, then no prepared 4099** statement is generated. 4100** If the caller knows that the supplied string is nul-terminated, then 4101** there is a small performance advantage to passing an nByte parameter that 4102** is the number of bytes in the input string <i>including</i> 4103** the nul-terminator. 4104** 4105** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4106** past the end of the first SQL statement in zSql. These routines only 4107** compile the first statement in zSql, so *pzTail is left pointing to 4108** what remains uncompiled. 4109** 4110** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4111** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4112** to NULL. ^If the input text contains no SQL (if the input is an empty 4113** string or a comment) then *ppStmt is set to NULL. 4114** The calling procedure is responsible for deleting the compiled 4115** SQL statement using [sqlite3_finalize()] after it has finished with it. 4116** ppStmt may not be NULL. 4117** 4118** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4119** otherwise an [error code] is returned. 4120** 4121** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4122** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4123** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4124** are retained for backwards compatibility, but their use is discouraged. 4125** ^In the "vX" interfaces, the prepared statement 4126** that is returned (the [sqlite3_stmt] object) contains a copy of the 4127** original SQL text. This causes the [sqlite3_step()] interface to 4128** behave differently in three ways: 4129** 4130** <ol> 4131** <li> 4132** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4133** always used to do, [sqlite3_step()] will automatically recompile the SQL 4134** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4135** retries will occur before sqlite3_step() gives up and returns an error. 4136** </li> 4137** 4138** <li> 4139** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4140** [error codes] or [extended error codes]. ^The legacy behavior was that 4141** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4142** and the application would have to make a second call to [sqlite3_reset()] 4143** in order to find the underlying cause of the problem. With the "v2" prepare 4144** interfaces, the underlying reason for the error is returned immediately. 4145** </li> 4146** 4147** <li> 4148** ^If the specific value bound to a [parameter | host parameter] in the 4149** WHERE clause might influence the choice of query plan for a statement, 4150** then the statement will be automatically recompiled, as if there had been 4151** a schema change, on the first [sqlite3_step()] call following any change 4152** to the [sqlite3_bind_text | bindings] of that [parameter]. 4153** ^The specific value of a WHERE-clause [parameter] might influence the 4154** choice of query plan if the parameter is the left-hand side of a [LIKE] 4155** or [GLOB] operator or if the parameter is compared to an indexed column 4156** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4157** </li> 4158** </ol> 4159** 4160** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4161** the extra prepFlags parameter, which is a bit array consisting of zero or 4162** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4163** sqlite3_prepare_v2() interface works exactly the same as 4164** sqlite3_prepare_v3() with a zero prepFlags parameter. 4165*/ 4166int sqlite3_prepare( 4167 sqlite3 *db, /* Database handle */ 4168 const char *zSql, /* SQL statement, UTF-8 encoded */ 4169 int nByte, /* Maximum length of zSql in bytes. */ 4170 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4171 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4172); 4173int sqlite3_prepare_v2( 4174 sqlite3 *db, /* Database handle */ 4175 const char *zSql, /* SQL statement, UTF-8 encoded */ 4176 int nByte, /* Maximum length of zSql in bytes. */ 4177 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4178 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4179); 4180int sqlite3_prepare_v3( 4181 sqlite3 *db, /* Database handle */ 4182 const char *zSql, /* SQL statement, UTF-8 encoded */ 4183 int nByte, /* Maximum length of zSql in bytes. */ 4184 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4185 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4186 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4187); 4188int sqlite3_prepare16( 4189 sqlite3 *db, /* Database handle */ 4190 const void *zSql, /* SQL statement, UTF-16 encoded */ 4191 int nByte, /* Maximum length of zSql in bytes. */ 4192 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4193 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4194); 4195int sqlite3_prepare16_v2( 4196 sqlite3 *db, /* Database handle */ 4197 const void *zSql, /* SQL statement, UTF-16 encoded */ 4198 int nByte, /* Maximum length of zSql in bytes. */ 4199 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4200 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4201); 4202int sqlite3_prepare16_v3( 4203 sqlite3 *db, /* Database handle */ 4204 const void *zSql, /* SQL statement, UTF-16 encoded */ 4205 int nByte, /* Maximum length of zSql in bytes. */ 4206 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4207 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4208 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4209); 4210 4211/* 4212** CAPI3REF: Retrieving Statement SQL 4213** METHOD: sqlite3_stmt 4214** 4215** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4216** SQL text used to create [prepared statement] P if P was 4217** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4218** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4219** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4220** string containing the SQL text of prepared statement P with 4221** [bound parameters] expanded. 4222** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4223** string containing the normalized SQL text of prepared statement P. The 4224** semantics used to normalize a SQL statement are unspecified and subject 4225** to change. At a minimum, literal values will be replaced with suitable 4226** placeholders. 4227** 4228** ^(For example, if a prepared statement is created using the SQL 4229** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4230** and parameter :xyz is unbound, then sqlite3_sql() will return 4231** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4232** will return "SELECT 2345,NULL".)^ 4233** 4234** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4235** is available to hold the result, or if the result would exceed the 4236** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4237** 4238** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4239** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4240** option causes sqlite3_expanded_sql() to always return NULL. 4241** 4242** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4243** are managed by SQLite and are automatically freed when the prepared 4244** statement is finalized. 4245** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4246** is obtained from [sqlite3_malloc()] and must be freed by the application 4247** by passing it to [sqlite3_free()]. 4248** 4249** ^The sqlite3_normalized_sql() interface is only available if 4250** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. 4251*/ 4252const char *sqlite3_sql(sqlite3_stmt *pStmt); 4253char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4254#ifdef SQLITE_ENABLE_NORMALIZE 4255const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4256#endif 4257 4258/* 4259** CAPI3REF: Determine If An SQL Statement Writes The Database 4260** METHOD: sqlite3_stmt 4261** 4262** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4263** and only if the [prepared statement] X makes no direct changes to 4264** the content of the database file. 4265** 4266** Note that [application-defined SQL functions] or 4267** [virtual tables] might change the database indirectly as a side effect. 4268** ^(For example, if an application defines a function "eval()" that 4269** calls [sqlite3_exec()], then the following SQL statement would 4270** change the database file through side-effects: 4271** 4272** <blockquote><pre> 4273** SELECT eval('DELETE FROM t1') FROM t2; 4274** </pre></blockquote> 4275** 4276** But because the [SELECT] statement does not change the database file 4277** directly, sqlite3_stmt_readonly() would still return true.)^ 4278** 4279** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4280** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4281** since the statements themselves do not actually modify the database but 4282** rather they control the timing of when other statements modify the 4283** database. ^The [ATTACH] and [DETACH] statements also cause 4284** sqlite3_stmt_readonly() to return true since, while those statements 4285** change the configuration of a database connection, they do not make 4286** changes to the content of the database files on disk. 4287** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4288** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4289** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4290** sqlite3_stmt_readonly() returns false for those commands. 4291** 4292** ^This routine returns false if there is any possibility that the 4293** statement might change the database file. ^A false return does 4294** not guarantee that the statement will change the database file. 4295** ^For example, an UPDATE statement might have a WHERE clause that 4296** makes it a no-op, but the sqlite3_stmt_readonly() result would still 4297** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a 4298** read-only no-op if the table already exists, but 4299** sqlite3_stmt_readonly() still returns false for such a statement. 4300** 4301** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] 4302** statement, then sqlite3_stmt_readonly(X) returns the same value as 4303** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. 4304*/ 4305int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4306 4307/* 4308** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4309** METHOD: sqlite3_stmt 4310** 4311** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4312** prepared statement S is an EXPLAIN statement, or 2 if the 4313** statement S is an EXPLAIN QUERY PLAN. 4314** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4315** an ordinary statement or a NULL pointer. 4316*/ 4317int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4318 4319/* 4320** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4321** METHOD: sqlite3_stmt 4322** 4323** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4324** [prepared statement] S has been stepped at least once using 4325** [sqlite3_step(S)] but has neither run to completion (returned 4326** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4327** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4328** interface returns false if S is a NULL pointer. If S is not a 4329** NULL pointer and is not a pointer to a valid [prepared statement] 4330** object, then the behavior is undefined and probably undesirable. 4331** 4332** This interface can be used in combination [sqlite3_next_stmt()] 4333** to locate all prepared statements associated with a database 4334** connection that are in need of being reset. This can be used, 4335** for example, in diagnostic routines to search for prepared 4336** statements that are holding a transaction open. 4337*/ 4338int sqlite3_stmt_busy(sqlite3_stmt*); 4339 4340/* 4341** CAPI3REF: Dynamically Typed Value Object 4342** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4343** 4344** SQLite uses the sqlite3_value object to represent all values 4345** that can be stored in a database table. SQLite uses dynamic typing 4346** for the values it stores. ^Values stored in sqlite3_value objects 4347** can be integers, floating point values, strings, BLOBs, or NULL. 4348** 4349** An sqlite3_value object may be either "protected" or "unprotected". 4350** Some interfaces require a protected sqlite3_value. Other interfaces 4351** will accept either a protected or an unprotected sqlite3_value. 4352** Every interface that accepts sqlite3_value arguments specifies 4353** whether or not it requires a protected sqlite3_value. The 4354** [sqlite3_value_dup()] interface can be used to construct a new 4355** protected sqlite3_value from an unprotected sqlite3_value. 4356** 4357** The terms "protected" and "unprotected" refer to whether or not 4358** a mutex is held. An internal mutex is held for a protected 4359** sqlite3_value object but no mutex is held for an unprotected 4360** sqlite3_value object. If SQLite is compiled to be single-threaded 4361** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4362** or if SQLite is run in one of reduced mutex modes 4363** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4364** then there is no distinction between protected and unprotected 4365** sqlite3_value objects and they can be used interchangeably. However, 4366** for maximum code portability it is recommended that applications 4367** still make the distinction between protected and unprotected 4368** sqlite3_value objects even when not strictly required. 4369** 4370** ^The sqlite3_value objects that are passed as parameters into the 4371** implementation of [application-defined SQL functions] are protected. 4372** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] 4373** are protected. 4374** ^The sqlite3_value object returned by 4375** [sqlite3_column_value()] is unprotected. 4376** Unprotected sqlite3_value objects may only be used as arguments 4377** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4378** [sqlite3_value_dup()]. 4379** The [sqlite3_value_blob | sqlite3_value_type()] family of 4380** interfaces require protected sqlite3_value objects. 4381*/ 4382typedef struct sqlite3_value sqlite3_value; 4383 4384/* 4385** CAPI3REF: SQL Function Context Object 4386** 4387** The context in which an SQL function executes is stored in an 4388** sqlite3_context object. ^A pointer to an sqlite3_context object 4389** is always first parameter to [application-defined SQL functions]. 4390** The application-defined SQL function implementation will pass this 4391** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4392** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4393** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4394** and/or [sqlite3_set_auxdata()]. 4395*/ 4396typedef struct sqlite3_context sqlite3_context; 4397 4398/* 4399** CAPI3REF: Binding Values To Prepared Statements 4400** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4401** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4402** METHOD: sqlite3_stmt 4403** 4404** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4405** literals may be replaced by a [parameter] that matches one of following 4406** templates: 4407** 4408** <ul> 4409** <li> ? 4410** <li> ?NNN 4411** <li> :VVV 4412** <li> @VVV 4413** <li> $VVV 4414** </ul> 4415** 4416** In the templates above, NNN represents an integer literal, 4417** and VVV represents an alphanumeric identifier.)^ ^The values of these 4418** parameters (also called "host parameter names" or "SQL parameters") 4419** can be set using the sqlite3_bind_*() routines defined here. 4420** 4421** ^The first argument to the sqlite3_bind_*() routines is always 4422** a pointer to the [sqlite3_stmt] object returned from 4423** [sqlite3_prepare_v2()] or its variants. 4424** 4425** ^The second argument is the index of the SQL parameter to be set. 4426** ^The leftmost SQL parameter has an index of 1. ^When the same named 4427** SQL parameter is used more than once, second and subsequent 4428** occurrences have the same index as the first occurrence. 4429** ^The index for named parameters can be looked up using the 4430** [sqlite3_bind_parameter_index()] API if desired. ^The index 4431** for "?NNN" parameters is the value of NNN. 4432** ^The NNN value must be between 1 and the [sqlite3_limit()] 4433** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4434** 4435** ^The third argument is the value to bind to the parameter. 4436** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4437** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4438** is ignored and the end result is the same as sqlite3_bind_null(). 4439** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4440** it should be a pointer to well-formed UTF8 text. 4441** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4442** it should be a pointer to well-formed UTF16 text. 4443** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4444** it should be a pointer to a well-formed unicode string that is 4445** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 4446** otherwise. 4447** 4448** [[byte-order determination rules]] ^The byte-order of 4449** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4450** found in first character, which is removed, or in the absence of a BOM 4451** the byte order is the native byte order of the host 4452** machine for sqlite3_bind_text16() or the byte order specified in 4453** the 6th parameter for sqlite3_bind_text64().)^ 4454** ^If UTF16 input text contains invalid unicode 4455** characters, then SQLite might change those invalid characters 4456** into the unicode replacement character: U+FFFD. 4457** 4458** ^(In those routines that have a fourth argument, its value is the 4459** number of bytes in the parameter. To be clear: the value is the 4460** number of <u>bytes</u> in the value, not the number of characters.)^ 4461** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4462** is negative, then the length of the string is 4463** the number of bytes up to the first zero terminator. 4464** If the fourth parameter to sqlite3_bind_blob() is negative, then 4465** the behavior is undefined. 4466** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4467** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4468** that parameter must be the byte offset 4469** where the NUL terminator would occur assuming the string were NUL 4470** terminated. If any NUL characters occurs at byte offsets less than 4471** the value of the fourth parameter then the resulting string value will 4472** contain embedded NULs. The result of expressions involving strings 4473** with embedded NULs is undefined. 4474** 4475** ^The fifth argument to the BLOB and string binding interfaces controls 4476** or indicates the lifetime of the object referenced by the third parameter. 4477** These three options exist: 4478** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished 4479** with it may be passed. ^It is called to dispose of the BLOB or string even 4480** if the call to the bind API fails, except the destructor is not called if 4481** the third parameter is a NULL pointer or the fourth parameter is negative. 4482** ^ (2) The special constant, [SQLITE_STATIC], may be passsed to indicate that 4483** the application remains responsible for disposing of the object. ^In this 4484** case, the object and the provided pointer to it must remain valid until 4485** either the prepared statement is finalized or the same SQL parameter is 4486** bound to something else, whichever occurs sooner. 4487** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the 4488** object is to be copied prior to the return from sqlite3_bind_*(). ^The 4489** object and pointer to it must remain valid until then. ^SQLite will then 4490** manage the lifetime of its private copy. 4491** 4492** ^The sixth argument to sqlite3_bind_text64() must be one of 4493** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4494** to specify the encoding of the text in the third parameter. If 4495** the sixth argument to sqlite3_bind_text64() is not one of the 4496** allowed values shown above, or if the text encoding is different 4497** from the encoding specified by the sixth parameter, then the behavior 4498** is undefined. 4499** 4500** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4501** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4502** (just an integer to hold its size) while it is being processed. 4503** Zeroblobs are intended to serve as placeholders for BLOBs whose 4504** content is later written using 4505** [sqlite3_blob_open | incremental BLOB I/O] routines. 4506** ^A negative value for the zeroblob results in a zero-length BLOB. 4507** 4508** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4509** [prepared statement] S to have an SQL value of NULL, but to also be 4510** associated with the pointer P of type T. ^D is either a NULL pointer or 4511** a pointer to a destructor function for P. ^SQLite will invoke the 4512** destructor D with a single argument of P when it is finished using 4513** P. The T parameter should be a static string, preferably a string 4514** literal. The sqlite3_bind_pointer() routine is part of the 4515** [pointer passing interface] added for SQLite 3.20.0. 4516** 4517** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4518** for the [prepared statement] or with a prepared statement for which 4519** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4520** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4521** routine is passed a [prepared statement] that has been finalized, the 4522** result is undefined and probably harmful. 4523** 4524** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4525** ^Unbound parameters are interpreted as NULL. 4526** 4527** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4528** [error code] if anything goes wrong. 4529** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4530** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4531** [SQLITE_MAX_LENGTH]. 4532** ^[SQLITE_RANGE] is returned if the parameter 4533** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4534** 4535** See also: [sqlite3_bind_parameter_count()], 4536** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4537*/ 4538int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4539int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4540 void(*)(void*)); 4541int sqlite3_bind_double(sqlite3_stmt*, int, double); 4542int sqlite3_bind_int(sqlite3_stmt*, int, int); 4543int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4544int sqlite3_bind_null(sqlite3_stmt*, int); 4545int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4546int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4547int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4548 void(*)(void*), unsigned char encoding); 4549int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4550int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4551int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4552int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4553 4554/* 4555** CAPI3REF: Number Of SQL Parameters 4556** METHOD: sqlite3_stmt 4557** 4558** ^This routine can be used to find the number of [SQL parameters] 4559** in a [prepared statement]. SQL parameters are tokens of the 4560** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4561** placeholders for values that are [sqlite3_bind_blob | bound] 4562** to the parameters at a later time. 4563** 4564** ^(This routine actually returns the index of the largest (rightmost) 4565** parameter. For all forms except ?NNN, this will correspond to the 4566** number of unique parameters. If parameters of the ?NNN form are used, 4567** there may be gaps in the list.)^ 4568** 4569** See also: [sqlite3_bind_blob|sqlite3_bind()], 4570** [sqlite3_bind_parameter_name()], and 4571** [sqlite3_bind_parameter_index()]. 4572*/ 4573int sqlite3_bind_parameter_count(sqlite3_stmt*); 4574 4575/* 4576** CAPI3REF: Name Of A Host Parameter 4577** METHOD: sqlite3_stmt 4578** 4579** ^The sqlite3_bind_parameter_name(P,N) interface returns 4580** the name of the N-th [SQL parameter] in the [prepared statement] P. 4581** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4582** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4583** respectively. 4584** In other words, the initial ":" or "$" or "@" or "?" 4585** is included as part of the name.)^ 4586** ^Parameters of the form "?" without a following integer have no name 4587** and are referred to as "nameless" or "anonymous parameters". 4588** 4589** ^The first host parameter has an index of 1, not 0. 4590** 4591** ^If the value N is out of range or if the N-th parameter is 4592** nameless, then NULL is returned. ^The returned string is 4593** always in UTF-8 encoding even if the named parameter was 4594** originally specified as UTF-16 in [sqlite3_prepare16()], 4595** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4596** 4597** See also: [sqlite3_bind_blob|sqlite3_bind()], 4598** [sqlite3_bind_parameter_count()], and 4599** [sqlite3_bind_parameter_index()]. 4600*/ 4601const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4602 4603/* 4604** CAPI3REF: Index Of A Parameter With A Given Name 4605** METHOD: sqlite3_stmt 4606** 4607** ^Return the index of an SQL parameter given its name. ^The 4608** index value returned is suitable for use as the second 4609** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4610** is returned if no matching parameter is found. ^The parameter 4611** name must be given in UTF-8 even if the original statement 4612** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4613** [sqlite3_prepare16_v3()]. 4614** 4615** See also: [sqlite3_bind_blob|sqlite3_bind()], 4616** [sqlite3_bind_parameter_count()], and 4617** [sqlite3_bind_parameter_name()]. 4618*/ 4619int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4620 4621/* 4622** CAPI3REF: Reset All Bindings On A Prepared Statement 4623** METHOD: sqlite3_stmt 4624** 4625** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4626** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4627** ^Use this routine to reset all host parameters to NULL. 4628*/ 4629int sqlite3_clear_bindings(sqlite3_stmt*); 4630 4631/* 4632** CAPI3REF: Number Of Columns In A Result Set 4633** METHOD: sqlite3_stmt 4634** 4635** ^Return the number of columns in the result set returned by the 4636** [prepared statement]. ^If this routine returns 0, that means the 4637** [prepared statement] returns no data (for example an [UPDATE]). 4638** ^However, just because this routine returns a positive number does not 4639** mean that one or more rows of data will be returned. ^A SELECT statement 4640** will always have a positive sqlite3_column_count() but depending on the 4641** WHERE clause constraints and the table content, it might return no rows. 4642** 4643** See also: [sqlite3_data_count()] 4644*/ 4645int sqlite3_column_count(sqlite3_stmt *pStmt); 4646 4647/* 4648** CAPI3REF: Column Names In A Result Set 4649** METHOD: sqlite3_stmt 4650** 4651** ^These routines return the name assigned to a particular column 4652** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4653** interface returns a pointer to a zero-terminated UTF-8 string 4654** and sqlite3_column_name16() returns a pointer to a zero-terminated 4655** UTF-16 string. ^The first parameter is the [prepared statement] 4656** that implements the [SELECT] statement. ^The second parameter is the 4657** column number. ^The leftmost column is number 0. 4658** 4659** ^The returned string pointer is valid until either the [prepared statement] 4660** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4661** reprepared by the first call to [sqlite3_step()] for a particular run 4662** or until the next call to 4663** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4664** 4665** ^If sqlite3_malloc() fails during the processing of either routine 4666** (for example during a conversion from UTF-8 to UTF-16) then a 4667** NULL pointer is returned. 4668** 4669** ^The name of a result column is the value of the "AS" clause for 4670** that column, if there is an AS clause. If there is no AS clause 4671** then the name of the column is unspecified and may change from 4672** one release of SQLite to the next. 4673*/ 4674const char *sqlite3_column_name(sqlite3_stmt*, int N); 4675const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4676 4677/* 4678** CAPI3REF: Source Of Data In A Query Result 4679** METHOD: sqlite3_stmt 4680** 4681** ^These routines provide a means to determine the database, table, and 4682** table column that is the origin of a particular result column in 4683** [SELECT] statement. 4684** ^The name of the database or table or column can be returned as 4685** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4686** the database name, the _table_ routines return the table name, and 4687** the origin_ routines return the column name. 4688** ^The returned string is valid until the [prepared statement] is destroyed 4689** using [sqlite3_finalize()] or until the statement is automatically 4690** reprepared by the first call to [sqlite3_step()] for a particular run 4691** or until the same information is requested 4692** again in a different encoding. 4693** 4694** ^The names returned are the original un-aliased names of the 4695** database, table, and column. 4696** 4697** ^The first argument to these interfaces is a [prepared statement]. 4698** ^These functions return information about the Nth result column returned by 4699** the statement, where N is the second function argument. 4700** ^The left-most column is column 0 for these routines. 4701** 4702** ^If the Nth column returned by the statement is an expression or 4703** subquery and is not a column value, then all of these functions return 4704** NULL. ^These routines might also return NULL if a memory allocation error 4705** occurs. ^Otherwise, they return the name of the attached database, table, 4706** or column that query result column was extracted from. 4707** 4708** ^As with all other SQLite APIs, those whose names end with "16" return 4709** UTF-16 encoded strings and the other functions return UTF-8. 4710** 4711** ^These APIs are only available if the library was compiled with the 4712** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4713** 4714** If two or more threads call one or more 4715** [sqlite3_column_database_name | column metadata interfaces] 4716** for the same [prepared statement] and result column 4717** at the same time then the results are undefined. 4718*/ 4719const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4720const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4721const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4722const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4723const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4724const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4725 4726/* 4727** CAPI3REF: Declared Datatype Of A Query Result 4728** METHOD: sqlite3_stmt 4729** 4730** ^(The first parameter is a [prepared statement]. 4731** If this statement is a [SELECT] statement and the Nth column of the 4732** returned result set of that [SELECT] is a table column (not an 4733** expression or subquery) then the declared type of the table 4734** column is returned.)^ ^If the Nth column of the result set is an 4735** expression or subquery, then a NULL pointer is returned. 4736** ^The returned string is always UTF-8 encoded. 4737** 4738** ^(For example, given the database schema: 4739** 4740** CREATE TABLE t1(c1 VARIANT); 4741** 4742** and the following statement to be compiled: 4743** 4744** SELECT c1 + 1, c1 FROM t1; 4745** 4746** this routine would return the string "VARIANT" for the second result 4747** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4748** 4749** ^SQLite uses dynamic run-time typing. ^So just because a column 4750** is declared to contain a particular type does not mean that the 4751** data stored in that column is of the declared type. SQLite is 4752** strongly typed, but the typing is dynamic not static. ^Type 4753** is associated with individual values, not with the containers 4754** used to hold those values. 4755*/ 4756const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4757const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4758 4759/* 4760** CAPI3REF: Evaluate An SQL Statement 4761** METHOD: sqlite3_stmt 4762** 4763** After a [prepared statement] has been prepared using any of 4764** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4765** or [sqlite3_prepare16_v3()] or one of the legacy 4766** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4767** must be called one or more times to evaluate the statement. 4768** 4769** The details of the behavior of the sqlite3_step() interface depend 4770** on whether the statement was prepared using the newer "vX" interfaces 4771** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4772** [sqlite3_prepare16_v2()] or the older legacy 4773** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4774** new "vX" interface is recommended for new applications but the legacy 4775** interface will continue to be supported. 4776** 4777** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4778** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4779** ^With the "v2" interface, any of the other [result codes] or 4780** [extended result codes] might be returned as well. 4781** 4782** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4783** database locks it needs to do its job. ^If the statement is a [COMMIT] 4784** or occurs outside of an explicit transaction, then you can retry the 4785** statement. If the statement is not a [COMMIT] and occurs within an 4786** explicit transaction then you should rollback the transaction before 4787** continuing. 4788** 4789** ^[SQLITE_DONE] means that the statement has finished executing 4790** successfully. sqlite3_step() should not be called again on this virtual 4791** machine without first calling [sqlite3_reset()] to reset the virtual 4792** machine back to its initial state. 4793** 4794** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4795** is returned each time a new row of data is ready for processing by the 4796** caller. The values may be accessed using the [column access functions]. 4797** sqlite3_step() is called again to retrieve the next row of data. 4798** 4799** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4800** violation) has occurred. sqlite3_step() should not be called again on 4801** the VM. More information may be found by calling [sqlite3_errmsg()]. 4802** ^With the legacy interface, a more specific error code (for example, 4803** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4804** can be obtained by calling [sqlite3_reset()] on the 4805** [prepared statement]. ^In the "v2" interface, 4806** the more specific error code is returned directly by sqlite3_step(). 4807** 4808** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4809** Perhaps it was called on a [prepared statement] that has 4810** already been [sqlite3_finalize | finalized] or on one that had 4811** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4812** be the case that the same database connection is being used by two or 4813** more threads at the same moment in time. 4814** 4815** For all versions of SQLite up to and including 3.6.23.1, a call to 4816** [sqlite3_reset()] was required after sqlite3_step() returned anything 4817** other than [SQLITE_ROW] before any subsequent invocation of 4818** sqlite3_step(). Failure to reset the prepared statement using 4819** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4820** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4821** sqlite3_step() began 4822** calling [sqlite3_reset()] automatically in this circumstance rather 4823** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4824** break because any application that ever receives an SQLITE_MISUSE error 4825** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4826** can be used to restore the legacy behavior. 4827** 4828** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4829** API always returns a generic error code, [SQLITE_ERROR], following any 4830** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4831** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4832** specific [error codes] that better describes the error. 4833** We admit that this is a goofy design. The problem has been fixed 4834** with the "v2" interface. If you prepare all of your SQL statements 4835** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4836** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 4837** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 4838** then the more specific [error codes] are returned directly 4839** by sqlite3_step(). The use of the "vX" interfaces is recommended. 4840*/ 4841int sqlite3_step(sqlite3_stmt*); 4842 4843/* 4844** CAPI3REF: Number of columns in a result set 4845** METHOD: sqlite3_stmt 4846** 4847** ^The sqlite3_data_count(P) interface returns the number of columns in the 4848** current row of the result set of [prepared statement] P. 4849** ^If prepared statement P does not have results ready to return 4850** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 4851** interfaces) then sqlite3_data_count(P) returns 0. 4852** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 4853** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 4854** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 4855** will return non-zero if previous call to [sqlite3_step](P) returned 4856** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 4857** where it always returns zero since each step of that multi-step 4858** pragma returns 0 columns of data. 4859** 4860** See also: [sqlite3_column_count()] 4861*/ 4862int sqlite3_data_count(sqlite3_stmt *pStmt); 4863 4864/* 4865** CAPI3REF: Fundamental Datatypes 4866** KEYWORDS: SQLITE_TEXT 4867** 4868** ^(Every value in SQLite has one of five fundamental datatypes: 4869** 4870** <ul> 4871** <li> 64-bit signed integer 4872** <li> 64-bit IEEE floating point number 4873** <li> string 4874** <li> BLOB 4875** <li> NULL 4876** </ul>)^ 4877** 4878** These constants are codes for each of those types. 4879** 4880** Note that the SQLITE_TEXT constant was also used in SQLite version 2 4881** for a completely different meaning. Software that links against both 4882** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 4883** SQLITE_TEXT. 4884*/ 4885#define SQLITE_INTEGER 1 4886#define SQLITE_FLOAT 2 4887#define SQLITE_BLOB 4 4888#define SQLITE_NULL 5 4889#ifdef SQLITE_TEXT 4890# undef SQLITE_TEXT 4891#else 4892# define SQLITE_TEXT 3 4893#endif 4894#define SQLITE3_TEXT 3 4895 4896/* 4897** CAPI3REF: Result Values From A Query 4898** KEYWORDS: {column access functions} 4899** METHOD: sqlite3_stmt 4900** 4901** <b>Summary:</b> 4902** <blockquote><table border=0 cellpadding=0 cellspacing=0> 4903** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 4904** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 4905** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 4906** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 4907** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 4908** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 4909** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 4910** [sqlite3_value|unprotected sqlite3_value] object. 4911** <tr><td> <td> <td> 4912** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 4913** or a UTF-8 TEXT result in bytes 4914** <tr><td><b>sqlite3_column_bytes16 </b> 4915** <td>→ <td>Size of UTF-16 4916** TEXT in bytes 4917** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 4918** datatype of the result 4919** </table></blockquote> 4920** 4921** <b>Details:</b> 4922** 4923** ^These routines return information about a single column of the current 4924** result row of a query. ^In every case the first argument is a pointer 4925** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 4926** that was returned from [sqlite3_prepare_v2()] or one of its variants) 4927** and the second argument is the index of the column for which information 4928** should be returned. ^The leftmost column of the result set has the index 0. 4929** ^The number of columns in the result can be determined using 4930** [sqlite3_column_count()]. 4931** 4932** If the SQL statement does not currently point to a valid row, or if the 4933** column index is out of range, the result is undefined. 4934** These routines may only be called when the most recent call to 4935** [sqlite3_step()] has returned [SQLITE_ROW] and neither 4936** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 4937** If any of these routines are called after [sqlite3_reset()] or 4938** [sqlite3_finalize()] or after [sqlite3_step()] has returned 4939** something other than [SQLITE_ROW], the results are undefined. 4940** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 4941** are called from a different thread while any of these routines 4942** are pending, then the results are undefined. 4943** 4944** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 4945** each return the value of a result column in a specific data format. If 4946** the result column is not initially in the requested format (for example, 4947** if the query returns an integer but the sqlite3_column_text() interface 4948** is used to extract the value) then an automatic type conversion is performed. 4949** 4950** ^The sqlite3_column_type() routine returns the 4951** [SQLITE_INTEGER | datatype code] for the initial data type 4952** of the result column. ^The returned value is one of [SQLITE_INTEGER], 4953** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 4954** The return value of sqlite3_column_type() can be used to decide which 4955** of the first six interface should be used to extract the column value. 4956** The value returned by sqlite3_column_type() is only meaningful if no 4957** automatic type conversions have occurred for the value in question. 4958** After a type conversion, the result of calling sqlite3_column_type() 4959** is undefined, though harmless. Future 4960** versions of SQLite may change the behavior of sqlite3_column_type() 4961** following a type conversion. 4962** 4963** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 4964** or sqlite3_column_bytes16() interfaces can be used to determine the size 4965** of that BLOB or string. 4966** 4967** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 4968** routine returns the number of bytes in that BLOB or string. 4969** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 4970** the string to UTF-8 and then returns the number of bytes. 4971** ^If the result is a numeric value then sqlite3_column_bytes() uses 4972** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 4973** the number of bytes in that string. 4974** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 4975** 4976** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 4977** routine returns the number of bytes in that BLOB or string. 4978** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 4979** the string to UTF-16 and then returns the number of bytes. 4980** ^If the result is a numeric value then sqlite3_column_bytes16() uses 4981** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 4982** the number of bytes in that string. 4983** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 4984** 4985** ^The values returned by [sqlite3_column_bytes()] and 4986** [sqlite3_column_bytes16()] do not include the zero terminators at the end 4987** of the string. ^For clarity: the values returned by 4988** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 4989** bytes in the string, not the number of characters. 4990** 4991** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 4992** even empty strings, are always zero-terminated. ^The return 4993** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 4994** 4995** ^Strings returned by sqlite3_column_text16() always have the endianness 4996** which is native to the platform, regardless of the text encoding set 4997** for the database. 4998** 4999** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 5000** [unprotected sqlite3_value] object. In a multithreaded environment, 5001** an unprotected sqlite3_value object may only be used safely with 5002** [sqlite3_bind_value()] and [sqlite3_result_value()]. 5003** If the [unprotected sqlite3_value] object returned by 5004** [sqlite3_column_value()] is used in any other way, including calls 5005** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 5006** or [sqlite3_value_bytes()], the behavior is not threadsafe. 5007** Hence, the sqlite3_column_value() interface 5008** is normally only useful within the implementation of 5009** [application-defined SQL functions] or [virtual tables], not within 5010** top-level application code. 5011** 5012** These routines may attempt to convert the datatype of the result. 5013** ^For example, if the internal representation is FLOAT and a text result 5014** is requested, [sqlite3_snprintf()] is used internally to perform the 5015** conversion automatically. ^(The following table details the conversions 5016** that are applied: 5017** 5018** <blockquote> 5019** <table border="1"> 5020** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 5021** 5022** <tr><td> NULL <td> INTEGER <td> Result is 0 5023** <tr><td> NULL <td> FLOAT <td> Result is 0.0 5024** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 5025** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 5026** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 5027** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 5028** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 5029** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 5030** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 5031** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 5032** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 5033** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 5034** <tr><td> TEXT <td> BLOB <td> No change 5035** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 5036** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 5037** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator 5038** </table> 5039** </blockquote>)^ 5040** 5041** Note that when type conversions occur, pointers returned by prior 5042** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 5043** sqlite3_column_text16() may be invalidated. 5044** Type conversions and pointer invalidations might occur 5045** in the following cases: 5046** 5047** <ul> 5048** <li> The initial content is a BLOB and sqlite3_column_text() or 5049** sqlite3_column_text16() is called. A zero-terminator might 5050** need to be added to the string.</li> 5051** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 5052** sqlite3_column_text16() is called. The content must be converted 5053** to UTF-16.</li> 5054** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 5055** sqlite3_column_text() is called. The content must be converted 5056** to UTF-8.</li> 5057** </ul> 5058** 5059** ^Conversions between UTF-16be and UTF-16le are always done in place and do 5060** not invalidate a prior pointer, though of course the content of the buffer 5061** that the prior pointer references will have been modified. Other kinds 5062** of conversion are done in place when it is possible, but sometimes they 5063** are not possible and in those cases prior pointers are invalidated. 5064** 5065** The safest policy is to invoke these routines 5066** in one of the following ways: 5067** 5068** <ul> 5069** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 5070** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 5071** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 5072** </ul> 5073** 5074** In other words, you should call sqlite3_column_text(), 5075** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 5076** into the desired format, then invoke sqlite3_column_bytes() or 5077** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 5078** to sqlite3_column_text() or sqlite3_column_blob() with calls to 5079** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 5080** with calls to sqlite3_column_bytes(). 5081** 5082** ^The pointers returned are valid until a type conversion occurs as 5083** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 5084** [sqlite3_finalize()] is called. ^The memory space used to hold strings 5085** and BLOBs is freed automatically. Do not pass the pointers returned 5086** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 5087** [sqlite3_free()]. 5088** 5089** As long as the input parameters are correct, these routines will only 5090** fail if an out-of-memory error occurs during a format conversion. 5091** Only the following subset of interfaces are subject to out-of-memory 5092** errors: 5093** 5094** <ul> 5095** <li> sqlite3_column_blob() 5096** <li> sqlite3_column_text() 5097** <li> sqlite3_column_text16() 5098** <li> sqlite3_column_bytes() 5099** <li> sqlite3_column_bytes16() 5100** </ul> 5101** 5102** If an out-of-memory error occurs, then the return value from these 5103** routines is the same as if the column had contained an SQL NULL value. 5104** Valid SQL NULL returns can be distinguished from out-of-memory errors 5105** by invoking the [sqlite3_errcode()] immediately after the suspect 5106** return value is obtained and before any 5107** other SQLite interface is called on the same [database connection]. 5108*/ 5109const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 5110double sqlite3_column_double(sqlite3_stmt*, int iCol); 5111int sqlite3_column_int(sqlite3_stmt*, int iCol); 5112sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 5113const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 5114const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 5115sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 5116int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 5117int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 5118int sqlite3_column_type(sqlite3_stmt*, int iCol); 5119 5120/* 5121** CAPI3REF: Destroy A Prepared Statement Object 5122** DESTRUCTOR: sqlite3_stmt 5123** 5124** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 5125** ^If the most recent evaluation of the statement encountered no errors 5126** or if the statement is never been evaluated, then sqlite3_finalize() returns 5127** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 5128** sqlite3_finalize(S) returns the appropriate [error code] or 5129** [extended error code]. 5130** 5131** ^The sqlite3_finalize(S) routine can be called at any point during 5132** the life cycle of [prepared statement] S: 5133** before statement S is ever evaluated, after 5134** one or more calls to [sqlite3_reset()], or after any call 5135** to [sqlite3_step()] regardless of whether or not the statement has 5136** completed execution. 5137** 5138** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5139** 5140** The application must finalize every [prepared statement] in order to avoid 5141** resource leaks. It is a grievous error for the application to try to use 5142** a prepared statement after it has been finalized. Any use of a prepared 5143** statement after it has been finalized can result in undefined and 5144** undesirable behavior such as segfaults and heap corruption. 5145*/ 5146int sqlite3_finalize(sqlite3_stmt *pStmt); 5147 5148/* 5149** CAPI3REF: Reset A Prepared Statement Object 5150** METHOD: sqlite3_stmt 5151** 5152** The sqlite3_reset() function is called to reset a [prepared statement] 5153** object back to its initial state, ready to be re-executed. 5154** ^Any SQL statement variables that had values bound to them using 5155** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5156** Use [sqlite3_clear_bindings()] to reset the bindings. 5157** 5158** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5159** back to the beginning of its program. 5160** 5161** ^If the most recent call to [sqlite3_step(S)] for the 5162** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 5163** or if [sqlite3_step(S)] has never before been called on S, 5164** then [sqlite3_reset(S)] returns [SQLITE_OK]. 5165** 5166** ^If the most recent call to [sqlite3_step(S)] for the 5167** [prepared statement] S indicated an error, then 5168** [sqlite3_reset(S)] returns an appropriate [error code]. 5169** 5170** ^The [sqlite3_reset(S)] interface does not change the values 5171** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5172*/ 5173int sqlite3_reset(sqlite3_stmt *pStmt); 5174 5175/* 5176** CAPI3REF: Create Or Redefine SQL Functions 5177** KEYWORDS: {function creation routines} 5178** METHOD: sqlite3 5179** 5180** ^These functions (collectively known as "function creation routines") 5181** are used to add SQL functions or aggregates or to redefine the behavior 5182** of existing SQL functions or aggregates. The only differences between 5183** the three "sqlite3_create_function*" routines are the text encoding 5184** expected for the second parameter (the name of the function being 5185** created) and the presence or absence of a destructor callback for 5186** the application data pointer. Function sqlite3_create_window_function() 5187** is similar, but allows the user to supply the extra callback functions 5188** needed by [aggregate window functions]. 5189** 5190** ^The first parameter is the [database connection] to which the SQL 5191** function is to be added. ^If an application uses more than one database 5192** connection then application-defined SQL functions must be added 5193** to each database connection separately. 5194** 5195** ^The second parameter is the name of the SQL function to be created or 5196** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5197** representation, exclusive of the zero-terminator. ^Note that the name 5198** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5199** ^Any attempt to create a function with a longer name 5200** will result in [SQLITE_MISUSE] being returned. 5201** 5202** ^The third parameter (nArg) 5203** is the number of arguments that the SQL function or 5204** aggregate takes. ^If this parameter is -1, then the SQL function or 5205** aggregate may take any number of arguments between 0 and the limit 5206** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5207** parameter is less than -1 or greater than 127 then the behavior is 5208** undefined. 5209** 5210** ^The fourth parameter, eTextRep, specifies what 5211** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5212** its parameters. The application should set this parameter to 5213** [SQLITE_UTF16LE] if the function implementation invokes 5214** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5215** implementation invokes [sqlite3_value_text16be()] on an input, or 5216** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5217** otherwise. ^The same SQL function may be registered multiple times using 5218** different preferred text encodings, with different implementations for 5219** each encoding. 5220** ^When multiple implementations of the same function are available, SQLite 5221** will pick the one that involves the least amount of data conversion. 5222** 5223** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5224** to signal that the function will always return the same result given 5225** the same inputs within a single SQL statement. Most SQL functions are 5226** deterministic. The built-in [random()] SQL function is an example of a 5227** function that is not deterministic. The SQLite query planner is able to 5228** perform additional optimizations on deterministic functions, so use 5229** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5230** 5231** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5232** flag, which if present prevents the function from being invoked from 5233** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5234** index expressions, or the WHERE clause of partial indexes. 5235** 5236** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5237** all application-defined SQL functions that do not need to be 5238** used inside of triggers, view, CHECK constraints, or other elements of 5239** the database schema. This flags is especially recommended for SQL 5240** functions that have side effects or reveal internal application state. 5241** Without this flag, an attacker might be able to modify the schema of 5242** a database file to include invocations of the function with parameters 5243** chosen by the attacker, which the application will then execute when 5244** the database file is opened and read. 5245** 5246** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5247** function can gain access to this pointer using [sqlite3_user_data()].)^ 5248** 5249** ^The sixth, seventh and eighth parameters passed to the three 5250** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5251** pointers to C-language functions that implement the SQL function or 5252** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5253** callback only; NULL pointers must be passed as the xStep and xFinal 5254** parameters. ^An aggregate SQL function requires an implementation of xStep 5255** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5256** SQL function or aggregate, pass NULL pointers for all three function 5257** callbacks. 5258** 5259** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5260** and xInverse) passed to sqlite3_create_window_function are pointers to 5261** C-language callbacks that implement the new function. xStep and xFinal 5262** must both be non-NULL. xValue and xInverse may either both be NULL, in 5263** which case a regular aggregate function is created, or must both be 5264** non-NULL, in which case the new function may be used as either an aggregate 5265** or aggregate window function. More details regarding the implementation 5266** of aggregate window functions are 5267** [user-defined window functions|available here]. 5268** 5269** ^(If the final parameter to sqlite3_create_function_v2() or 5270** sqlite3_create_window_function() is not NULL, then it is destructor for 5271** the application data pointer. The destructor is invoked when the function 5272** is deleted, either by being overloaded or when the database connection 5273** closes.)^ ^The destructor is also invoked if the call to 5274** sqlite3_create_function_v2() fails. ^When the destructor callback is 5275** invoked, it is passed a single argument which is a copy of the application 5276** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5277** 5278** ^It is permitted to register multiple implementations of the same 5279** functions with the same name but with either differing numbers of 5280** arguments or differing preferred text encodings. ^SQLite will use 5281** the implementation that most closely matches the way in which the 5282** SQL function is used. ^A function implementation with a non-negative 5283** nArg parameter is a better match than a function implementation with 5284** a negative nArg. ^A function where the preferred text encoding 5285** matches the database encoding is a better 5286** match than a function where the encoding is different. 5287** ^A function where the encoding difference is between UTF16le and UTF16be 5288** is a closer match than a function where the encoding difference is 5289** between UTF8 and UTF16. 5290** 5291** ^Built-in functions may be overloaded by new application-defined functions. 5292** 5293** ^An application-defined function is permitted to call other 5294** SQLite interfaces. However, such calls must not 5295** close the database connection nor finalize or reset the prepared 5296** statement in which the function is running. 5297*/ 5298int sqlite3_create_function( 5299 sqlite3 *db, 5300 const char *zFunctionName, 5301 int nArg, 5302 int eTextRep, 5303 void *pApp, 5304 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5305 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5306 void (*xFinal)(sqlite3_context*) 5307); 5308int sqlite3_create_function16( 5309 sqlite3 *db, 5310 const void *zFunctionName, 5311 int nArg, 5312 int eTextRep, 5313 void *pApp, 5314 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5315 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5316 void (*xFinal)(sqlite3_context*) 5317); 5318int sqlite3_create_function_v2( 5319 sqlite3 *db, 5320 const char *zFunctionName, 5321 int nArg, 5322 int eTextRep, 5323 void *pApp, 5324 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5325 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5326 void (*xFinal)(sqlite3_context*), 5327 void(*xDestroy)(void*) 5328); 5329int sqlite3_create_window_function( 5330 sqlite3 *db, 5331 const char *zFunctionName, 5332 int nArg, 5333 int eTextRep, 5334 void *pApp, 5335 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5336 void (*xFinal)(sqlite3_context*), 5337 void (*xValue)(sqlite3_context*), 5338 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5339 void(*xDestroy)(void*) 5340); 5341 5342/* 5343** CAPI3REF: Text Encodings 5344** 5345** These constant define integer codes that represent the various 5346** text encodings supported by SQLite. 5347*/ 5348#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5349#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5350#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5351#define SQLITE_UTF16 4 /* Use native byte order */ 5352#define SQLITE_ANY 5 /* Deprecated */ 5353#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5354 5355/* 5356** CAPI3REF: Function Flags 5357** 5358** These constants may be ORed together with the 5359** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5360** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5361** [sqlite3_create_function_v2()]. 5362** 5363** <dl> 5364** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5365** The SQLITE_DETERMINISTIC flag means that the new function always gives 5366** the same output when the input parameters are the same. 5367** The [abs|abs() function] is deterministic, for example, but 5368** [randomblob|randomblob()] is not. Functions must 5369** be deterministic in order to be used in certain contexts such as 5370** with the WHERE clause of [partial indexes] or in [generated columns]. 5371** SQLite might also optimize deterministic functions by factoring them 5372** out of inner loops. 5373** </dd> 5374** 5375** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5376** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5377** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5378** schema structures such as [CHECK constraints], [DEFAULT clauses], 5379** [expression indexes], [partial indexes], or [generated columns]. 5380** The SQLITE_DIRECTONLY flags is a security feature which is recommended 5381** for all [application-defined SQL functions], and especially for functions 5382** that have side-effects or that could potentially leak sensitive 5383** information. 5384** </dd> 5385** 5386** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5387** The SQLITE_INNOCUOUS flag means that the function is unlikely 5388** to cause problems even if misused. An innocuous function should have 5389** no side effects and should not depend on any values other than its 5390** input parameters. The [abs|abs() function] is an example of an 5391** innocuous function. 5392** The [load_extension() SQL function] is not innocuous because of its 5393** side effects. 5394** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5395** exactly the same. The [random|random() function] is an example of a 5396** function that is innocuous but not deterministic. 5397** <p>Some heightened security settings 5398** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5399** disable the use of SQL functions inside views and triggers and in 5400** schema structures such as [CHECK constraints], [DEFAULT clauses], 5401** [expression indexes], [partial indexes], and [generated columns] unless 5402** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5403** are innocuous. Developers are advised to avoid using the 5404** SQLITE_INNOCUOUS flag for application-defined functions unless the 5405** function has been carefully audited and found to be free of potentially 5406** security-adverse side-effects and information-leaks. 5407** </dd> 5408** 5409** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5410** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call 5411** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5412** Specifying this flag makes no difference for scalar or aggregate user 5413** functions. However, if it is not specified for a user-defined window 5414** function, then any sub-types belonging to arguments passed to the window 5415** function may be discarded before the window function is called (i.e. 5416** sqlite3_value_subtype() will always return 0). 5417** </dd> 5418** </dl> 5419*/ 5420#define SQLITE_DETERMINISTIC 0x000000800 5421#define SQLITE_DIRECTONLY 0x000080000 5422#define SQLITE_SUBTYPE 0x000100000 5423#define SQLITE_INNOCUOUS 0x000200000 5424 5425/* 5426** CAPI3REF: Deprecated Functions 5427** DEPRECATED 5428** 5429** These functions are [deprecated]. In order to maintain 5430** backwards compatibility with older code, these functions continue 5431** to be supported. However, new applications should avoid 5432** the use of these functions. To encourage programmers to avoid 5433** these functions, we will not explain what they do. 5434*/ 5435#ifndef SQLITE_OMIT_DEPRECATED 5436SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5437SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5438SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5439SQLITE_DEPRECATED int sqlite3_global_recover(void); 5440SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5441SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5442 void*,sqlite3_int64); 5443#endif 5444 5445/* 5446** CAPI3REF: Obtaining SQL Values 5447** METHOD: sqlite3_value 5448** 5449** <b>Summary:</b> 5450** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5451** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5452** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5453** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5454** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5455** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5456** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5457** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5458** the native byteorder 5459** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5460** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5461** <tr><td> <td> <td> 5462** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5463** or a UTF-8 TEXT in bytes 5464** <tr><td><b>sqlite3_value_bytes16 </b> 5465** <td>→ <td>Size of UTF-16 5466** TEXT in bytes 5467** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5468** datatype of the value 5469** <tr><td><b>sqlite3_value_numeric_type </b> 5470** <td>→ <td>Best numeric datatype of the value 5471** <tr><td><b>sqlite3_value_nochange </b> 5472** <td>→ <td>True if the column is unchanged in an UPDATE 5473** against a virtual table. 5474** <tr><td><b>sqlite3_value_frombind </b> 5475** <td>→ <td>True if value originated from a [bound parameter] 5476** </table></blockquote> 5477** 5478** <b>Details:</b> 5479** 5480** These routines extract type, size, and content information from 5481** [protected sqlite3_value] objects. Protected sqlite3_value objects 5482** are used to pass parameter information into the functions that 5483** implement [application-defined SQL functions] and [virtual tables]. 5484** 5485** These routines work only with [protected sqlite3_value] objects. 5486** Any attempt to use these routines on an [unprotected sqlite3_value] 5487** is not threadsafe. 5488** 5489** ^These routines work just like the corresponding [column access functions] 5490** except that these routines take a single [protected sqlite3_value] object 5491** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5492** 5493** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5494** in the native byte-order of the host machine. ^The 5495** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5496** extract UTF-16 strings as big-endian and little-endian respectively. 5497** 5498** ^If [sqlite3_value] object V was initialized 5499** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5500** and if X and Y are strings that compare equal according to strcmp(X,Y), 5501** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5502** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5503** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5504** 5505** ^(The sqlite3_value_type(V) interface returns the 5506** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5507** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5508** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5509** Other interfaces might change the datatype for an sqlite3_value object. 5510** For example, if the datatype is initially SQLITE_INTEGER and 5511** sqlite3_value_text(V) is called to extract a text value for that 5512** integer, then subsequent calls to sqlite3_value_type(V) might return 5513** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5514** occurs is undefined and may change from one release of SQLite to the next. 5515** 5516** ^(The sqlite3_value_numeric_type() interface attempts to apply 5517** numeric affinity to the value. This means that an attempt is 5518** made to convert the value to an integer or floating point. If 5519** such a conversion is possible without loss of information (in other 5520** words, if the value is a string that looks like a number) 5521** then the conversion is performed. Otherwise no conversion occurs. 5522** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5523** 5524** ^Within the [xUpdate] method of a [virtual table], the 5525** sqlite3_value_nochange(X) interface returns true if and only if 5526** the column corresponding to X is unchanged by the UPDATE operation 5527** that the xUpdate method call was invoked to implement and if 5528** and the prior [xColumn] method call that was invoked to extracted 5529** the value for that column returned without setting a result (probably 5530** because it queried [sqlite3_vtab_nochange()] and found that the column 5531** was unchanging). ^Within an [xUpdate] method, any value for which 5532** sqlite3_value_nochange(X) is true will in all other respects appear 5533** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5534** than within an [xUpdate] method call for an UPDATE statement, then 5535** the return value is arbitrary and meaningless. 5536** 5537** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5538** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5539** interfaces. ^If X comes from an SQL literal value, or a table column, 5540** or an expression, then sqlite3_value_frombind(X) returns zero. 5541** 5542** Please pay particular attention to the fact that the pointer returned 5543** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5544** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5545** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5546** or [sqlite3_value_text16()]. 5547** 5548** These routines must be called from the same thread as 5549** the SQL function that supplied the [sqlite3_value*] parameters. 5550** 5551** As long as the input parameter is correct, these routines can only 5552** fail if an out-of-memory error occurs during a format conversion. 5553** Only the following subset of interfaces are subject to out-of-memory 5554** errors: 5555** 5556** <ul> 5557** <li> sqlite3_value_blob() 5558** <li> sqlite3_value_text() 5559** <li> sqlite3_value_text16() 5560** <li> sqlite3_value_text16le() 5561** <li> sqlite3_value_text16be() 5562** <li> sqlite3_value_bytes() 5563** <li> sqlite3_value_bytes16() 5564** </ul> 5565** 5566** If an out-of-memory error occurs, then the return value from these 5567** routines is the same as if the column had contained an SQL NULL value. 5568** Valid SQL NULL returns can be distinguished from out-of-memory errors 5569** by invoking the [sqlite3_errcode()] immediately after the suspect 5570** return value is obtained and before any 5571** other SQLite interface is called on the same [database connection]. 5572*/ 5573const void *sqlite3_value_blob(sqlite3_value*); 5574double sqlite3_value_double(sqlite3_value*); 5575int sqlite3_value_int(sqlite3_value*); 5576sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5577void *sqlite3_value_pointer(sqlite3_value*, const char*); 5578const unsigned char *sqlite3_value_text(sqlite3_value*); 5579const void *sqlite3_value_text16(sqlite3_value*); 5580const void *sqlite3_value_text16le(sqlite3_value*); 5581const void *sqlite3_value_text16be(sqlite3_value*); 5582int sqlite3_value_bytes(sqlite3_value*); 5583int sqlite3_value_bytes16(sqlite3_value*); 5584int sqlite3_value_type(sqlite3_value*); 5585int sqlite3_value_numeric_type(sqlite3_value*); 5586int sqlite3_value_nochange(sqlite3_value*); 5587int sqlite3_value_frombind(sqlite3_value*); 5588 5589/* 5590** CAPI3REF: Finding The Subtype Of SQL Values 5591** METHOD: sqlite3_value 5592** 5593** The sqlite3_value_subtype(V) function returns the subtype for 5594** an [application-defined SQL function] argument V. The subtype 5595** information can be used to pass a limited amount of context from 5596** one SQL function to another. Use the [sqlite3_result_subtype()] 5597** routine to set the subtype for the return value of an SQL function. 5598*/ 5599unsigned int sqlite3_value_subtype(sqlite3_value*); 5600 5601/* 5602** CAPI3REF: Copy And Free SQL Values 5603** METHOD: sqlite3_value 5604** 5605** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5606** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5607** is a [protected sqlite3_value] object even if the input is not. 5608** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5609** memory allocation fails. ^If V is a [pointer value], then the result 5610** of sqlite3_value_dup(V) is a NULL value. 5611** 5612** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5613** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5614** then sqlite3_value_free(V) is a harmless no-op. 5615*/ 5616sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5617void sqlite3_value_free(sqlite3_value*); 5618 5619/* 5620** CAPI3REF: Obtain Aggregate Function Context 5621** METHOD: sqlite3_context 5622** 5623** Implementations of aggregate SQL functions use this 5624** routine to allocate memory for storing their state. 5625** 5626** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5627** for a particular aggregate function, SQLite allocates 5628** N bytes of memory, zeroes out that memory, and returns a pointer 5629** to the new memory. ^On second and subsequent calls to 5630** sqlite3_aggregate_context() for the same aggregate function instance, 5631** the same buffer is returned. Sqlite3_aggregate_context() is normally 5632** called once for each invocation of the xStep callback and then one 5633** last time when the xFinal callback is invoked. ^(When no rows match 5634** an aggregate query, the xStep() callback of the aggregate function 5635** implementation is never called and xFinal() is called exactly once. 5636** In those cases, sqlite3_aggregate_context() might be called for the 5637** first time from within xFinal().)^ 5638** 5639** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5640** when first called if N is less than or equal to zero or if a memory 5641** allocation error occurs. 5642** 5643** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5644** determined by the N parameter on first successful call. Changing the 5645** value of N in any subsequent call to sqlite3_aggregate_context() within 5646** the same aggregate function instance will not resize the memory 5647** allocation.)^ Within the xFinal callback, it is customary to set 5648** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5649** pointless memory allocations occur. 5650** 5651** ^SQLite automatically frees the memory allocated by 5652** sqlite3_aggregate_context() when the aggregate query concludes. 5653** 5654** The first parameter must be a copy of the 5655** [sqlite3_context | SQL function context] that is the first parameter 5656** to the xStep or xFinal callback routine that implements the aggregate 5657** function. 5658** 5659** This routine must be called from the same thread in which 5660** the aggregate SQL function is running. 5661*/ 5662void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5663 5664/* 5665** CAPI3REF: User Data For Functions 5666** METHOD: sqlite3_context 5667** 5668** ^The sqlite3_user_data() interface returns a copy of 5669** the pointer that was the pUserData parameter (the 5th parameter) 5670** of the [sqlite3_create_function()] 5671** and [sqlite3_create_function16()] routines that originally 5672** registered the application defined function. 5673** 5674** This routine must be called from the same thread in which 5675** the application-defined function is running. 5676*/ 5677void *sqlite3_user_data(sqlite3_context*); 5678 5679/* 5680** CAPI3REF: Database Connection For Functions 5681** METHOD: sqlite3_context 5682** 5683** ^The sqlite3_context_db_handle() interface returns a copy of 5684** the pointer to the [database connection] (the 1st parameter) 5685** of the [sqlite3_create_function()] 5686** and [sqlite3_create_function16()] routines that originally 5687** registered the application defined function. 5688*/ 5689sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5690 5691/* 5692** CAPI3REF: Function Auxiliary Data 5693** METHOD: sqlite3_context 5694** 5695** These functions may be used by (non-aggregate) SQL functions to 5696** associate metadata with argument values. If the same value is passed to 5697** multiple invocations of the same SQL function during query execution, under 5698** some circumstances the associated metadata may be preserved. An example 5699** of where this might be useful is in a regular-expression matching 5700** function. The compiled version of the regular expression can be stored as 5701** metadata associated with the pattern string. 5702** Then as long as the pattern string remains the same, 5703** the compiled regular expression can be reused on multiple 5704** invocations of the same function. 5705** 5706** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata 5707** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5708** value to the application-defined function. ^N is zero for the left-most 5709** function argument. ^If there is no metadata 5710** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5711** returns a NULL pointer. 5712** 5713** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 5714** argument of the application-defined function. ^Subsequent 5715** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5716** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 5717** NULL if the metadata has been discarded. 5718** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5719** SQLite will invoke the destructor function X with parameter P exactly 5720** once, when the metadata is discarded. 5721** SQLite is free to discard the metadata at any time, including: <ul> 5722** <li> ^(when the corresponding function parameter changes)^, or 5723** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5724** SQL statement)^, or 5725** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5726** parameter)^, or 5727** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5728** allocation error occurs.)^ </ul> 5729** 5730** Note the last bullet in particular. The destructor X in 5731** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5732** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5733** should be called near the end of the function implementation and the 5734** function implementation should not make any use of P after 5735** sqlite3_set_auxdata() has been called. 5736** 5737** ^(In practice, metadata is preserved between function calls for 5738** function parameters that are compile-time constants, including literal 5739** values and [parameters] and expressions composed from the same.)^ 5740** 5741** The value of the N parameter to these interfaces should be non-negative. 5742** Future enhancements may make use of negative N values to define new 5743** kinds of function caching behavior. 5744** 5745** These routines must be called from the same thread in which 5746** the SQL function is running. 5747*/ 5748void *sqlite3_get_auxdata(sqlite3_context*, int N); 5749void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5750 5751 5752/* 5753** CAPI3REF: Constants Defining Special Destructor Behavior 5754** 5755** These are special values for the destructor that is passed in as the 5756** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 5757** argument is SQLITE_STATIC, it means that the content pointer is constant 5758** and will never change. It does not need to be destroyed. ^The 5759** SQLITE_TRANSIENT value means that the content will likely change in 5760** the near future and that SQLite should make its own private copy of 5761** the content before returning. 5762** 5763** The typedef is necessary to work around problems in certain 5764** C++ compilers. 5765*/ 5766typedef void (*sqlite3_destructor_type)(void*); 5767#define SQLITE_STATIC ((sqlite3_destructor_type)0) 5768#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 5769 5770/* 5771** CAPI3REF: Setting The Result Of An SQL Function 5772** METHOD: sqlite3_context 5773** 5774** These routines are used by the xFunc or xFinal callbacks that 5775** implement SQL functions and aggregates. See 5776** [sqlite3_create_function()] and [sqlite3_create_function16()] 5777** for additional information. 5778** 5779** These functions work very much like the [parameter binding] family of 5780** functions used to bind values to host parameters in prepared statements. 5781** Refer to the [SQL parameter] documentation for additional information. 5782** 5783** ^The sqlite3_result_blob() interface sets the result from 5784** an application-defined function to be the BLOB whose content is pointed 5785** to by the second parameter and which is N bytes long where N is the 5786** third parameter. 5787** 5788** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 5789** interfaces set the result of the application-defined function to be 5790** a BLOB containing all zero bytes and N bytes in size. 5791** 5792** ^The sqlite3_result_double() interface sets the result from 5793** an application-defined function to be a floating point value specified 5794** by its 2nd argument. 5795** 5796** ^The sqlite3_result_error() and sqlite3_result_error16() functions 5797** cause the implemented SQL function to throw an exception. 5798** ^SQLite uses the string pointed to by the 5799** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 5800** as the text of an error message. ^SQLite interprets the error 5801** message string from sqlite3_result_error() as UTF-8. ^SQLite 5802** interprets the string from sqlite3_result_error16() as UTF-16 using 5803** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 5804** ^If the third parameter to sqlite3_result_error() 5805** or sqlite3_result_error16() is negative then SQLite takes as the error 5806** message all text up through the first zero character. 5807** ^If the third parameter to sqlite3_result_error() or 5808** sqlite3_result_error16() is non-negative then SQLite takes that many 5809** bytes (not characters) from the 2nd parameter as the error message. 5810** ^The sqlite3_result_error() and sqlite3_result_error16() 5811** routines make a private copy of the error message text before 5812** they return. Hence, the calling function can deallocate or 5813** modify the text after they return without harm. 5814** ^The sqlite3_result_error_code() function changes the error code 5815** returned by SQLite as a result of an error in a function. ^By default, 5816** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 5817** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 5818** 5819** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 5820** error indicating that a string or BLOB is too long to represent. 5821** 5822** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 5823** error indicating that a memory allocation failed. 5824** 5825** ^The sqlite3_result_int() interface sets the return value 5826** of the application-defined function to be the 32-bit signed integer 5827** value given in the 2nd argument. 5828** ^The sqlite3_result_int64() interface sets the return value 5829** of the application-defined function to be the 64-bit signed integer 5830** value given in the 2nd argument. 5831** 5832** ^The sqlite3_result_null() interface sets the return value 5833** of the application-defined function to be NULL. 5834** 5835** ^The sqlite3_result_text(), sqlite3_result_text16(), 5836** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 5837** set the return value of the application-defined function to be 5838** a text string which is represented as UTF-8, UTF-16 native byte order, 5839** UTF-16 little endian, or UTF-16 big endian, respectively. 5840** ^The sqlite3_result_text64() interface sets the return value of an 5841** application-defined function to be a text string in an encoding 5842** specified by the fifth (and last) parameter, which must be one 5843** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 5844** ^SQLite takes the text result from the application from 5845** the 2nd parameter of the sqlite3_result_text* interfaces. 5846** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5847** is negative, then SQLite takes result text from the 2nd parameter 5848** through the first zero character. 5849** ^If the 3rd parameter to the sqlite3_result_text* interfaces 5850** is non-negative, then as many bytes (not characters) of the text 5851** pointed to by the 2nd parameter are taken as the application-defined 5852** function result. If the 3rd parameter is non-negative, then it 5853** must be the byte offset into the string where the NUL terminator would 5854** appear if the string where NUL terminated. If any NUL characters occur 5855** in the string at a byte offset that is less than the value of the 3rd 5856** parameter, then the resulting string will contain embedded NULs and the 5857** result of expressions operating on strings with embedded NULs is undefined. 5858** ^If the 4th parameter to the sqlite3_result_text* interfaces 5859** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 5860** function as the destructor on the text or BLOB result when it has 5861** finished using that result. 5862** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 5863** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 5864** assumes that the text or BLOB result is in constant space and does not 5865** copy the content of the parameter nor call a destructor on the content 5866** when it has finished using that result. 5867** ^If the 4th parameter to the sqlite3_result_text* interfaces 5868** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 5869** then SQLite makes a copy of the result into space obtained 5870** from [sqlite3_malloc()] before it returns. 5871** 5872** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 5873** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 5874** when the encoding is not UTF8, if the input UTF16 begins with a 5875** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 5876** string and the rest of the string is interpreted according to the 5877** byte-order specified by the BOM. ^The byte-order specified by 5878** the BOM at the beginning of the text overrides the byte-order 5879** specified by the interface procedure. ^So, for example, if 5880** sqlite3_result_text16le() is invoked with text that begins 5881** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 5882** first two bytes of input are skipped and the remaining input 5883** is interpreted as UTF16BE text. 5884** 5885** ^For UTF16 input text to the sqlite3_result_text16(), 5886** sqlite3_result_text16be(), sqlite3_result_text16le(), and 5887** sqlite3_result_text64() routines, if the text contains invalid 5888** UTF16 characters, the invalid characters might be converted 5889** into the unicode replacement character, U+FFFD. 5890** 5891** ^The sqlite3_result_value() interface sets the result of 5892** the application-defined function to be a copy of the 5893** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 5894** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 5895** so that the [sqlite3_value] specified in the parameter may change or 5896** be deallocated after sqlite3_result_value() returns without harm. 5897** ^A [protected sqlite3_value] object may always be used where an 5898** [unprotected sqlite3_value] object is required, so either 5899** kind of [sqlite3_value] object can be used with this interface. 5900** 5901** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 5902** SQL NULL value, just like [sqlite3_result_null(C)], except that it 5903** also associates the host-language pointer P or type T with that 5904** NULL value such that the pointer can be retrieved within an 5905** [application-defined SQL function] using [sqlite3_value_pointer()]. 5906** ^If the D parameter is not NULL, then it is a pointer to a destructor 5907** for the P parameter. ^SQLite invokes D with P as its only argument 5908** when SQLite is finished with P. The T parameter should be a static 5909** string and preferably a string literal. The sqlite3_result_pointer() 5910** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5911** 5912** If these routines are called from within the different thread 5913** than the one containing the application-defined function that received 5914** the [sqlite3_context] pointer, the results are undefined. 5915*/ 5916void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 5917void sqlite3_result_blob64(sqlite3_context*,const void*, 5918 sqlite3_uint64,void(*)(void*)); 5919void sqlite3_result_double(sqlite3_context*, double); 5920void sqlite3_result_error(sqlite3_context*, const char*, int); 5921void sqlite3_result_error16(sqlite3_context*, const void*, int); 5922void sqlite3_result_error_toobig(sqlite3_context*); 5923void sqlite3_result_error_nomem(sqlite3_context*); 5924void sqlite3_result_error_code(sqlite3_context*, int); 5925void sqlite3_result_int(sqlite3_context*, int); 5926void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 5927void sqlite3_result_null(sqlite3_context*); 5928void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 5929void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 5930 void(*)(void*), unsigned char encoding); 5931void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 5932void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 5933void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 5934void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 5935void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 5936void sqlite3_result_zeroblob(sqlite3_context*, int n); 5937int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 5938 5939 5940/* 5941** CAPI3REF: Setting The Subtype Of An SQL Function 5942** METHOD: sqlite3_context 5943** 5944** The sqlite3_result_subtype(C,T) function causes the subtype of 5945** the result from the [application-defined SQL function] with 5946** [sqlite3_context] C to be the value T. Only the lower 8 bits 5947** of the subtype T are preserved in current versions of SQLite; 5948** higher order bits are discarded. 5949** The number of subtype bytes preserved by SQLite might increase 5950** in future releases of SQLite. 5951*/ 5952void sqlite3_result_subtype(sqlite3_context*,unsigned int); 5953 5954/* 5955** CAPI3REF: Define New Collating Sequences 5956** METHOD: sqlite3 5957** 5958** ^These functions add, remove, or modify a [collation] associated 5959** with the [database connection] specified as the first argument. 5960** 5961** ^The name of the collation is a UTF-8 string 5962** for sqlite3_create_collation() and sqlite3_create_collation_v2() 5963** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 5964** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 5965** considered to be the same name. 5966** 5967** ^(The third argument (eTextRep) must be one of the constants: 5968** <ul> 5969** <li> [SQLITE_UTF8], 5970** <li> [SQLITE_UTF16LE], 5971** <li> [SQLITE_UTF16BE], 5972** <li> [SQLITE_UTF16], or 5973** <li> [SQLITE_UTF16_ALIGNED]. 5974** </ul>)^ 5975** ^The eTextRep argument determines the encoding of strings passed 5976** to the collating function callback, xCompare. 5977** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 5978** force strings to be UTF16 with native byte order. 5979** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 5980** on an even byte address. 5981** 5982** ^The fourth argument, pArg, is an application data pointer that is passed 5983** through as the first argument to the collating function callback. 5984** 5985** ^The fifth argument, xCompare, is a pointer to the collating function. 5986** ^Multiple collating functions can be registered using the same name but 5987** with different eTextRep parameters and SQLite will use whichever 5988** function requires the least amount of data transformation. 5989** ^If the xCompare argument is NULL then the collating function is 5990** deleted. ^When all collating functions having the same name are deleted, 5991** that collation is no longer usable. 5992** 5993** ^The collating function callback is invoked with a copy of the pArg 5994** application data pointer and with two strings in the encoding specified 5995** by the eTextRep argument. The two integer parameters to the collating 5996** function callback are the length of the two strings, in bytes. The collating 5997** function must return an integer that is negative, zero, or positive 5998** if the first string is less than, equal to, or greater than the second, 5999** respectively. A collating function must always return the same answer 6000** given the same inputs. If two or more collating functions are registered 6001** to the same collation name (using different eTextRep values) then all 6002** must give an equivalent answer when invoked with equivalent strings. 6003** The collating function must obey the following properties for all 6004** strings A, B, and C: 6005** 6006** <ol> 6007** <li> If A==B then B==A. 6008** <li> If A==B and B==C then A==C. 6009** <li> If A<B THEN B>A. 6010** <li> If A<B and B<C then A<C. 6011** </ol> 6012** 6013** If a collating function fails any of the above constraints and that 6014** collating function is registered and used, then the behavior of SQLite 6015** is undefined. 6016** 6017** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 6018** with the addition that the xDestroy callback is invoked on pArg when 6019** the collating function is deleted. 6020** ^Collating functions are deleted when they are overridden by later 6021** calls to the collation creation functions or when the 6022** [database connection] is closed using [sqlite3_close()]. 6023** 6024** ^The xDestroy callback is <u>not</u> called if the 6025** sqlite3_create_collation_v2() function fails. Applications that invoke 6026** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 6027** check the return code and dispose of the application data pointer 6028** themselves rather than expecting SQLite to deal with it for them. 6029** This is different from every other SQLite interface. The inconsistency 6030** is unfortunate but cannot be changed without breaking backwards 6031** compatibility. 6032** 6033** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 6034*/ 6035int sqlite3_create_collation( 6036 sqlite3*, 6037 const char *zName, 6038 int eTextRep, 6039 void *pArg, 6040 int(*xCompare)(void*,int,const void*,int,const void*) 6041); 6042int sqlite3_create_collation_v2( 6043 sqlite3*, 6044 const char *zName, 6045 int eTextRep, 6046 void *pArg, 6047 int(*xCompare)(void*,int,const void*,int,const void*), 6048 void(*xDestroy)(void*) 6049); 6050int sqlite3_create_collation16( 6051 sqlite3*, 6052 const void *zName, 6053 int eTextRep, 6054 void *pArg, 6055 int(*xCompare)(void*,int,const void*,int,const void*) 6056); 6057 6058/* 6059** CAPI3REF: Collation Needed Callbacks 6060** METHOD: sqlite3 6061** 6062** ^To avoid having to register all collation sequences before a database 6063** can be used, a single callback function may be registered with the 6064** [database connection] to be invoked whenever an undefined collation 6065** sequence is required. 6066** 6067** ^If the function is registered using the sqlite3_collation_needed() API, 6068** then it is passed the names of undefined collation sequences as strings 6069** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 6070** the names are passed as UTF-16 in machine native byte order. 6071** ^A call to either function replaces the existing collation-needed callback. 6072** 6073** ^(When the callback is invoked, the first argument passed is a copy 6074** of the second argument to sqlite3_collation_needed() or 6075** sqlite3_collation_needed16(). The second argument is the database 6076** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 6077** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 6078** sequence function required. The fourth parameter is the name of the 6079** required collation sequence.)^ 6080** 6081** The callback function should register the desired collation using 6082** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 6083** [sqlite3_create_collation_v2()]. 6084*/ 6085int sqlite3_collation_needed( 6086 sqlite3*, 6087 void*, 6088 void(*)(void*,sqlite3*,int eTextRep,const char*) 6089); 6090int sqlite3_collation_needed16( 6091 sqlite3*, 6092 void*, 6093 void(*)(void*,sqlite3*,int eTextRep,const void*) 6094); 6095 6096#ifdef SQLITE_ENABLE_CEROD 6097/* 6098** Specify the activation key for a CEROD database. Unless 6099** activated, none of the CEROD routines will work. 6100*/ 6101void sqlite3_activate_cerod( 6102 const char *zPassPhrase /* Activation phrase */ 6103); 6104#endif 6105 6106/* 6107** CAPI3REF: Suspend Execution For A Short Time 6108** 6109** The sqlite3_sleep() function causes the current thread to suspend execution 6110** for at least a number of milliseconds specified in its parameter. 6111** 6112** If the operating system does not support sleep requests with 6113** millisecond time resolution, then the time will be rounded up to 6114** the nearest second. The number of milliseconds of sleep actually 6115** requested from the operating system is returned. 6116** 6117** ^SQLite implements this interface by calling the xSleep() 6118** method of the default [sqlite3_vfs] object. If the xSleep() method 6119** of the default VFS is not implemented correctly, or not implemented at 6120** all, then the behavior of sqlite3_sleep() may deviate from the description 6121** in the previous paragraphs. 6122*/ 6123int sqlite3_sleep(int); 6124 6125/* 6126** CAPI3REF: Name Of The Folder Holding Temporary Files 6127** 6128** ^(If this global variable is made to point to a string which is 6129** the name of a folder (a.k.a. directory), then all temporary files 6130** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6131** will be placed in that directory.)^ ^If this variable 6132** is a NULL pointer, then SQLite performs a search for an appropriate 6133** temporary file directory. 6134** 6135** Applications are strongly discouraged from using this global variable. 6136** It is required to set a temporary folder on Windows Runtime (WinRT). 6137** But for all other platforms, it is highly recommended that applications 6138** neither read nor write this variable. This global variable is a relic 6139** that exists for backwards compatibility of legacy applications and should 6140** be avoided in new projects. 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 [temp_store_directory pragma] may modify this variable and cause 6152** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6153** the [temp_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 [temp_store_directory pragma] should be avoided. 6160** Except when requested by the [temp_store_directory pragma], SQLite 6161** does not free the memory that sqlite3_temp_directory points to. If 6162** the application wants that memory to be freed, it must do 6163** so itself, taking care to only do so after all [database connection] 6164** objects have been destroyed. 6165** 6166** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6167** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6168** features that require the use of temporary files may fail. Here is an 6169** example of how to do this using C++ with the Windows Runtime: 6170** 6171** <blockquote><pre> 6172** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6173** TemporaryFolder->Path->Data(); 6174** char zPathBuf[MAX_PATH + 1]; 6175** memset(zPathBuf, 0, sizeof(zPathBuf)); 6176** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6177** NULL, NULL); 6178** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6179** </pre></blockquote> 6180*/ 6181SQLITE_EXTERN char *sqlite3_temp_directory; 6182 6183/* 6184** CAPI3REF: Name Of The Folder Holding Database Files 6185** 6186** ^(If this global variable is made to point to a string which is 6187** the name of a folder (a.k.a. directory), then all database files 6188** specified with a relative pathname and created or accessed by 6189** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6190** to be relative to that directory.)^ ^If this variable is a NULL 6191** pointer, then SQLite assumes that all database files specified 6192** with a relative pathname are relative to the current directory 6193** for the process. Only the windows VFS makes use of this global 6194** variable; it is ignored by the unix VFS. 6195** 6196** Changing the value of this variable while a database connection is 6197** open can result in a corrupt database. 6198** 6199** It is not safe to read or modify this variable in more than one 6200** thread at a time. It is not safe to read or modify this variable 6201** if a [database connection] is being used at the same time in a separate 6202** thread. 6203** It is intended that this variable be set once 6204** as part of process initialization and before any SQLite interface 6205** routines have been called and that this variable remain unchanged 6206** thereafter. 6207** 6208** ^The [data_store_directory pragma] may modify this variable and cause 6209** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6210** the [data_store_directory pragma] always assumes that any string 6211** that this variable points to is held in memory obtained from 6212** [sqlite3_malloc] and the pragma may attempt to free that memory 6213** using [sqlite3_free]. 6214** Hence, if this variable is modified directly, either it should be 6215** made NULL or made to point to memory obtained from [sqlite3_malloc] 6216** or else the use of the [data_store_directory pragma] should be avoided. 6217*/ 6218SQLITE_EXTERN char *sqlite3_data_directory; 6219 6220/* 6221** CAPI3REF: Win32 Specific Interface 6222** 6223** These interfaces are available only on Windows. The 6224** [sqlite3_win32_set_directory] interface is used to set the value associated 6225** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6226** zValue, depending on the value of the type parameter. The zValue parameter 6227** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6228** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6229** prior to being used. The [sqlite3_win32_set_directory] interface returns 6230** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6231** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6232** [sqlite3_data_directory] variable is intended to act as a replacement for 6233** the current directory on the sub-platforms of Win32 where that concept is 6234** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6235** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6236** sqlite3_win32_set_directory interface except the string parameter must be 6237** UTF-8 or UTF-16, respectively. 6238*/ 6239int sqlite3_win32_set_directory( 6240 unsigned long type, /* Identifier for directory being set or reset */ 6241 void *zValue /* New value for directory being set or reset */ 6242); 6243int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6244int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6245 6246/* 6247** CAPI3REF: Win32 Directory Types 6248** 6249** These macros are only available on Windows. They define the allowed values 6250** for the type argument to the [sqlite3_win32_set_directory] interface. 6251*/ 6252#define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6253#define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6254 6255/* 6256** CAPI3REF: Test For Auto-Commit Mode 6257** KEYWORDS: {autocommit mode} 6258** METHOD: sqlite3 6259** 6260** ^The sqlite3_get_autocommit() interface returns non-zero or 6261** zero if the given database connection is or is not in autocommit mode, 6262** respectively. ^Autocommit mode is on by default. 6263** ^Autocommit mode is disabled by a [BEGIN] statement. 6264** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6265** 6266** If certain kinds of errors occur on a statement within a multi-statement 6267** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6268** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6269** transaction might be rolled back automatically. The only way to 6270** find out whether SQLite automatically rolled back the transaction after 6271** an error is to use this function. 6272** 6273** If another thread changes the autocommit status of the database 6274** connection while this routine is running, then the return value 6275** is undefined. 6276*/ 6277int sqlite3_get_autocommit(sqlite3*); 6278 6279/* 6280** CAPI3REF: Find The Database Handle Of A Prepared Statement 6281** METHOD: sqlite3_stmt 6282** 6283** ^The sqlite3_db_handle interface returns the [database connection] handle 6284** to which a [prepared statement] belongs. ^The [database connection] 6285** returned by sqlite3_db_handle is the same [database connection] 6286** that was the first argument 6287** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6288** create the statement in the first place. 6289*/ 6290sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6291 6292/* 6293** CAPI3REF: Return The Schema Name For A Database Connection 6294** METHOD: sqlite3 6295** 6296** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name 6297** for the N-th database on database connection D, or a NULL pointer of N is 6298** out of range. An N value of 0 means the main database file. An N of 1 is 6299** the "temp" schema. Larger values of N correspond to various ATTACH-ed 6300** databases. 6301** 6302** Space to hold the string that is returned by sqlite3_db_name() is managed 6303** by SQLite itself. The string might be deallocated by any operation that 6304** changes the schema, including [ATTACH] or [DETACH] or calls to 6305** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that 6306** occur on a different thread. Applications that need to 6307** remember the string long-term should make their own copy. Applications that 6308** are accessing the same database connection simultaneously on multiple 6309** threads should mutex-protect calls to this API and should make their own 6310** private copy of the result prior to releasing the mutex. 6311*/ 6312const char *sqlite3_db_name(sqlite3 *db, int N); 6313 6314/* 6315** CAPI3REF: Return The Filename For A Database Connection 6316** METHOD: sqlite3 6317** 6318** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6319** associated with database N of connection D. 6320** ^If there is no attached database N on the database 6321** connection D, or if database N is a temporary or in-memory database, then 6322** this function will return either a NULL pointer or an empty string. 6323** 6324** ^The string value returned by this routine is owned and managed by 6325** the database connection. ^The value will be valid until the database N 6326** is [DETACH]-ed or until the database connection closes. 6327** 6328** ^The filename returned by this function is the output of the 6329** xFullPathname method of the [VFS]. ^In other words, the filename 6330** will be an absolute pathname, even if the filename used 6331** to open the database originally was a URI or relative pathname. 6332** 6333** If the filename pointer returned by this routine is not NULL, then it 6334** can be used as the filename input parameter to these routines: 6335** <ul> 6336** <li> [sqlite3_uri_parameter()] 6337** <li> [sqlite3_uri_boolean()] 6338** <li> [sqlite3_uri_int64()] 6339** <li> [sqlite3_filename_database()] 6340** <li> [sqlite3_filename_journal()] 6341** <li> [sqlite3_filename_wal()] 6342** </ul> 6343*/ 6344const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6345 6346/* 6347** CAPI3REF: Determine if a database is read-only 6348** METHOD: sqlite3 6349** 6350** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6351** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6352** the name of a database on connection D. 6353*/ 6354int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6355 6356/* 6357** CAPI3REF: Determine the transaction state of a database 6358** METHOD: sqlite3 6359** 6360** ^The sqlite3_txn_state(D,S) interface returns the current 6361** [transaction state] of schema S in database connection D. ^If S is NULL, 6362** then the highest transaction state of any schema on database connection D 6363** is returned. Transaction states are (in order of lowest to highest): 6364** <ol> 6365** <li value="0"> SQLITE_TXN_NONE 6366** <li value="1"> SQLITE_TXN_READ 6367** <li value="2"> SQLITE_TXN_WRITE 6368** </ol> 6369** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 6370** a valid schema, then -1 is returned. 6371*/ 6372int sqlite3_txn_state(sqlite3*,const char *zSchema); 6373 6374/* 6375** CAPI3REF: Allowed return values from [sqlite3_txn_state()] 6376** KEYWORDS: {transaction state} 6377** 6378** These constants define the current transaction state of a database file. 6379** ^The [sqlite3_txn_state(D,S)] interface returns one of these 6380** constants in order to describe the transaction state of schema S 6381** in [database connection] D. 6382** 6383** <dl> 6384** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 6385** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 6386** pending.</dd> 6387** 6388** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 6389** <dd>The SQLITE_TXN_READ state means that the database is currently 6390** in a read transaction. Content has been read from the database file 6391** but nothing in the database file has changed. The transaction state 6392** will advanced to SQLITE_TXN_WRITE if any changes occur and there are 6393** no other conflicting concurrent write transactions. The transaction 6394** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 6395** [COMMIT].</dd> 6396** 6397** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 6398** <dd>The SQLITE_TXN_WRITE state means that the database is currently 6399** in a write transaction. Content has been written to the database file 6400** but has not yet committed. The transaction state will change to 6401** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 6402*/ 6403#define SQLITE_TXN_NONE 0 6404#define SQLITE_TXN_READ 1 6405#define SQLITE_TXN_WRITE 2 6406 6407/* 6408** CAPI3REF: Find the next prepared statement 6409** METHOD: sqlite3 6410** 6411** ^This interface returns a pointer to the next [prepared statement] after 6412** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6413** then this interface returns a pointer to the first prepared statement 6414** associated with the database connection pDb. ^If no prepared statement 6415** satisfies the conditions of this routine, it returns NULL. 6416** 6417** The [database connection] pointer D in a call to 6418** [sqlite3_next_stmt(D,S)] must refer to an open database 6419** connection and in particular must not be a NULL pointer. 6420*/ 6421sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6422 6423/* 6424** CAPI3REF: Commit And Rollback Notification Callbacks 6425** METHOD: sqlite3 6426** 6427** ^The sqlite3_commit_hook() interface registers a callback 6428** function to be invoked whenever a transaction is [COMMIT | committed]. 6429** ^Any callback set by a previous call to sqlite3_commit_hook() 6430** for the same database connection is overridden. 6431** ^The sqlite3_rollback_hook() interface registers a callback 6432** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6433** ^Any callback set by a previous call to sqlite3_rollback_hook() 6434** for the same database connection is overridden. 6435** ^The pArg argument is passed through to the callback. 6436** ^If the callback on a commit hook function returns non-zero, 6437** then the commit is converted into a rollback. 6438** 6439** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6440** return the P argument from the previous call of the same function 6441** on the same [database connection] D, or NULL for 6442** the first call for each function on D. 6443** 6444** The commit and rollback hook callbacks are not reentrant. 6445** The callback implementation must not do anything that will modify 6446** the database connection that invoked the callback. Any actions 6447** to modify the database connection must be deferred until after the 6448** completion of the [sqlite3_step()] call that triggered the commit 6449** or rollback hook in the first place. 6450** Note that running any other SQL statements, including SELECT statements, 6451** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6452** the database connections for the meaning of "modify" in this paragraph. 6453** 6454** ^Registering a NULL function disables the callback. 6455** 6456** ^When the commit hook callback routine returns zero, the [COMMIT] 6457** operation is allowed to continue normally. ^If the commit hook 6458** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6459** ^The rollback hook is invoked on a rollback that results from a commit 6460** hook returning non-zero, just as it would be with any other rollback. 6461** 6462** ^For the purposes of this API, a transaction is said to have been 6463** rolled back if an explicit "ROLLBACK" statement is executed, or 6464** an error or constraint causes an implicit rollback to occur. 6465** ^The rollback callback is not invoked if a transaction is 6466** automatically rolled back because the database connection is closed. 6467** 6468** See also the [sqlite3_update_hook()] interface. 6469*/ 6470void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6471void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6472 6473/* 6474** CAPI3REF: Autovacuum Compaction Amount Callback 6475** METHOD: sqlite3 6476** 6477** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback 6478** function C that is invoked prior to each autovacuum of the database 6479** file. ^The callback is passed a copy of the generic data pointer (P), 6480** the schema-name of the attached database that is being autovacuumed, 6481** the size of the database file in pages, the number of free pages, 6482** and the number of bytes per page, respectively. The callback should 6483** return the number of free pages that should be removed by the 6484** autovacuum. ^If the callback returns zero, then no autovacuum happens. 6485** ^If the value returned is greater than or equal to the number of 6486** free pages, then a complete autovacuum happens. 6487** 6488** <p>^If there are multiple ATTACH-ed database files that are being 6489** modified as part of a transaction commit, then the autovacuum pages 6490** callback is invoked separately for each file. 6491** 6492** <p><b>The callback is not reentrant.</b> The callback function should 6493** not attempt to invoke any other SQLite interface. If it does, bad 6494** things may happen, including segmentation faults and corrupt database 6495** files. The callback function should be a simple function that 6496** does some arithmetic on its input parameters and returns a result. 6497** 6498** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional 6499** destructor for the P parameter. ^If X is not NULL, then X(P) is 6500** invoked whenever the database connection closes or when the callback 6501** is overwritten by another invocation of sqlite3_autovacuum_pages(). 6502** 6503** <p>^There is only one autovacuum pages callback per database connection. 6504** ^Each call to the sqlite3_autovacuum_pages() interface overrides all 6505** previous invocations for that database connection. ^If the callback 6506** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, 6507** then the autovacuum steps callback is cancelled. The return value 6508** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might 6509** be some other error code if something goes wrong. The current 6510** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other 6511** return codes might be added in future releases. 6512** 6513** <p>If no autovacuum pages callback is specified (the usual case) or 6514** a NULL pointer is provided for the callback, 6515** then the default behavior is to vacuum all free pages. So, in other 6516** words, the default behavior is the same as if the callback function 6517** were something like this: 6518** 6519** <blockquote><pre> 6520** unsigned int demonstration_autovac_pages_callback( 6521** void *pClientData, 6522** const char *zSchema, 6523** unsigned int nDbPage, 6524** unsigned int nFreePage, 6525** unsigned int nBytePerPage 6526** ){ 6527** return nFreePage; 6528** } 6529** </pre></blockquote> 6530*/ 6531int sqlite3_autovacuum_pages( 6532 sqlite3 *db, 6533 unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), 6534 void*, 6535 void(*)(void*) 6536); 6537 6538 6539/* 6540** CAPI3REF: Data Change Notification Callbacks 6541** METHOD: sqlite3 6542** 6543** ^The sqlite3_update_hook() interface registers a callback function 6544** with the [database connection] identified by the first argument 6545** to be invoked whenever a row is updated, inserted or deleted in 6546** a [rowid table]. 6547** ^Any callback set by a previous call to this function 6548** for the same database connection is overridden. 6549** 6550** ^The second argument is a pointer to the function to invoke when a 6551** row is updated, inserted or deleted in a rowid table. 6552** ^The first argument to the callback is a copy of the third argument 6553** to sqlite3_update_hook(). 6554** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6555** or [SQLITE_UPDATE], depending on the operation that caused the callback 6556** to be invoked. 6557** ^The third and fourth arguments to the callback contain pointers to the 6558** database and table name containing the affected row. 6559** ^The final callback parameter is the [rowid] of the row. 6560** ^In the case of an update, this is the [rowid] after the update takes place. 6561** 6562** ^(The update hook is not invoked when internal system tables are 6563** modified (i.e. sqlite_sequence).)^ 6564** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6565** 6566** ^In the current implementation, the update hook 6567** is not invoked when conflicting rows are deleted because of an 6568** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6569** invoked when rows are deleted using the [truncate optimization]. 6570** The exceptions defined in this paragraph might change in a future 6571** release of SQLite. 6572** 6573** The update hook implementation must not do anything that will modify 6574** the database connection that invoked the update hook. Any actions 6575** to modify the database connection must be deferred until after the 6576** completion of the [sqlite3_step()] call that triggered the update hook. 6577** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6578** database connections for the meaning of "modify" in this paragraph. 6579** 6580** ^The sqlite3_update_hook(D,C,P) function 6581** returns the P argument from the previous call 6582** on the same [database connection] D, or NULL for 6583** the first call on D. 6584** 6585** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6586** and [sqlite3_preupdate_hook()] interfaces. 6587*/ 6588void *sqlite3_update_hook( 6589 sqlite3*, 6590 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6591 void* 6592); 6593 6594/* 6595** CAPI3REF: Enable Or Disable Shared Pager Cache 6596** 6597** ^(This routine enables or disables the sharing of the database cache 6598** and schema data structures between [database connection | connections] 6599** to the same database. Sharing is enabled if the argument is true 6600** and disabled if the argument is false.)^ 6601** 6602** This interface is omitted if SQLite is compiled with 6603** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] 6604** compile-time option is recommended because the 6605** [use of shared cache mode is discouraged]. 6606** 6607** ^Cache sharing is enabled and disabled for an entire process. 6608** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6609** In prior versions of SQLite, 6610** sharing was enabled or disabled for each thread separately. 6611** 6612** ^(The cache sharing mode set by this interface effects all subsequent 6613** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6614** Existing database connections continue to use the sharing mode 6615** that was in effect at the time they were opened.)^ 6616** 6617** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6618** successfully. An [error code] is returned otherwise.)^ 6619** 6620** ^Shared cache is disabled by default. It is recommended that it stay 6621** that way. In other words, do not use this routine. This interface 6622** continues to be provided for historical compatibility, but its use is 6623** discouraged. Any use of shared cache is discouraged. If shared cache 6624** must be used, it is recommended that shared cache only be enabled for 6625** individual database connections using the [sqlite3_open_v2()] interface 6626** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6627** 6628** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6629** and will always return SQLITE_MISUSE. On those systems, 6630** shared cache mode should be enabled per-database connection via 6631** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6632** 6633** This interface is threadsafe on processors where writing a 6634** 32-bit integer is atomic. 6635** 6636** See Also: [SQLite Shared-Cache Mode] 6637*/ 6638int sqlite3_enable_shared_cache(int); 6639 6640/* 6641** CAPI3REF: Attempt To Free Heap Memory 6642** 6643** ^The sqlite3_release_memory() interface attempts to free N bytes 6644** of heap memory by deallocating non-essential memory allocations 6645** held by the database library. Memory used to cache database 6646** pages to improve performance is an example of non-essential memory. 6647** ^sqlite3_release_memory() returns the number of bytes actually freed, 6648** which might be more or less than the amount requested. 6649** ^The sqlite3_release_memory() routine is a no-op returning zero 6650** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6651** 6652** See also: [sqlite3_db_release_memory()] 6653*/ 6654int sqlite3_release_memory(int); 6655 6656/* 6657** CAPI3REF: Free Memory Used By A Database Connection 6658** METHOD: sqlite3 6659** 6660** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6661** memory as possible from database connection D. Unlike the 6662** [sqlite3_release_memory()] interface, this interface is in effect even 6663** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6664** omitted. 6665** 6666** See also: [sqlite3_release_memory()] 6667*/ 6668int sqlite3_db_release_memory(sqlite3*); 6669 6670/* 6671** CAPI3REF: Impose A Limit On Heap Size 6672** 6673** These interfaces impose limits on the amount of heap memory that will be 6674** by all database connections within a single process. 6675** 6676** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 6677** soft limit on the amount of heap memory that may be allocated by SQLite. 6678** ^SQLite strives to keep heap memory utilization below the soft heap 6679** limit by reducing the number of pages held in the page cache 6680** as heap memory usages approaches the limit. 6681** ^The soft heap limit is "soft" because even though SQLite strives to stay 6682** below the limit, it will exceed the limit rather than generate 6683** an [SQLITE_NOMEM] error. In other words, the soft heap limit 6684** is advisory only. 6685** 6686** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 6687** N bytes on the amount of memory that will be allocated. ^The 6688** sqlite3_hard_heap_limit64(N) interface is similar to 6689** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 6690** when the hard heap limit is reached. 6691** 6692** ^The return value from both sqlite3_soft_heap_limit64() and 6693** sqlite3_hard_heap_limit64() is the size of 6694** the heap limit prior to the call, or negative in the case of an 6695** error. ^If the argument N is negative 6696** then no change is made to the heap limit. Hence, the current 6697** size of heap limits can be determined by invoking 6698** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 6699** 6700** ^Setting the heap limits to zero disables the heap limiter mechanism. 6701** 6702** ^The soft heap limit may not be greater than the hard heap limit. 6703** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 6704** is invoked with a value of N that is greater than the hard heap limit, 6705** the soft heap limit is set to the value of the hard heap limit. 6706** ^The soft heap limit is automatically enabled whenever the hard heap 6707** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 6708** the soft heap limit is outside the range of 1..N, then the soft heap 6709** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 6710** hard heap limit is enabled makes the soft heap limit equal to the 6711** hard heap limit. 6712** 6713** The memory allocation limits can also be adjusted using 6714** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 6715** 6716** ^(The heap limits are not enforced in the current implementation 6717** if one or more of following conditions are true: 6718** 6719** <ul> 6720** <li> The limit value is set to zero. 6721** <li> Memory accounting is disabled using a combination of the 6722** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 6723** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 6724** <li> An alternative page cache implementation is specified using 6725** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 6726** <li> The page cache allocates from its own memory pool supplied 6727** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 6728** from the heap. 6729** </ul>)^ 6730** 6731** The circumstances under which SQLite will enforce the heap limits may 6732** changes in future releases of SQLite. 6733*/ 6734sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 6735sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 6736 6737/* 6738** CAPI3REF: Deprecated Soft Heap Limit Interface 6739** DEPRECATED 6740** 6741** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 6742** interface. This routine is provided for historical compatibility 6743** only. All new applications should use the 6744** [sqlite3_soft_heap_limit64()] interface rather than this one. 6745*/ 6746SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 6747 6748 6749/* 6750** CAPI3REF: Extract Metadata About A Column Of A Table 6751** METHOD: sqlite3 6752** 6753** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 6754** information about column C of table T in database D 6755** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 6756** interface returns SQLITE_OK and fills in the non-NULL pointers in 6757** the final five arguments with appropriate values if the specified 6758** column exists. ^The sqlite3_table_column_metadata() interface returns 6759** SQLITE_ERROR if the specified column does not exist. 6760** ^If the column-name parameter to sqlite3_table_column_metadata() is a 6761** NULL pointer, then this routine simply checks for the existence of the 6762** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 6763** does not. If the table name parameter T in a call to 6764** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 6765** undefined behavior. 6766** 6767** ^The column is identified by the second, third and fourth parameters to 6768** this function. ^(The second parameter is either the name of the database 6769** (i.e. "main", "temp", or an attached database) containing the specified 6770** table or NULL.)^ ^If it is NULL, then all attached databases are searched 6771** for the table using the same algorithm used by the database engine to 6772** resolve unqualified table references. 6773** 6774** ^The third and fourth parameters to this function are the table and column 6775** name of the desired column, respectively. 6776** 6777** ^Metadata is returned by writing to the memory locations passed as the 5th 6778** and subsequent parameters to this function. ^Any of these arguments may be 6779** NULL, in which case the corresponding element of metadata is omitted. 6780** 6781** ^(<blockquote> 6782** <table border="1"> 6783** <tr><th> Parameter <th> Output<br>Type <th> Description 6784** 6785** <tr><td> 5th <td> const char* <td> Data type 6786** <tr><td> 6th <td> const char* <td> Name of default collation sequence 6787** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 6788** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 6789** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 6790** </table> 6791** </blockquote>)^ 6792** 6793** ^The memory pointed to by the character pointers returned for the 6794** declaration type and collation sequence is valid until the next 6795** call to any SQLite API function. 6796** 6797** ^If the specified table is actually a view, an [error code] is returned. 6798** 6799** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 6800** is not a [WITHOUT ROWID] table and an 6801** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 6802** parameters are set for the explicitly declared column. ^(If there is no 6803** [INTEGER PRIMARY KEY] column, then the outputs 6804** for the [rowid] are set as follows: 6805** 6806** <pre> 6807** data type: "INTEGER" 6808** collation sequence: "BINARY" 6809** not null: 0 6810** primary key: 1 6811** auto increment: 0 6812** </pre>)^ 6813** 6814** ^This function causes all database schemas to be read from disk and 6815** parsed, if that has not already been done, and returns an error if 6816** any errors are encountered while loading the schema. 6817*/ 6818int sqlite3_table_column_metadata( 6819 sqlite3 *db, /* Connection handle */ 6820 const char *zDbName, /* Database name or NULL */ 6821 const char *zTableName, /* Table name */ 6822 const char *zColumnName, /* Column name */ 6823 char const **pzDataType, /* OUTPUT: Declared data type */ 6824 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 6825 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 6826 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 6827 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 6828); 6829 6830/* 6831** CAPI3REF: Load An Extension 6832** METHOD: sqlite3 6833** 6834** ^This interface loads an SQLite extension library from the named file. 6835** 6836** ^The sqlite3_load_extension() interface attempts to load an 6837** [SQLite extension] library contained in the file zFile. If 6838** the file cannot be loaded directly, attempts are made to load 6839** with various operating-system specific extensions added. 6840** So for example, if "samplelib" cannot be loaded, then names like 6841** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 6842** be tried also. 6843** 6844** ^The entry point is zProc. 6845** ^(zProc may be 0, in which case SQLite will try to come up with an 6846** entry point name on its own. It first tries "sqlite3_extension_init". 6847** If that does not work, it constructs a name "sqlite3_X_init" where the 6848** X is consists of the lower-case equivalent of all ASCII alphabetic 6849** characters in the filename from the last "/" to the first following 6850** "." and omitting any initial "lib".)^ 6851** ^The sqlite3_load_extension() interface returns 6852** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 6853** ^If an error occurs and pzErrMsg is not 0, then the 6854** [sqlite3_load_extension()] interface shall attempt to 6855** fill *pzErrMsg with error message text stored in memory 6856** obtained from [sqlite3_malloc()]. The calling function 6857** should free this memory by calling [sqlite3_free()]. 6858** 6859** ^Extension loading must be enabled using 6860** [sqlite3_enable_load_extension()] or 6861** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 6862** prior to calling this API, 6863** otherwise an error will be returned. 6864** 6865** <b>Security warning:</b> It is recommended that the 6866** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 6867** interface. The use of the [sqlite3_enable_load_extension()] interface 6868** should be avoided. This will keep the SQL function [load_extension()] 6869** disabled and prevent SQL injections from giving attackers 6870** access to extension loading capabilities. 6871** 6872** See also the [load_extension() SQL function]. 6873*/ 6874int sqlite3_load_extension( 6875 sqlite3 *db, /* Load the extension into this database connection */ 6876 const char *zFile, /* Name of the shared library containing extension */ 6877 const char *zProc, /* Entry point. Derived from zFile if 0 */ 6878 char **pzErrMsg /* Put error message here if not 0 */ 6879); 6880 6881/* 6882** CAPI3REF: Enable Or Disable Extension Loading 6883** METHOD: sqlite3 6884** 6885** ^So as not to open security holes in older applications that are 6886** unprepared to deal with [extension loading], and as a means of disabling 6887** [extension loading] while evaluating user-entered SQL, the following API 6888** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 6889** 6890** ^Extension loading is off by default. 6891** ^Call the sqlite3_enable_load_extension() routine with onoff==1 6892** to turn extension loading on and call it with onoff==0 to turn 6893** it back off again. 6894** 6895** ^This interface enables or disables both the C-API 6896** [sqlite3_load_extension()] and the SQL function [load_extension()]. 6897** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 6898** to enable or disable only the C-API.)^ 6899** 6900** <b>Security warning:</b> It is recommended that extension loading 6901** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 6902** rather than this interface, so the [load_extension()] SQL function 6903** remains disabled. This will prevent SQL injections from giving attackers 6904** access to extension loading capabilities. 6905*/ 6906int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 6907 6908/* 6909** CAPI3REF: Automatically Load Statically Linked Extensions 6910** 6911** ^This interface causes the xEntryPoint() function to be invoked for 6912** each new [database connection] that is created. The idea here is that 6913** xEntryPoint() is the entry point for a statically linked [SQLite extension] 6914** that is to be automatically loaded into all new database connections. 6915** 6916** ^(Even though the function prototype shows that xEntryPoint() takes 6917** no arguments and returns void, SQLite invokes xEntryPoint() with three 6918** arguments and expects an integer result as if the signature of the 6919** entry point where as follows: 6920** 6921** <blockquote><pre> 6922** int xEntryPoint( 6923** sqlite3 *db, 6924** const char **pzErrMsg, 6925** const struct sqlite3_api_routines *pThunk 6926** ); 6927** </pre></blockquote>)^ 6928** 6929** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 6930** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 6931** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 6932** is NULL before calling the xEntryPoint(). ^SQLite will invoke 6933** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 6934** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 6935** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 6936** 6937** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 6938** on the list of automatic extensions is a harmless no-op. ^No entry point 6939** will be called more than once for each database connection that is opened. 6940** 6941** See also: [sqlite3_reset_auto_extension()] 6942** and [sqlite3_cancel_auto_extension()] 6943*/ 6944int sqlite3_auto_extension(void(*xEntryPoint)(void)); 6945 6946/* 6947** CAPI3REF: Cancel Automatic Extension Loading 6948** 6949** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 6950** initialization routine X that was registered using a prior call to 6951** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 6952** routine returns 1 if initialization routine X was successfully 6953** unregistered and it returns 0 if X was not on the list of initialization 6954** routines. 6955*/ 6956int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 6957 6958/* 6959** CAPI3REF: Reset Automatic Extension Loading 6960** 6961** ^This interface disables all automatic extensions previously 6962** registered using [sqlite3_auto_extension()]. 6963*/ 6964void sqlite3_reset_auto_extension(void); 6965 6966/* 6967** The interface to the virtual-table mechanism is currently considered 6968** to be experimental. The interface might change in incompatible ways. 6969** If this is a problem for you, do not use the interface at this time. 6970** 6971** When the virtual-table mechanism stabilizes, we will declare the 6972** interface fixed, support it indefinitely, and remove this comment. 6973*/ 6974 6975/* 6976** Structures used by the virtual table interface 6977*/ 6978typedef struct sqlite3_vtab sqlite3_vtab; 6979typedef struct sqlite3_index_info sqlite3_index_info; 6980typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 6981typedef struct sqlite3_module sqlite3_module; 6982 6983/* 6984** CAPI3REF: Virtual Table Object 6985** KEYWORDS: sqlite3_module {virtual table module} 6986** 6987** This structure, sometimes called a "virtual table module", 6988** defines the implementation of a [virtual table]. 6989** This structure consists mostly of methods for the module. 6990** 6991** ^A virtual table module is created by filling in a persistent 6992** instance of this structure and passing a pointer to that instance 6993** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 6994** ^The registration remains valid until it is replaced by a different 6995** module or until the [database connection] closes. The content 6996** of this structure must not change while it is registered with 6997** any database connection. 6998*/ 6999struct sqlite3_module { 7000 int iVersion; 7001 int (*xCreate)(sqlite3*, void *pAux, 7002 int argc, const char *const*argv, 7003 sqlite3_vtab **ppVTab, char**); 7004 int (*xConnect)(sqlite3*, void *pAux, 7005 int argc, const char *const*argv, 7006 sqlite3_vtab **ppVTab, char**); 7007 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 7008 int (*xDisconnect)(sqlite3_vtab *pVTab); 7009 int (*xDestroy)(sqlite3_vtab *pVTab); 7010 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 7011 int (*xClose)(sqlite3_vtab_cursor*); 7012 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 7013 int argc, sqlite3_value **argv); 7014 int (*xNext)(sqlite3_vtab_cursor*); 7015 int (*xEof)(sqlite3_vtab_cursor*); 7016 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 7017 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 7018 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 7019 int (*xBegin)(sqlite3_vtab *pVTab); 7020 int (*xSync)(sqlite3_vtab *pVTab); 7021 int (*xCommit)(sqlite3_vtab *pVTab); 7022 int (*xRollback)(sqlite3_vtab *pVTab); 7023 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 7024 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 7025 void **ppArg); 7026 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 7027 /* The methods above are in version 1 of the sqlite_module object. Those 7028 ** below are for version 2 and greater. */ 7029 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 7030 int (*xRelease)(sqlite3_vtab *pVTab, int); 7031 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 7032 /* The methods above are in versions 1 and 2 of the sqlite_module object. 7033 ** Those below are for version 3 and greater. */ 7034 int (*xShadowName)(const char*); 7035}; 7036 7037/* 7038** CAPI3REF: Virtual Table Indexing Information 7039** KEYWORDS: sqlite3_index_info 7040** 7041** The sqlite3_index_info structure and its substructures is used as part 7042** of the [virtual table] interface to 7043** pass information into and receive the reply from the [xBestIndex] 7044** method of a [virtual table module]. The fields under **Inputs** are the 7045** inputs to xBestIndex and are read-only. xBestIndex inserts its 7046** results into the **Outputs** fields. 7047** 7048** ^(The aConstraint[] array records WHERE clause constraints of the form: 7049** 7050** <blockquote>column OP expr</blockquote> 7051** 7052** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 7053** stored in aConstraint[].op using one of the 7054** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 7055** ^(The index of the column is stored in 7056** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 7057** expr on the right-hand side can be evaluated (and thus the constraint 7058** is usable) and false if it cannot.)^ 7059** 7060** ^The optimizer automatically inverts terms of the form "expr OP column" 7061** and makes other simplifications to the WHERE clause in an attempt to 7062** get as many WHERE clause terms into the form shown above as possible. 7063** ^The aConstraint[] array only reports WHERE clause terms that are 7064** relevant to the particular virtual table being queried. 7065** 7066** ^Information about the ORDER BY clause is stored in aOrderBy[]. 7067** ^Each term of aOrderBy records a column of the ORDER BY clause. 7068** 7069** The colUsed field indicates which columns of the virtual table may be 7070** required by the current scan. Virtual table columns are numbered from 7071** zero in the order in which they appear within the CREATE TABLE statement 7072** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 7073** the corresponding bit is set within the colUsed mask if the column may be 7074** required by SQLite. If the table has at least 64 columns and any column 7075** to the right of the first 63 is required, then bit 63 of colUsed is also 7076** set. In other words, column iCol may be required if the expression 7077** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 7078** non-zero. 7079** 7080** The [xBestIndex] method must fill aConstraintUsage[] with information 7081** about what parameters to pass to xFilter. ^If argvIndex>0 then 7082** the right-hand side of the corresponding aConstraint[] is evaluated 7083** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 7084** is true, then the constraint is assumed to be fully handled by the 7085** virtual table and might not be checked again by the byte code.)^ ^(The 7086** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 7087** is left in its default setting of false, the constraint will always be 7088** checked separately in byte code. If the omit flag is change to true, then 7089** the constraint may or may not be checked in byte code. In other words, 7090** when the omit flag is true there is no guarantee that the constraint will 7091** not be checked again using byte code.)^ 7092** 7093** ^The idxNum and idxPtr values are recorded and passed into the 7094** [xFilter] method. 7095** ^[sqlite3_free()] is used to free idxPtr if and only if 7096** needToFreeIdxPtr is true. 7097** 7098** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 7099** the correct order to satisfy the ORDER BY clause so that no separate 7100** sorting step is required. 7101** 7102** ^The estimatedCost value is an estimate of the cost of a particular 7103** strategy. A cost of N indicates that the cost of the strategy is similar 7104** to a linear scan of an SQLite table with N rows. A cost of log(N) 7105** indicates that the expense of the operation is similar to that of a 7106** binary search on a unique indexed field of an SQLite table with N rows. 7107** 7108** ^The estimatedRows value is an estimate of the number of rows that 7109** will be returned by the strategy. 7110** 7111** The xBestIndex method may optionally populate the idxFlags field with a 7112** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 7113** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 7114** assumes that the strategy may visit at most one row. 7115** 7116** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 7117** SQLite also assumes that if a call to the xUpdate() method is made as 7118** part of the same statement to delete or update a virtual table row and the 7119** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 7120** any database changes. In other words, if the xUpdate() returns 7121** SQLITE_CONSTRAINT, the database contents must be exactly as they were 7122** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 7123** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 7124** the xUpdate method are automatically rolled back by SQLite. 7125** 7126** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 7127** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 7128** If a virtual table extension is 7129** used with an SQLite version earlier than 3.8.2, the results of attempting 7130** to read or write the estimatedRows field are undefined (but are likely 7131** to include crashing the application). The estimatedRows field should 7132** therefore only be used if [sqlite3_libversion_number()] returns a 7133** value greater than or equal to 3008002. Similarly, the idxFlags field 7134** was added for [version 3.9.0] ([dateof:3.9.0]). 7135** It may therefore only be used if 7136** sqlite3_libversion_number() returns a value greater than or equal to 7137** 3009000. 7138*/ 7139struct sqlite3_index_info { 7140 /* Inputs */ 7141 int nConstraint; /* Number of entries in aConstraint */ 7142 struct sqlite3_index_constraint { 7143 int iColumn; /* Column constrained. -1 for ROWID */ 7144 unsigned char op; /* Constraint operator */ 7145 unsigned char usable; /* True if this constraint is usable */ 7146 int iTermOffset; /* Used internally - xBestIndex should ignore */ 7147 } *aConstraint; /* Table of WHERE clause constraints */ 7148 int nOrderBy; /* Number of terms in the ORDER BY clause */ 7149 struct sqlite3_index_orderby { 7150 int iColumn; /* Column number */ 7151 unsigned char desc; /* True for DESC. False for ASC. */ 7152 } *aOrderBy; /* The ORDER BY clause */ 7153 /* Outputs */ 7154 struct sqlite3_index_constraint_usage { 7155 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 7156 unsigned char omit; /* Do not code a test for this constraint */ 7157 } *aConstraintUsage; 7158 int idxNum; /* Number used to identify the index */ 7159 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 7160 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 7161 int orderByConsumed; /* True if output is already ordered */ 7162 double estimatedCost; /* Estimated cost of using this index */ 7163 /* Fields below are only available in SQLite 3.8.2 and later */ 7164 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 7165 /* Fields below are only available in SQLite 3.9.0 and later */ 7166 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 7167 /* Fields below are only available in SQLite 3.10.0 and later */ 7168 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 7169}; 7170 7171/* 7172** CAPI3REF: Virtual Table Scan Flags 7173** 7174** Virtual table implementations are allowed to set the 7175** [sqlite3_index_info].idxFlags field to some combination of 7176** these bits. 7177*/ 7178#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 7179 7180/* 7181** CAPI3REF: Virtual Table Constraint Operator Codes 7182** 7183** These macros define the allowed values for the 7184** [sqlite3_index_info].aConstraint[].op field. Each value represents 7185** an operator that is part of a constraint term in the WHERE clause of 7186** a query that uses a [virtual table]. 7187** 7188** ^The left-hand operand of the operator is given by the corresponding 7189** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand 7190** operand is the rowid. 7191** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET 7192** operators have no left-hand operand, and so for those operators the 7193** corresponding aConstraint[].iColumn is meaningless and should not be 7194** used. 7195** 7196** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through 7197** value 255 are reserved to represent functions that are overloaded 7198** by the [xFindFunction|xFindFunction method] of the virtual table 7199** implementation. 7200** 7201** The right-hand operands for each constraint might be accessible using 7202** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand 7203** operand is only available if it appears as a single constant literal 7204** in the input SQL. If the right-hand operand is another column or an 7205** expression (even a constant expression) or a parameter, then the 7206** sqlite3_vtab_rhs_value() probably will not be able to extract it. 7207** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and 7208** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand 7209** and hence calls to sqlite3_vtab_rhs_value() for those operators will 7210** always return SQLITE_NOTFOUND. 7211** 7212** The collating sequence to be used for comparison can be found using 7213** the [sqlite3_vtab_collation()] interface. For most real-world virtual 7214** tables, the collating sequence of constraints does not matter (for example 7215** because the constraints are numeric) and so the sqlite3_vtab_collation() 7216** interface is no commonly needed. 7217*/ 7218#define SQLITE_INDEX_CONSTRAINT_EQ 2 7219#define SQLITE_INDEX_CONSTRAINT_GT 4 7220#define SQLITE_INDEX_CONSTRAINT_LE 8 7221#define SQLITE_INDEX_CONSTRAINT_LT 16 7222#define SQLITE_INDEX_CONSTRAINT_GE 32 7223#define SQLITE_INDEX_CONSTRAINT_MATCH 64 7224#define SQLITE_INDEX_CONSTRAINT_LIKE 65 7225#define SQLITE_INDEX_CONSTRAINT_GLOB 66 7226#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 7227#define SQLITE_INDEX_CONSTRAINT_NE 68 7228#define SQLITE_INDEX_CONSTRAINT_ISNOT 69 7229#define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 7230#define SQLITE_INDEX_CONSTRAINT_ISNULL 71 7231#define SQLITE_INDEX_CONSTRAINT_IS 72 7232#define SQLITE_INDEX_CONSTRAINT_LIMIT 73 7233#define SQLITE_INDEX_CONSTRAINT_OFFSET 74 7234#define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 7235 7236/* 7237** CAPI3REF: Register A Virtual Table Implementation 7238** METHOD: sqlite3 7239** 7240** ^These routines are used to register a new [virtual table module] name. 7241** ^Module names must be registered before 7242** creating a new [virtual table] using the module and before using a 7243** preexisting [virtual table] for the module. 7244** 7245** ^The module name is registered on the [database connection] specified 7246** by the first parameter. ^The name of the module is given by the 7247** second parameter. ^The third parameter is a pointer to 7248** the implementation of the [virtual table module]. ^The fourth 7249** parameter is an arbitrary client data pointer that is passed through 7250** into the [xCreate] and [xConnect] methods of the virtual table module 7251** when a new virtual table is be being created or reinitialized. 7252** 7253** ^The sqlite3_create_module_v2() interface has a fifth parameter which 7254** is a pointer to a destructor for the pClientData. ^SQLite will 7255** invoke the destructor function (if it is not NULL) when SQLite 7256** no longer needs the pClientData pointer. ^The destructor will also 7257** be invoked if the call to sqlite3_create_module_v2() fails. 7258** ^The sqlite3_create_module() 7259** interface is equivalent to sqlite3_create_module_v2() with a NULL 7260** destructor. 7261** 7262** ^If the third parameter (the pointer to the sqlite3_module object) is 7263** NULL then no new module is created and any existing modules with the 7264** same name are dropped. 7265** 7266** See also: [sqlite3_drop_modules()] 7267*/ 7268int sqlite3_create_module( 7269 sqlite3 *db, /* SQLite connection to register module with */ 7270 const char *zName, /* Name of the module */ 7271 const sqlite3_module *p, /* Methods for the module */ 7272 void *pClientData /* Client data for xCreate/xConnect */ 7273); 7274int sqlite3_create_module_v2( 7275 sqlite3 *db, /* SQLite connection to register module with */ 7276 const char *zName, /* Name of the module */ 7277 const sqlite3_module *p, /* Methods for the module */ 7278 void *pClientData, /* Client data for xCreate/xConnect */ 7279 void(*xDestroy)(void*) /* Module destructor function */ 7280); 7281 7282/* 7283** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7284** METHOD: sqlite3 7285** 7286** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7287** table modules from database connection D except those named on list L. 7288** The L parameter must be either NULL or a pointer to an array of pointers 7289** to strings where the array is terminated by a single NULL pointer. 7290** ^If the L parameter is NULL, then all virtual table modules are removed. 7291** 7292** See also: [sqlite3_create_module()] 7293*/ 7294int sqlite3_drop_modules( 7295 sqlite3 *db, /* Remove modules from this connection */ 7296 const char **azKeep /* Except, do not remove the ones named here */ 7297); 7298 7299/* 7300** CAPI3REF: Virtual Table Instance Object 7301** KEYWORDS: sqlite3_vtab 7302** 7303** Every [virtual table module] implementation uses a subclass 7304** of this object to describe a particular instance 7305** of the [virtual table]. Each subclass will 7306** be tailored to the specific needs of the module implementation. 7307** The purpose of this superclass is to define certain fields that are 7308** common to all module implementations. 7309** 7310** ^Virtual tables methods can set an error message by assigning a 7311** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 7312** take care that any prior string is freed by a call to [sqlite3_free()] 7313** prior to assigning a new string to zErrMsg. ^After the error message 7314** is delivered up to the client application, the string will be automatically 7315** freed by sqlite3_free() and the zErrMsg field will be zeroed. 7316*/ 7317struct sqlite3_vtab { 7318 const sqlite3_module *pModule; /* The module for this virtual table */ 7319 int nRef; /* Number of open cursors */ 7320 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 7321 /* Virtual table implementations will typically add additional fields */ 7322}; 7323 7324/* 7325** CAPI3REF: Virtual Table Cursor Object 7326** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 7327** 7328** Every [virtual table module] implementation uses a subclass of the 7329** following structure to describe cursors that point into the 7330** [virtual table] and are used 7331** to loop through the virtual table. Cursors are created using the 7332** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 7333** by the [sqlite3_module.xClose | xClose] method. Cursors are used 7334** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 7335** of the module. Each module implementation will define 7336** the content of a cursor structure to suit its own needs. 7337** 7338** This superclass exists in order to define fields of the cursor that 7339** are common to all implementations. 7340*/ 7341struct sqlite3_vtab_cursor { 7342 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 7343 /* Virtual table implementations will typically add additional fields */ 7344}; 7345 7346/* 7347** CAPI3REF: Declare The Schema Of A Virtual Table 7348** 7349** ^The [xCreate] and [xConnect] methods of a 7350** [virtual table module] call this interface 7351** to declare the format (the names and datatypes of the columns) of 7352** the virtual tables they implement. 7353*/ 7354int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 7355 7356/* 7357** CAPI3REF: Overload A Function For A Virtual Table 7358** METHOD: sqlite3 7359** 7360** ^(Virtual tables can provide alternative implementations of functions 7361** using the [xFindFunction] method of the [virtual table module]. 7362** But global versions of those functions 7363** must exist in order to be overloaded.)^ 7364** 7365** ^(This API makes sure a global version of a function with a particular 7366** name and number of parameters exists. If no such function exists 7367** before this API is called, a new function is created.)^ ^The implementation 7368** of the new function always causes an exception to be thrown. So 7369** the new function is not good for anything by itself. Its only 7370** purpose is to be a placeholder function that can be overloaded 7371** by a [virtual table]. 7372*/ 7373int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 7374 7375/* 7376** The interface to the virtual-table mechanism defined above (back up 7377** to a comment remarkably similar to this one) is currently considered 7378** to be experimental. The interface might change in incompatible ways. 7379** If this is a problem for you, do not use the interface at this time. 7380** 7381** When the virtual-table mechanism stabilizes, we will declare the 7382** interface fixed, support it indefinitely, and remove this comment. 7383*/ 7384 7385/* 7386** CAPI3REF: A Handle To An Open BLOB 7387** KEYWORDS: {BLOB handle} {BLOB handles} 7388** 7389** An instance of this object represents an open BLOB on which 7390** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 7391** ^Objects of this type are created by [sqlite3_blob_open()] 7392** and destroyed by [sqlite3_blob_close()]. 7393** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 7394** can be used to read or write small subsections of the BLOB. 7395** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 7396*/ 7397typedef struct sqlite3_blob sqlite3_blob; 7398 7399/* 7400** CAPI3REF: Open A BLOB For Incremental I/O 7401** METHOD: sqlite3 7402** CONSTRUCTOR: sqlite3_blob 7403** 7404** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 7405** in row iRow, column zColumn, table zTable in database zDb; 7406** in other words, the same BLOB that would be selected by: 7407** 7408** <pre> 7409** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7410** </pre>)^ 7411** 7412** ^(Parameter zDb is not the filename that contains the database, but 7413** rather the symbolic name of the database. For attached databases, this is 7414** the name that appears after the AS keyword in the [ATTACH] statement. 7415** For the main database file, the database name is "main". For TEMP 7416** tables, the database name is "temp".)^ 7417** 7418** ^If the flags parameter is non-zero, then the BLOB is opened for read 7419** and write access. ^If the flags parameter is zero, the BLOB is opened for 7420** read-only access. 7421** 7422** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7423** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7424** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7425** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7426** on *ppBlob after this function it returns. 7427** 7428** This function fails with SQLITE_ERROR if any of the following are true: 7429** <ul> 7430** <li> ^(Database zDb does not exist)^, 7431** <li> ^(Table zTable does not exist within database zDb)^, 7432** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7433** <li> ^(Column zColumn does not exist)^, 7434** <li> ^(Row iRow is not present in the table)^, 7435** <li> ^(The specified column of row iRow contains a value that is not 7436** a TEXT or BLOB value)^, 7437** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7438** constraint and the blob is being opened for read/write access)^, 7439** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7440** column zColumn is part of a [child key] definition and the blob is 7441** being opened for read/write access)^. 7442** </ul> 7443** 7444** ^Unless it returns SQLITE_MISUSE, this function sets the 7445** [database connection] error code and message accessible via 7446** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7447** 7448** A BLOB referenced by sqlite3_blob_open() may be read using the 7449** [sqlite3_blob_read()] interface and modified by using 7450** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7451** different row of the same table using the [sqlite3_blob_reopen()] 7452** interface. However, the column, table, or database of a [BLOB handle] 7453** cannot be changed after the [BLOB handle] is opened. 7454** 7455** ^(If the row that a BLOB handle points to is modified by an 7456** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7457** then the BLOB handle is marked as "expired". 7458** This is true if any column of the row is changed, even a column 7459** other than the one the BLOB handle is open on.)^ 7460** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7461** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7462** ^(Changes written into a BLOB prior to the BLOB expiring are not 7463** rolled back by the expiration of the BLOB. Such changes will eventually 7464** commit if the transaction continues to completion.)^ 7465** 7466** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7467** the opened blob. ^The size of a blob may not be changed by this 7468** interface. Use the [UPDATE] SQL command to change the size of a 7469** blob. 7470** 7471** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7472** and the built-in [zeroblob] SQL function may be used to create a 7473** zero-filled blob to read or write using the incremental-blob interface. 7474** 7475** To avoid a resource leak, every open [BLOB handle] should eventually 7476** be released by a call to [sqlite3_blob_close()]. 7477** 7478** See also: [sqlite3_blob_close()], 7479** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7480** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7481*/ 7482int sqlite3_blob_open( 7483 sqlite3*, 7484 const char *zDb, 7485 const char *zTable, 7486 const char *zColumn, 7487 sqlite3_int64 iRow, 7488 int flags, 7489 sqlite3_blob **ppBlob 7490); 7491 7492/* 7493** CAPI3REF: Move a BLOB Handle to a New Row 7494** METHOD: sqlite3_blob 7495** 7496** ^This function is used to move an existing [BLOB handle] so that it points 7497** to a different row of the same database table. ^The new row is identified 7498** by the rowid value passed as the second argument. Only the row can be 7499** changed. ^The database, table and column on which the blob handle is open 7500** remain the same. Moving an existing [BLOB handle] to a new row is 7501** faster than closing the existing handle and opening a new one. 7502** 7503** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7504** it must exist and there must be either a blob or text value stored in 7505** the nominated column.)^ ^If the new row is not present in the table, or if 7506** it does not contain a blob or text value, or if another error occurs, an 7507** SQLite error code is returned and the blob handle is considered aborted. 7508** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7509** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7510** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7511** always returns zero. 7512** 7513** ^This function sets the database handle error code and message. 7514*/ 7515int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7516 7517/* 7518** CAPI3REF: Close A BLOB Handle 7519** DESTRUCTOR: sqlite3_blob 7520** 7521** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7522** unconditionally. Even if this routine returns an error code, the 7523** handle is still closed.)^ 7524** 7525** ^If the blob handle being closed was opened for read-write access, and if 7526** the database is in auto-commit mode and there are no other open read-write 7527** blob handles or active write statements, the current transaction is 7528** committed. ^If an error occurs while committing the transaction, an error 7529** code is returned and the transaction rolled back. 7530** 7531** Calling this function with an argument that is not a NULL pointer or an 7532** open blob handle results in undefined behaviour. ^Calling this routine 7533** with a null pointer (such as would be returned by a failed call to 7534** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7535** is passed a valid open blob handle, the values returned by the 7536** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7537*/ 7538int sqlite3_blob_close(sqlite3_blob *); 7539 7540/* 7541** CAPI3REF: Return The Size Of An Open BLOB 7542** METHOD: sqlite3_blob 7543** 7544** ^Returns the size in bytes of the BLOB accessible via the 7545** successfully opened [BLOB handle] in its only argument. ^The 7546** incremental blob I/O routines can only read or overwriting existing 7547** blob content; they cannot change the size of a blob. 7548** 7549** This routine only works on a [BLOB handle] which has been created 7550** by a prior successful call to [sqlite3_blob_open()] and which has not 7551** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7552** to this routine results in undefined and probably undesirable behavior. 7553*/ 7554int sqlite3_blob_bytes(sqlite3_blob *); 7555 7556/* 7557** CAPI3REF: Read Data From A BLOB Incrementally 7558** METHOD: sqlite3_blob 7559** 7560** ^(This function is used to read data from an open [BLOB handle] into a 7561** caller-supplied buffer. N bytes of data are copied into buffer Z 7562** from the open BLOB, starting at offset iOffset.)^ 7563** 7564** ^If offset iOffset is less than N bytes from the end of the BLOB, 7565** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7566** less than zero, [SQLITE_ERROR] is returned and no data is read. 7567** ^The size of the blob (and hence the maximum value of N+iOffset) 7568** can be determined using the [sqlite3_blob_bytes()] interface. 7569** 7570** ^An attempt to read from an expired [BLOB handle] fails with an 7571** error code of [SQLITE_ABORT]. 7572** 7573** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7574** Otherwise, an [error code] or an [extended error code] is returned.)^ 7575** 7576** This routine only works on a [BLOB handle] which has been created 7577** by a prior successful call to [sqlite3_blob_open()] and which has not 7578** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7579** to this routine results in undefined and probably undesirable behavior. 7580** 7581** See also: [sqlite3_blob_write()]. 7582*/ 7583int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7584 7585/* 7586** CAPI3REF: Write Data Into A BLOB Incrementally 7587** METHOD: sqlite3_blob 7588** 7589** ^(This function is used to write data into an open [BLOB handle] from a 7590** caller-supplied buffer. N bytes of data are copied from the buffer Z 7591** into the open BLOB, starting at offset iOffset.)^ 7592** 7593** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7594** Otherwise, an [error code] or an [extended error code] is returned.)^ 7595** ^Unless SQLITE_MISUSE is returned, this function sets the 7596** [database connection] error code and message accessible via 7597** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7598** 7599** ^If the [BLOB handle] passed as the first argument was not opened for 7600** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7601** this function returns [SQLITE_READONLY]. 7602** 7603** This function may only modify the contents of the BLOB; it is 7604** not possible to increase the size of a BLOB using this API. 7605** ^If offset iOffset is less than N bytes from the end of the BLOB, 7606** [SQLITE_ERROR] is returned and no data is written. The size of the 7607** BLOB (and hence the maximum value of N+iOffset) can be determined 7608** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7609** than zero [SQLITE_ERROR] is returned and no data is written. 7610** 7611** ^An attempt to write to an expired [BLOB handle] fails with an 7612** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7613** before the [BLOB handle] expired are not rolled back by the 7614** expiration of the handle, though of course those changes might 7615** have been overwritten by the statement that expired the BLOB handle 7616** or by other independent statements. 7617** 7618** This routine only works on a [BLOB handle] which has been created 7619** by a prior successful call to [sqlite3_blob_open()] and which has not 7620** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7621** to this routine results in undefined and probably undesirable behavior. 7622** 7623** See also: [sqlite3_blob_read()]. 7624*/ 7625int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7626 7627/* 7628** CAPI3REF: Virtual File System Objects 7629** 7630** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7631** that SQLite uses to interact 7632** with the underlying operating system. Most SQLite builds come with a 7633** single default VFS that is appropriate for the host computer. 7634** New VFSes can be registered and existing VFSes can be unregistered. 7635** The following interfaces are provided. 7636** 7637** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7638** ^Names are case sensitive. 7639** ^Names are zero-terminated UTF-8 strings. 7640** ^If there is no match, a NULL pointer is returned. 7641** ^If zVfsName is NULL then the default VFS is returned. 7642** 7643** ^New VFSes are registered with sqlite3_vfs_register(). 7644** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7645** ^The same VFS can be registered multiple times without injury. 7646** ^To make an existing VFS into the default VFS, register it again 7647** with the makeDflt flag set. If two different VFSes with the 7648** same name are registered, the behavior is undefined. If a 7649** VFS is registered with a name that is NULL or an empty string, 7650** then the behavior is undefined. 7651** 7652** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7653** ^(If the default VFS is unregistered, another VFS is chosen as 7654** the default. The choice for the new VFS is arbitrary.)^ 7655*/ 7656sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7657int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7658int sqlite3_vfs_unregister(sqlite3_vfs*); 7659 7660/* 7661** CAPI3REF: Mutexes 7662** 7663** The SQLite core uses these routines for thread 7664** synchronization. Though they are intended for internal 7665** use by SQLite, code that links against SQLite is 7666** permitted to use any of these routines. 7667** 7668** The SQLite source code contains multiple implementations 7669** of these mutex routines. An appropriate implementation 7670** is selected automatically at compile-time. The following 7671** implementations are available in the SQLite core: 7672** 7673** <ul> 7674** <li> SQLITE_MUTEX_PTHREADS 7675** <li> SQLITE_MUTEX_W32 7676** <li> SQLITE_MUTEX_NOOP 7677** </ul> 7678** 7679** The SQLITE_MUTEX_NOOP implementation is a set of routines 7680** that does no real locking and is appropriate for use in 7681** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7682** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7683** and Windows. 7684** 7685** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7686** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7687** implementation is included with the library. In this case the 7688** application must supply a custom mutex implementation using the 7689** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7690** before calling sqlite3_initialize() or any other public sqlite3_ 7691** function that calls sqlite3_initialize(). 7692** 7693** ^The sqlite3_mutex_alloc() routine allocates a new 7694** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 7695** routine returns NULL if it is unable to allocate the requested 7696** mutex. The argument to sqlite3_mutex_alloc() must one of these 7697** integer constants: 7698** 7699** <ul> 7700** <li> SQLITE_MUTEX_FAST 7701** <li> SQLITE_MUTEX_RECURSIVE 7702** <li> SQLITE_MUTEX_STATIC_MAIN 7703** <li> SQLITE_MUTEX_STATIC_MEM 7704** <li> SQLITE_MUTEX_STATIC_OPEN 7705** <li> SQLITE_MUTEX_STATIC_PRNG 7706** <li> SQLITE_MUTEX_STATIC_LRU 7707** <li> SQLITE_MUTEX_STATIC_PMEM 7708** <li> SQLITE_MUTEX_STATIC_APP1 7709** <li> SQLITE_MUTEX_STATIC_APP2 7710** <li> SQLITE_MUTEX_STATIC_APP3 7711** <li> SQLITE_MUTEX_STATIC_VFS1 7712** <li> SQLITE_MUTEX_STATIC_VFS2 7713** <li> SQLITE_MUTEX_STATIC_VFS3 7714** </ul> 7715** 7716** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 7717** cause sqlite3_mutex_alloc() to create 7718** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 7719** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 7720** The mutex implementation does not need to make a distinction 7721** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 7722** not want to. SQLite will only request a recursive mutex in 7723** cases where it really needs one. If a faster non-recursive mutex 7724** implementation is available on the host platform, the mutex subsystem 7725** might return such a mutex in response to SQLITE_MUTEX_FAST. 7726** 7727** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 7728** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 7729** a pointer to a static preexisting mutex. ^Nine static mutexes are 7730** used by the current version of SQLite. Future versions of SQLite 7731** may add additional static mutexes. Static mutexes are for internal 7732** use by SQLite only. Applications that use SQLite mutexes should 7733** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 7734** SQLITE_MUTEX_RECURSIVE. 7735** 7736** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 7737** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 7738** returns a different mutex on every call. ^For the static 7739** mutex types, the same mutex is returned on every call that has 7740** the same type number. 7741** 7742** ^The sqlite3_mutex_free() routine deallocates a previously 7743** allocated dynamic mutex. Attempting to deallocate a static 7744** mutex results in undefined behavior. 7745** 7746** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 7747** to enter a mutex. ^If another thread is already within the mutex, 7748** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 7749** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 7750** upon successful entry. ^(Mutexes created using 7751** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 7752** In such cases, the 7753** mutex must be exited an equal number of times before another thread 7754** can enter.)^ If the same thread tries to enter any mutex other 7755** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 7756** 7757** ^(Some systems (for example, Windows 95) do not support the operation 7758** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 7759** will always return SQLITE_BUSY. The SQLite core only ever uses 7760** sqlite3_mutex_try() as an optimization so this is acceptable 7761** behavior.)^ 7762** 7763** ^The sqlite3_mutex_leave() routine exits a mutex that was 7764** previously entered by the same thread. The behavior 7765** is undefined if the mutex is not currently entered by the 7766** calling thread or is not currently allocated. 7767** 7768** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 7769** sqlite3_mutex_leave() is a NULL pointer, then all three routines 7770** behave as no-ops. 7771** 7772** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 7773*/ 7774sqlite3_mutex *sqlite3_mutex_alloc(int); 7775void sqlite3_mutex_free(sqlite3_mutex*); 7776void sqlite3_mutex_enter(sqlite3_mutex*); 7777int sqlite3_mutex_try(sqlite3_mutex*); 7778void sqlite3_mutex_leave(sqlite3_mutex*); 7779 7780/* 7781** CAPI3REF: Mutex Methods Object 7782** 7783** An instance of this structure defines the low-level routines 7784** used to allocate and use mutexes. 7785** 7786** Usually, the default mutex implementations provided by SQLite are 7787** sufficient, however the application has the option of substituting a custom 7788** implementation for specialized deployments or systems for which SQLite 7789** does not provide a suitable implementation. In this case, the application 7790** creates and populates an instance of this structure to pass 7791** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 7792** Additionally, an instance of this structure can be used as an 7793** output variable when querying the system for the current mutex 7794** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 7795** 7796** ^The xMutexInit method defined by this structure is invoked as 7797** part of system initialization by the sqlite3_initialize() function. 7798** ^The xMutexInit routine is called by SQLite exactly once for each 7799** effective call to [sqlite3_initialize()]. 7800** 7801** ^The xMutexEnd method defined by this structure is invoked as 7802** part of system shutdown by the sqlite3_shutdown() function. The 7803** implementation of this method is expected to release all outstanding 7804** resources obtained by the mutex methods implementation, especially 7805** those obtained by the xMutexInit method. ^The xMutexEnd() 7806** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 7807** 7808** ^(The remaining seven methods defined by this structure (xMutexAlloc, 7809** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 7810** xMutexNotheld) implement the following interfaces (respectively): 7811** 7812** <ul> 7813** <li> [sqlite3_mutex_alloc()] </li> 7814** <li> [sqlite3_mutex_free()] </li> 7815** <li> [sqlite3_mutex_enter()] </li> 7816** <li> [sqlite3_mutex_try()] </li> 7817** <li> [sqlite3_mutex_leave()] </li> 7818** <li> [sqlite3_mutex_held()] </li> 7819** <li> [sqlite3_mutex_notheld()] </li> 7820** </ul>)^ 7821** 7822** The only difference is that the public sqlite3_XXX functions enumerated 7823** above silently ignore any invocations that pass a NULL pointer instead 7824** of a valid mutex handle. The implementations of the methods defined 7825** by this structure are not required to handle this case. The results 7826** of passing a NULL pointer instead of a valid mutex handle are undefined 7827** (i.e. it is acceptable to provide an implementation that segfaults if 7828** it is passed a NULL pointer). 7829** 7830** The xMutexInit() method must be threadsafe. It must be harmless to 7831** invoke xMutexInit() multiple times within the same process and without 7832** intervening calls to xMutexEnd(). Second and subsequent calls to 7833** xMutexInit() must be no-ops. 7834** 7835** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 7836** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 7837** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 7838** memory allocation for a fast or recursive mutex. 7839** 7840** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 7841** called, but only if the prior call to xMutexInit returned SQLITE_OK. 7842** If xMutexInit fails in any way, it is expected to clean up after itself 7843** prior to returning. 7844*/ 7845typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 7846struct sqlite3_mutex_methods { 7847 int (*xMutexInit)(void); 7848 int (*xMutexEnd)(void); 7849 sqlite3_mutex *(*xMutexAlloc)(int); 7850 void (*xMutexFree)(sqlite3_mutex *); 7851 void (*xMutexEnter)(sqlite3_mutex *); 7852 int (*xMutexTry)(sqlite3_mutex *); 7853 void (*xMutexLeave)(sqlite3_mutex *); 7854 int (*xMutexHeld)(sqlite3_mutex *); 7855 int (*xMutexNotheld)(sqlite3_mutex *); 7856}; 7857 7858/* 7859** CAPI3REF: Mutex Verification Routines 7860** 7861** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 7862** are intended for use inside assert() statements. The SQLite core 7863** never uses these routines except inside an assert() and applications 7864** are advised to follow the lead of the core. The SQLite core only 7865** provides implementations for these routines when it is compiled 7866** with the SQLITE_DEBUG flag. External mutex implementations 7867** are only required to provide these routines if SQLITE_DEBUG is 7868** defined and if NDEBUG is not defined. 7869** 7870** These routines should return true if the mutex in their argument 7871** is held or not held, respectively, by the calling thread. 7872** 7873** The implementation is not required to provide versions of these 7874** routines that actually work. If the implementation does not provide working 7875** versions of these routines, it should at least provide stubs that always 7876** return true so that one does not get spurious assertion failures. 7877** 7878** If the argument to sqlite3_mutex_held() is a NULL pointer then 7879** the routine should return 1. This seems counter-intuitive since 7880** clearly the mutex cannot be held if it does not exist. But 7881** the reason the mutex does not exist is because the build is not 7882** using mutexes. And we do not want the assert() containing the 7883** call to sqlite3_mutex_held() to fail, so a non-zero return is 7884** the appropriate thing to do. The sqlite3_mutex_notheld() 7885** interface should also return 1 when given a NULL pointer. 7886*/ 7887#ifndef NDEBUG 7888int sqlite3_mutex_held(sqlite3_mutex*); 7889int sqlite3_mutex_notheld(sqlite3_mutex*); 7890#endif 7891 7892/* 7893** CAPI3REF: Mutex Types 7894** 7895** The [sqlite3_mutex_alloc()] interface takes a single argument 7896** which is one of these integer constants. 7897** 7898** The set of static mutexes may change from one SQLite release to the 7899** next. Applications that override the built-in mutex logic must be 7900** prepared to accommodate additional static mutexes. 7901*/ 7902#define SQLITE_MUTEX_FAST 0 7903#define SQLITE_MUTEX_RECURSIVE 1 7904#define SQLITE_MUTEX_STATIC_MAIN 2 7905#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 7906#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 7907#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 7908#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 7909#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 7910#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 7911#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 7912#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 7913#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 7914#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 7915#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 7916#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 7917#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 7918 7919/* Legacy compatibility: */ 7920#define SQLITE_MUTEX_STATIC_MASTER 2 7921 7922 7923/* 7924** CAPI3REF: Retrieve the mutex for a database connection 7925** METHOD: sqlite3 7926** 7927** ^This interface returns a pointer the [sqlite3_mutex] object that 7928** serializes access to the [database connection] given in the argument 7929** when the [threading mode] is Serialized. 7930** ^If the [threading mode] is Single-thread or Multi-thread then this 7931** routine returns a NULL pointer. 7932*/ 7933sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 7934 7935/* 7936** CAPI3REF: Low-Level Control Of Database Files 7937** METHOD: sqlite3 7938** KEYWORDS: {file control} 7939** 7940** ^The [sqlite3_file_control()] interface makes a direct call to the 7941** xFileControl method for the [sqlite3_io_methods] object associated 7942** with a particular database identified by the second argument. ^The 7943** name of the database is "main" for the main database or "temp" for the 7944** TEMP database, or the name that appears after the AS keyword for 7945** databases that are added using the [ATTACH] SQL command. 7946** ^A NULL pointer can be used in place of "main" to refer to the 7947** main database file. 7948** ^The third and fourth parameters to this routine 7949** are passed directly through to the second and third parameters of 7950** the xFileControl method. ^The return value of the xFileControl 7951** method becomes the return value of this routine. 7952** 7953** A few opcodes for [sqlite3_file_control()] are handled directly 7954** by the SQLite core and never invoke the 7955** sqlite3_io_methods.xFileControl method. 7956** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 7957** a pointer to the underlying [sqlite3_file] object to be written into 7958** the space pointed to by the 4th parameter. The 7959** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 7960** the [sqlite3_file] object associated with the journal file instead of 7961** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 7962** a pointer to the underlying [sqlite3_vfs] object for the file. 7963** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 7964** from the pager. 7965** 7966** ^If the second parameter (zDbName) does not match the name of any 7967** open database file, then SQLITE_ERROR is returned. ^This error 7968** code is not remembered and will not be recalled by [sqlite3_errcode()] 7969** or [sqlite3_errmsg()]. The underlying xFileControl method might 7970** also return SQLITE_ERROR. There is no way to distinguish between 7971** an incorrect zDbName and an SQLITE_ERROR return from the underlying 7972** xFileControl method. 7973** 7974** See also: [file control opcodes] 7975*/ 7976int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 7977 7978/* 7979** CAPI3REF: Testing Interface 7980** 7981** ^The sqlite3_test_control() interface is used to read out internal 7982** state of SQLite and to inject faults into SQLite for testing 7983** purposes. ^The first parameter is an operation code that determines 7984** the number, meaning, and operation of all subsequent parameters. 7985** 7986** This interface is not for use by applications. It exists solely 7987** for verifying the correct operation of the SQLite library. Depending 7988** on how the SQLite library is compiled, this interface might not exist. 7989** 7990** The details of the operation codes, their meanings, the parameters 7991** they take, and what they do are all subject to change without notice. 7992** Unlike most of the SQLite API, this function is not guaranteed to 7993** operate consistently from one release to the next. 7994*/ 7995int sqlite3_test_control(int op, ...); 7996 7997/* 7998** CAPI3REF: Testing Interface Operation Codes 7999** 8000** These constants are the valid operation code parameters used 8001** as the first argument to [sqlite3_test_control()]. 8002** 8003** These parameters and their meanings are subject to change 8004** without notice. These values are for testing purposes only. 8005** Applications should not use any of these parameters or the 8006** [sqlite3_test_control()] interface. 8007*/ 8008#define SQLITE_TESTCTRL_FIRST 5 8009#define SQLITE_TESTCTRL_PRNG_SAVE 5 8010#define SQLITE_TESTCTRL_PRNG_RESTORE 6 8011#define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 8012#define SQLITE_TESTCTRL_BITVEC_TEST 8 8013#define SQLITE_TESTCTRL_FAULT_INSTALL 9 8014#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 8015#define SQLITE_TESTCTRL_PENDING_BYTE 11 8016#define SQLITE_TESTCTRL_ASSERT 12 8017#define SQLITE_TESTCTRL_ALWAYS 13 8018#define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 8019#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 8020#define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 8021#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 8022#define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 8023#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 8024#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 8025#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 8026#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 8027#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 8028#define SQLITE_TESTCTRL_BYTEORDER 22 8029#define SQLITE_TESTCTRL_ISINIT 23 8030#define SQLITE_TESTCTRL_SORTER_MMAP 24 8031#define SQLITE_TESTCTRL_IMPOSTER 25 8032#define SQLITE_TESTCTRL_PARSER_COVERAGE 26 8033#define SQLITE_TESTCTRL_RESULT_INTREAL 27 8034#define SQLITE_TESTCTRL_PRNG_SEED 28 8035#define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 8036#define SQLITE_TESTCTRL_SEEK_COUNT 30 8037#define SQLITE_TESTCTRL_TRACEFLAGS 31 8038#define SQLITE_TESTCTRL_TUNE 32 8039#define SQLITE_TESTCTRL_LOGEST 33 8040#define SQLITE_TESTCTRL_LAST 33 /* Largest TESTCTRL */ 8041 8042/* 8043** CAPI3REF: SQL Keyword Checking 8044** 8045** These routines provide access to the set of SQL language keywords 8046** recognized by SQLite. Applications can uses these routines to determine 8047** whether or not a specific identifier needs to be escaped (for example, 8048** by enclosing in double-quotes) so as not to confuse the parser. 8049** 8050** The sqlite3_keyword_count() interface returns the number of distinct 8051** keywords understood by SQLite. 8052** 8053** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and 8054** makes *Z point to that keyword expressed as UTF8 and writes the number 8055** of bytes in the keyword into *L. The string that *Z points to is not 8056** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 8057** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 8058** or L are NULL or invalid pointers then calls to 8059** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 8060** 8061** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 8062** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 8063** if it is and zero if not. 8064** 8065** The parser used by SQLite is forgiving. It is often possible to use 8066** a keyword as an identifier as long as such use does not result in a 8067** parsing ambiguity. For example, the statement 8068** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 8069** creates a new table named "BEGIN" with three columns named 8070** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 8071** using keywords as identifiers. Common techniques used to avoid keyword 8072** name collisions include: 8073** <ul> 8074** <li> Put all identifier names inside double-quotes. This is the official 8075** SQL way to escape identifier names. 8076** <li> Put identifier names inside [...]. This is not standard SQL, 8077** but it is what SQL Server does and so lots of programmers use this 8078** technique. 8079** <li> Begin every identifier with the letter "Z" as no SQL keywords start 8080** with "Z". 8081** <li> Include a digit somewhere in every identifier name. 8082** </ul> 8083** 8084** Note that the number of keywords understood by SQLite can depend on 8085** compile-time options. For example, "VACUUM" is not a keyword if 8086** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 8087** new keywords may be added to future releases of SQLite. 8088*/ 8089int sqlite3_keyword_count(void); 8090int sqlite3_keyword_name(int,const char**,int*); 8091int sqlite3_keyword_check(const char*,int); 8092 8093/* 8094** CAPI3REF: Dynamic String Object 8095** KEYWORDS: {dynamic string} 8096** 8097** An instance of the sqlite3_str object contains a dynamically-sized 8098** string under construction. 8099** 8100** The lifecycle of an sqlite3_str object is as follows: 8101** <ol> 8102** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 8103** <li> ^Text is appended to the sqlite3_str object using various 8104** methods, such as [sqlite3_str_appendf()]. 8105** <li> ^The sqlite3_str object is destroyed and the string it created 8106** is returned using the [sqlite3_str_finish()] interface. 8107** </ol> 8108*/ 8109typedef struct sqlite3_str sqlite3_str; 8110 8111/* 8112** CAPI3REF: Create A New Dynamic String Object 8113** CONSTRUCTOR: sqlite3_str 8114** 8115** ^The [sqlite3_str_new(D)] interface allocates and initializes 8116** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 8117** [sqlite3_str_new()] must be freed by a subsequent call to 8118** [sqlite3_str_finish(X)]. 8119** 8120** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 8121** valid [sqlite3_str] object, though in the event of an out-of-memory 8122** error the returned object might be a special singleton that will 8123** silently reject new text, always return SQLITE_NOMEM from 8124** [sqlite3_str_errcode()], always return 0 for 8125** [sqlite3_str_length()], and always return NULL from 8126** [sqlite3_str_finish(X)]. It is always safe to use the value 8127** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 8128** to any of the other [sqlite3_str] methods. 8129** 8130** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 8131** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 8132** length of the string contained in the [sqlite3_str] object will be 8133** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 8134** of [SQLITE_MAX_LENGTH]. 8135*/ 8136sqlite3_str *sqlite3_str_new(sqlite3*); 8137 8138/* 8139** CAPI3REF: Finalize A Dynamic String 8140** DESTRUCTOR: sqlite3_str 8141** 8142** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 8143** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 8144** that contains the constructed string. The calling application should 8145** pass the returned value to [sqlite3_free()] to avoid a memory leak. 8146** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 8147** errors were encountered during construction of the string. ^The 8148** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 8149** string in [sqlite3_str] object X is zero bytes long. 8150*/ 8151char *sqlite3_str_finish(sqlite3_str*); 8152 8153/* 8154** CAPI3REF: Add Content To A Dynamic String 8155** METHOD: sqlite3_str 8156** 8157** These interfaces add content to an sqlite3_str object previously obtained 8158** from [sqlite3_str_new()]. 8159** 8160** ^The [sqlite3_str_appendf(X,F,...)] and 8161** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 8162** functionality of SQLite to append formatted text onto the end of 8163** [sqlite3_str] object X. 8164** 8165** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 8166** onto the end of the [sqlite3_str] object X. N must be non-negative. 8167** S must contain at least N non-zero bytes of content. To append a 8168** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 8169** method instead. 8170** 8171** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 8172** zero-terminated string S onto the end of [sqlite3_str] object X. 8173** 8174** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 8175** single-byte character C onto the end of [sqlite3_str] object X. 8176** ^This method can be used, for example, to add whitespace indentation. 8177** 8178** ^The [sqlite3_str_reset(X)] method resets the string under construction 8179** inside [sqlite3_str] object X back to zero bytes in length. 8180** 8181** These methods do not return a result code. ^If an error occurs, that fact 8182** is recorded in the [sqlite3_str] object and can be recovered by a 8183** subsequent call to [sqlite3_str_errcode(X)]. 8184*/ 8185void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 8186void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 8187void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 8188void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 8189void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 8190void sqlite3_str_reset(sqlite3_str*); 8191 8192/* 8193** CAPI3REF: Status Of A Dynamic String 8194** METHOD: sqlite3_str 8195** 8196** These interfaces return the current status of an [sqlite3_str] object. 8197** 8198** ^If any prior errors have occurred while constructing the dynamic string 8199** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 8200** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 8201** [SQLITE_NOMEM] following any out-of-memory error, or 8202** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 8203** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 8204** 8205** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 8206** of the dynamic string under construction in [sqlite3_str] object X. 8207** ^The length returned by [sqlite3_str_length(X)] does not include the 8208** zero-termination byte. 8209** 8210** ^The [sqlite3_str_value(X)] method returns a pointer to the current 8211** content of the dynamic string under construction in X. The value 8212** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 8213** and might be freed or altered by any subsequent method on the same 8214** [sqlite3_str] object. Applications must not used the pointer returned 8215** [sqlite3_str_value(X)] after any subsequent method call on the same 8216** object. ^Applications may change the content of the string returned 8217** by [sqlite3_str_value(X)] as long as they do not write into any bytes 8218** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 8219** write any byte after any subsequent sqlite3_str method call. 8220*/ 8221int sqlite3_str_errcode(sqlite3_str*); 8222int sqlite3_str_length(sqlite3_str*); 8223char *sqlite3_str_value(sqlite3_str*); 8224 8225/* 8226** CAPI3REF: SQLite Runtime Status 8227** 8228** ^These interfaces are used to retrieve runtime status information 8229** about the performance of SQLite, and optionally to reset various 8230** highwater marks. ^The first argument is an integer code for 8231** the specific parameter to measure. ^(Recognized integer codes 8232** are of the form [status parameters | SQLITE_STATUS_...].)^ 8233** ^The current value of the parameter is returned into *pCurrent. 8234** ^The highest recorded value is returned in *pHighwater. ^If the 8235** resetFlag is true, then the highest record value is reset after 8236** *pHighwater is written. ^(Some parameters do not record the highest 8237** value. For those parameters 8238** nothing is written into *pHighwater and the resetFlag is ignored.)^ 8239** ^(Other parameters record only the highwater mark and not the current 8240** value. For these latter parameters nothing is written into *pCurrent.)^ 8241** 8242** ^The sqlite3_status() and sqlite3_status64() routines return 8243** SQLITE_OK on success and a non-zero [error code] on failure. 8244** 8245** If either the current value or the highwater mark is too large to 8246** be represented by a 32-bit integer, then the values returned by 8247** sqlite3_status() are undefined. 8248** 8249** See also: [sqlite3_db_status()] 8250*/ 8251int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 8252int sqlite3_status64( 8253 int op, 8254 sqlite3_int64 *pCurrent, 8255 sqlite3_int64 *pHighwater, 8256 int resetFlag 8257); 8258 8259 8260/* 8261** CAPI3REF: Status Parameters 8262** KEYWORDS: {status parameters} 8263** 8264** These integer constants designate various run-time status parameters 8265** that can be returned by [sqlite3_status()]. 8266** 8267** <dl> 8268** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8269** <dd>This parameter is the current amount of memory checked out 8270** using [sqlite3_malloc()], either directly or indirectly. The 8271** figure includes calls made to [sqlite3_malloc()] by the application 8272** and internal memory usage by the SQLite library. Auxiliary page-cache 8273** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8274** this parameter. The amount returned is the sum of the allocation 8275** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8276** 8277** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8278** <dd>This parameter records the largest memory allocation request 8279** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8280** internal equivalents). Only the value returned in the 8281** *pHighwater parameter to [sqlite3_status()] is of interest. 8282** The value written into the *pCurrent parameter is undefined.</dd>)^ 8283** 8284** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8285** <dd>This parameter records the number of separate memory allocations 8286** currently checked out.</dd>)^ 8287** 8288** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8289** <dd>This parameter returns the number of pages used out of the 8290** [pagecache memory allocator] that was configured using 8291** [SQLITE_CONFIG_PAGECACHE]. The 8292** value returned is in pages, not in bytes.</dd>)^ 8293** 8294** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8295** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8296** <dd>This parameter returns the number of bytes of page cache 8297** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8298** buffer and where forced to overflow to [sqlite3_malloc()]. The 8299** returned value includes allocations that overflowed because they 8300** where too large (they were larger than the "sz" parameter to 8301** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8302** no space was left in the page cache.</dd>)^ 8303** 8304** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 8305** <dd>This parameter records the largest memory allocation request 8306** handed to the [pagecache memory allocator]. Only the value returned in the 8307** *pHighwater parameter to [sqlite3_status()] is of interest. 8308** The value written into the *pCurrent parameter is undefined.</dd>)^ 8309** 8310** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 8311** <dd>No longer used.</dd> 8312** 8313** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 8314** <dd>No longer used.</dd> 8315** 8316** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 8317** <dd>No longer used.</dd> 8318** 8319** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 8320** <dd>The *pHighwater parameter records the deepest parser stack. 8321** The *pCurrent value is undefined. The *pHighwater value is only 8322** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 8323** </dl> 8324** 8325** New status parameters may be added from time to time. 8326*/ 8327#define SQLITE_STATUS_MEMORY_USED 0 8328#define SQLITE_STATUS_PAGECACHE_USED 1 8329#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 8330#define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 8331#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 8332#define SQLITE_STATUS_MALLOC_SIZE 5 8333#define SQLITE_STATUS_PARSER_STACK 6 8334#define SQLITE_STATUS_PAGECACHE_SIZE 7 8335#define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 8336#define SQLITE_STATUS_MALLOC_COUNT 9 8337 8338/* 8339** CAPI3REF: Database Connection Status 8340** METHOD: sqlite3 8341** 8342** ^This interface is used to retrieve runtime status information 8343** about a single [database connection]. ^The first argument is the 8344** database connection object to be interrogated. ^The second argument 8345** is an integer constant, taken from the set of 8346** [SQLITE_DBSTATUS options], that 8347** determines the parameter to interrogate. The set of 8348** [SQLITE_DBSTATUS options] is likely 8349** to grow in future releases of SQLite. 8350** 8351** ^The current value of the requested parameter is written into *pCur 8352** and the highest instantaneous value is written into *pHiwtr. ^If 8353** the resetFlg is true, then the highest instantaneous value is 8354** reset back down to the current value. 8355** 8356** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 8357** non-zero [error code] on failure. 8358** 8359** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 8360*/ 8361int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 8362 8363/* 8364** CAPI3REF: Status Parameters for database connections 8365** KEYWORDS: {SQLITE_DBSTATUS options} 8366** 8367** These constants are the available integer "verbs" that can be passed as 8368** the second argument to the [sqlite3_db_status()] interface. 8369** 8370** New verbs may be added in future releases of SQLite. Existing verbs 8371** might be discontinued. Applications should check the return code from 8372** [sqlite3_db_status()] to make sure that the call worked. 8373** The [sqlite3_db_status()] interface will return a non-zero error code 8374** if a discontinued or unsupported verb is invoked. 8375** 8376** <dl> 8377** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 8378** <dd>This parameter returns the number of lookaside memory slots currently 8379** checked out.</dd>)^ 8380** 8381** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 8382** <dd>This parameter returns the number of malloc attempts that were 8383** satisfied using lookaside memory. Only the high-water value is meaningful; 8384** the current value is always zero.)^ 8385** 8386** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 8387** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 8388** <dd>This parameter returns the number malloc attempts that might have 8389** been satisfied using lookaside memory but failed due to the amount of 8390** memory requested being larger than the lookaside slot size. 8391** Only the high-water value is meaningful; 8392** the current value is always zero.)^ 8393** 8394** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 8395** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 8396** <dd>This parameter returns the number malloc attempts that might have 8397** been satisfied using lookaside memory but failed due to all lookaside 8398** memory already being in use. 8399** Only the high-water value is meaningful; 8400** the current value is always zero.)^ 8401** 8402** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 8403** <dd>This parameter returns the approximate number of bytes of heap 8404** memory used by all pager caches associated with the database connection.)^ 8405** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 8406** 8407** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 8408** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 8409** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 8410** pager cache is shared between two or more connections the bytes of heap 8411** memory used by that pager cache is divided evenly between the attached 8412** connections.)^ In other words, if none of the pager caches associated 8413** with the database connection are shared, this request returns the same 8414** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8415** shared, the value returned by this call will be smaller than that returned 8416** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8417** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8418** 8419** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8420** <dd>This parameter returns the approximate number of bytes of heap 8421** memory used to store the schema for all databases associated 8422** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8423** ^The full amount of memory used by the schemas is reported, even if the 8424** schema memory is shared with other database connections due to 8425** [shared cache mode] being enabled. 8426** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8427** 8428** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8429** <dd>This parameter returns the approximate number of bytes of heap 8430** and lookaside memory used by all prepared statements associated with 8431** the database connection.)^ 8432** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8433** </dd> 8434** 8435** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8436** <dd>This parameter returns the number of pager cache hits that have 8437** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8438** is always 0. 8439** </dd> 8440** 8441** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8442** <dd>This parameter returns the number of pager cache misses that have 8443** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8444** is always 0. 8445** </dd> 8446** 8447** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8448** <dd>This parameter returns the number of dirty cache entries that have 8449** been written to disk. Specifically, the number of pages written to the 8450** wal file in wal mode databases, or the number of pages written to the 8451** database file in rollback mode databases. Any pages written as part of 8452** transaction rollback or database recovery operations are not included. 8453** If an IO or other error occurs while writing a page to disk, the effect 8454** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8455** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8456** </dd> 8457** 8458** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8459** <dd>This parameter returns the number of dirty cache entries that have 8460** been written to disk in the middle of a transaction due to the page 8461** cache overflowing. Transactions are more efficient if they are written 8462** to disk all at once. When pages spill mid-transaction, that introduces 8463** additional overhead. This parameter can be used help identify 8464** inefficiencies that can be resolved by increasing the cache size. 8465** </dd> 8466** 8467** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8468** <dd>This parameter returns zero for the current value if and only if 8469** all foreign key constraints (deferred or immediate) have been 8470** resolved.)^ ^The highwater mark is always 0. 8471** </dd> 8472** </dl> 8473*/ 8474#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8475#define SQLITE_DBSTATUS_CACHE_USED 1 8476#define SQLITE_DBSTATUS_SCHEMA_USED 2 8477#define SQLITE_DBSTATUS_STMT_USED 3 8478#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8479#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8480#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8481#define SQLITE_DBSTATUS_CACHE_HIT 7 8482#define SQLITE_DBSTATUS_CACHE_MISS 8 8483#define SQLITE_DBSTATUS_CACHE_WRITE 9 8484#define SQLITE_DBSTATUS_DEFERRED_FKS 10 8485#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8486#define SQLITE_DBSTATUS_CACHE_SPILL 12 8487#define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8488 8489 8490/* 8491** CAPI3REF: Prepared Statement Status 8492** METHOD: sqlite3_stmt 8493** 8494** ^(Each prepared statement maintains various 8495** [SQLITE_STMTSTATUS counters] that measure the number 8496** of times it has performed specific operations.)^ These counters can 8497** be used to monitor the performance characteristics of the prepared 8498** statements. For example, if the number of table steps greatly exceeds 8499** the number of table searches or result rows, that would tend to indicate 8500** that the prepared statement is using a full table scan rather than 8501** an index. 8502** 8503** ^(This interface is used to retrieve and reset counter values from 8504** a [prepared statement]. The first argument is the prepared statement 8505** object to be interrogated. The second argument 8506** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8507** to be interrogated.)^ 8508** ^The current value of the requested counter is returned. 8509** ^If the resetFlg is true, then the counter is reset to zero after this 8510** interface call returns. 8511** 8512** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8513*/ 8514int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8515 8516/* 8517** CAPI3REF: Status Parameters for prepared statements 8518** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8519** 8520** These preprocessor macros define integer codes that name counter 8521** values associated with the [sqlite3_stmt_status()] interface. 8522** The meanings of the various counters are as follows: 8523** 8524** <dl> 8525** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8526** <dd>^This is the number of times that SQLite has stepped forward in 8527** a table as part of a full table scan. Large numbers for this counter 8528** may indicate opportunities for performance improvement through 8529** careful use of indices.</dd> 8530** 8531** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8532** <dd>^This is the number of sort operations that have occurred. 8533** A non-zero value in this counter may indicate an opportunity to 8534** improvement performance through careful use of indices.</dd> 8535** 8536** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8537** <dd>^This is the number of rows inserted into transient indices that 8538** were created automatically in order to help joins run faster. 8539** A non-zero value in this counter may indicate an opportunity to 8540** improvement performance by adding permanent indices that do not 8541** need to be reinitialized each time the statement is run.</dd> 8542** 8543** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8544** <dd>^This is the number of virtual machine operations executed 8545** by the prepared statement if that number is less than or equal 8546** to 2147483647. The number of virtual machine operations can be 8547** used as a proxy for the total work done by the prepared statement. 8548** If the number of virtual machine operations exceeds 2147483647 8549** then the value returned by this statement status code is undefined. 8550** 8551** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8552** <dd>^This is the number of times that the prepare statement has been 8553** automatically regenerated due to schema changes or changes to 8554** [bound parameters] that might affect the query plan. 8555** 8556** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8557** <dd>^This is the number of times that the prepared statement has 8558** been run. A single "run" for the purposes of this counter is one 8559** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8560** The counter is incremented on the first [sqlite3_step()] call of each 8561** cycle. 8562** 8563** [[SQLITE_STMTSTATUS_FILTER_MISS]] 8564** [[SQLITE_STMTSTATUS_FILTER HIT]] 8565** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br> 8566** SQLITE_STMTSTATUS_FILTER_MISS</dt> 8567** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join 8568** step was bypassed because a Bloom filter returned not-found. The 8569** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of 8570** times that the Bloom filter returned a find, and thus the join step 8571** had to be processed as normal. 8572** 8573** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8574** <dd>^This is the approximate number of bytes of heap memory 8575** used to store the prepared statement. ^This value is not actually 8576** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8577** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8578** </dd> 8579** </dl> 8580*/ 8581#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8582#define SQLITE_STMTSTATUS_SORT 2 8583#define SQLITE_STMTSTATUS_AUTOINDEX 3 8584#define SQLITE_STMTSTATUS_VM_STEP 4 8585#define SQLITE_STMTSTATUS_REPREPARE 5 8586#define SQLITE_STMTSTATUS_RUN 6 8587#define SQLITE_STMTSTATUS_FILTER_MISS 7 8588#define SQLITE_STMTSTATUS_FILTER_HIT 8 8589#define SQLITE_STMTSTATUS_MEMUSED 99 8590 8591/* 8592** CAPI3REF: Custom Page Cache Object 8593** 8594** The sqlite3_pcache type is opaque. It is implemented by 8595** the pluggable module. The SQLite core has no knowledge of 8596** its size or internal structure and never deals with the 8597** sqlite3_pcache object except by holding and passing pointers 8598** to the object. 8599** 8600** See [sqlite3_pcache_methods2] for additional information. 8601*/ 8602typedef struct sqlite3_pcache sqlite3_pcache; 8603 8604/* 8605** CAPI3REF: Custom Page Cache Object 8606** 8607** The sqlite3_pcache_page object represents a single page in the 8608** page cache. The page cache will allocate instances of this 8609** object. Various methods of the page cache use pointers to instances 8610** of this object as parameters or as their return value. 8611** 8612** See [sqlite3_pcache_methods2] for additional information. 8613*/ 8614typedef struct sqlite3_pcache_page sqlite3_pcache_page; 8615struct sqlite3_pcache_page { 8616 void *pBuf; /* The content of the page */ 8617 void *pExtra; /* Extra information associated with the page */ 8618}; 8619 8620/* 8621** CAPI3REF: Application Defined Page Cache. 8622** KEYWORDS: {page cache} 8623** 8624** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8625** register an alternative page cache implementation by passing in an 8626** instance of the sqlite3_pcache_methods2 structure.)^ 8627** In many applications, most of the heap memory allocated by 8628** SQLite is used for the page cache. 8629** By implementing a 8630** custom page cache using this API, an application can better control 8631** the amount of memory consumed by SQLite, the way in which 8632** that memory is allocated and released, and the policies used to 8633** determine exactly which parts of a database file are cached and for 8634** how long. 8635** 8636** The alternative page cache mechanism is an 8637** extreme measure that is only needed by the most demanding applications. 8638** The built-in page cache is recommended for most uses. 8639** 8640** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8641** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8642** the application may discard the parameter after the call to 8643** [sqlite3_config()] returns.)^ 8644** 8645** [[the xInit() page cache method]] 8646** ^(The xInit() method is called once for each effective 8647** call to [sqlite3_initialize()])^ 8648** (usually only once during the lifetime of the process). ^(The xInit() 8649** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8650** The intent of the xInit() method is to set up global data structures 8651** required by the custom page cache implementation. 8652** ^(If the xInit() method is NULL, then the 8653** built-in default page cache is used instead of the application defined 8654** page cache.)^ 8655** 8656** [[the xShutdown() page cache method]] 8657** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8658** It can be used to clean up 8659** any outstanding resources before process shutdown, if required. 8660** ^The xShutdown() method may be NULL. 8661** 8662** ^SQLite automatically serializes calls to the xInit method, 8663** so the xInit method need not be threadsafe. ^The 8664** xShutdown method is only called from [sqlite3_shutdown()] so it does 8665** not need to be threadsafe either. All other methods must be threadsafe 8666** in multithreaded applications. 8667** 8668** ^SQLite will never invoke xInit() more than once without an intervening 8669** call to xShutdown(). 8670** 8671** [[the xCreate() page cache methods]] 8672** ^SQLite invokes the xCreate() method to construct a new cache instance. 8673** SQLite will typically create one cache instance for each open database file, 8674** though this is not guaranteed. ^The 8675** first parameter, szPage, is the size in bytes of the pages that must 8676** be allocated by the cache. ^szPage will always a power of two. ^The 8677** second parameter szExtra is a number of bytes of extra storage 8678** associated with each page cache entry. ^The szExtra parameter will 8679** a number less than 250. SQLite will use the 8680** extra szExtra bytes on each page to store metadata about the underlying 8681** database page on disk. The value passed into szExtra depends 8682** on the SQLite version, the target platform, and how SQLite was compiled. 8683** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8684** created will be used to cache database pages of a file stored on disk, or 8685** false if it is used for an in-memory database. The cache implementation 8686** does not have to do anything special based with the value of bPurgeable; 8687** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 8688** never invoke xUnpin() except to deliberately delete a page. 8689** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 8690** false will always have the "discard" flag set to true. 8691** ^Hence, a cache created with bPurgeable false will 8692** never contain any unpinned pages. 8693** 8694** [[the xCachesize() page cache method]] 8695** ^(The xCachesize() method may be called at any time by SQLite to set the 8696** suggested maximum cache-size (number of pages stored by) the cache 8697** instance passed as the first argument. This is the value configured using 8698** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 8699** parameter, the implementation is not required to do anything with this 8700** value; it is advisory only. 8701** 8702** [[the xPagecount() page cache methods]] 8703** The xPagecount() method must return the number of pages currently 8704** stored in the cache, both pinned and unpinned. 8705** 8706** [[the xFetch() page cache methods]] 8707** The xFetch() method locates a page in the cache and returns a pointer to 8708** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 8709** The pBuf element of the returned sqlite3_pcache_page object will be a 8710** pointer to a buffer of szPage bytes used to store the content of a 8711** single database page. The pExtra element of sqlite3_pcache_page will be 8712** a pointer to the szExtra bytes of extra storage that SQLite has requested 8713** for each entry in the page cache. 8714** 8715** The page to be fetched is determined by the key. ^The minimum key value 8716** is 1. After it has been retrieved using xFetch, the page is considered 8717** to be "pinned". 8718** 8719** If the requested page is already in the page cache, then the page cache 8720** implementation must return a pointer to the page buffer with its content 8721** intact. If the requested page is not already in the cache, then the 8722** cache implementation should use the value of the createFlag 8723** parameter to help it determined what action to take: 8724** 8725** <table border=1 width=85% align=center> 8726** <tr><th> createFlag <th> Behavior when page is not already in cache 8727** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 8728** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 8729** Otherwise return NULL. 8730** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 8731** NULL if allocating a new page is effectively impossible. 8732** </table> 8733** 8734** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 8735** will only use a createFlag of 2 after a prior call with a createFlag of 1 8736** failed.)^ In between the xFetch() calls, SQLite may 8737** attempt to unpin one or more cache pages by spilling the content of 8738** pinned pages to disk and synching the operating system disk cache. 8739** 8740** [[the xUnpin() page cache method]] 8741** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 8742** as its second argument. If the third parameter, discard, is non-zero, 8743** then the page must be evicted from the cache. 8744** ^If the discard parameter is 8745** zero, then the page may be discarded or retained at the discretion of 8746** page cache implementation. ^The page cache implementation 8747** may choose to evict unpinned pages at any time. 8748** 8749** The cache must not perform any reference counting. A single 8750** call to xUnpin() unpins the page regardless of the number of prior calls 8751** to xFetch(). 8752** 8753** [[the xRekey() page cache methods]] 8754** The xRekey() method is used to change the key value associated with the 8755** page passed as the second argument. If the cache 8756** previously contains an entry associated with newKey, it must be 8757** discarded. ^Any prior cache entry associated with newKey is guaranteed not 8758** to be pinned. 8759** 8760** When SQLite calls the xTruncate() method, the cache must discard all 8761** existing cache entries with page numbers (keys) greater than or equal 8762** to the value of the iLimit parameter passed to xTruncate(). If any 8763** of these pages are pinned, they are implicitly unpinned, meaning that 8764** they can be safely discarded. 8765** 8766** [[the xDestroy() page cache method]] 8767** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 8768** All resources associated with the specified cache should be freed. ^After 8769** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 8770** handle invalid, and will not use it with any other sqlite3_pcache_methods2 8771** functions. 8772** 8773** [[the xShrink() page cache method]] 8774** ^SQLite invokes the xShrink() method when it wants the page cache to 8775** free up as much of heap memory as possible. The page cache implementation 8776** is not obligated to free any memory, but well-behaved implementations should 8777** do their best. 8778*/ 8779typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 8780struct sqlite3_pcache_methods2 { 8781 int iVersion; 8782 void *pArg; 8783 int (*xInit)(void*); 8784 void (*xShutdown)(void*); 8785 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 8786 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8787 int (*xPagecount)(sqlite3_pcache*); 8788 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8789 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 8790 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 8791 unsigned oldKey, unsigned newKey); 8792 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8793 void (*xDestroy)(sqlite3_pcache*); 8794 void (*xShrink)(sqlite3_pcache*); 8795}; 8796 8797/* 8798** This is the obsolete pcache_methods object that has now been replaced 8799** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 8800** retained in the header file for backwards compatibility only. 8801*/ 8802typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 8803struct sqlite3_pcache_methods { 8804 void *pArg; 8805 int (*xInit)(void*); 8806 void (*xShutdown)(void*); 8807 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 8808 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 8809 int (*xPagecount)(sqlite3_pcache*); 8810 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 8811 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 8812 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 8813 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 8814 void (*xDestroy)(sqlite3_pcache*); 8815}; 8816 8817 8818/* 8819** CAPI3REF: Online Backup Object 8820** 8821** The sqlite3_backup object records state information about an ongoing 8822** online backup operation. ^The sqlite3_backup object is created by 8823** a call to [sqlite3_backup_init()] and is destroyed by a call to 8824** [sqlite3_backup_finish()]. 8825** 8826** See Also: [Using the SQLite Online Backup API] 8827*/ 8828typedef struct sqlite3_backup sqlite3_backup; 8829 8830/* 8831** CAPI3REF: Online Backup API. 8832** 8833** The backup API copies the content of one database into another. 8834** It is useful either for creating backups of databases or 8835** for copying in-memory databases to or from persistent files. 8836** 8837** See Also: [Using the SQLite Online Backup API] 8838** 8839** ^SQLite holds a write transaction open on the destination database file 8840** for the duration of the backup operation. 8841** ^The source database is read-locked only while it is being read; 8842** it is not locked continuously for the entire backup operation. 8843** ^Thus, the backup may be performed on a live source database without 8844** preventing other database connections from 8845** reading or writing to the source database while the backup is underway. 8846** 8847** ^(To perform a backup operation: 8848** <ol> 8849** <li><b>sqlite3_backup_init()</b> is called once to initialize the 8850** backup, 8851** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 8852** the data between the two databases, and finally 8853** <li><b>sqlite3_backup_finish()</b> is called to release all resources 8854** associated with the backup operation. 8855** </ol>)^ 8856** There should be exactly one call to sqlite3_backup_finish() for each 8857** successful call to sqlite3_backup_init(). 8858** 8859** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 8860** 8861** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 8862** [database connection] associated with the destination database 8863** and the database name, respectively. 8864** ^The database name is "main" for the main database, "temp" for the 8865** temporary database, or the name specified after the AS keyword in 8866** an [ATTACH] statement for an attached database. 8867** ^The S and M arguments passed to 8868** sqlite3_backup_init(D,N,S,M) identify the [database connection] 8869** and database name of the source database, respectively. 8870** ^The source and destination [database connections] (parameters S and D) 8871** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 8872** an error. 8873** 8874** ^A call to sqlite3_backup_init() will fail, returning NULL, if 8875** there is already a read or read-write transaction open on the 8876** destination database. 8877** 8878** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 8879** returned and an error code and error message are stored in the 8880** destination [database connection] D. 8881** ^The error code and message for the failed call to sqlite3_backup_init() 8882** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 8883** [sqlite3_errmsg16()] functions. 8884** ^A successful call to sqlite3_backup_init() returns a pointer to an 8885** [sqlite3_backup] object. 8886** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 8887** sqlite3_backup_finish() functions to perform the specified backup 8888** operation. 8889** 8890** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 8891** 8892** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 8893** the source and destination databases specified by [sqlite3_backup] object B. 8894** ^If N is negative, all remaining source pages are copied. 8895** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 8896** are still more pages to be copied, then the function returns [SQLITE_OK]. 8897** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 8898** from source to destination, then it returns [SQLITE_DONE]. 8899** ^If an error occurs while running sqlite3_backup_step(B,N), 8900** then an [error code] is returned. ^As well as [SQLITE_OK] and 8901** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 8902** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 8903** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 8904** 8905** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 8906** <ol> 8907** <li> the destination database was opened read-only, or 8908** <li> the destination database is using write-ahead-log journaling 8909** and the destination and source page sizes differ, or 8910** <li> the destination database is an in-memory database and the 8911** destination and source page sizes differ. 8912** </ol>)^ 8913** 8914** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 8915** the [sqlite3_busy_handler | busy-handler function] 8916** is invoked (if one is specified). ^If the 8917** busy-handler returns non-zero before the lock is available, then 8918** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 8919** sqlite3_backup_step() can be retried later. ^If the source 8920** [database connection] 8921** is being used to write to the source database when sqlite3_backup_step() 8922** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 8923** case the call to sqlite3_backup_step() can be retried later on. ^(If 8924** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 8925** [SQLITE_READONLY] is returned, then 8926** there is no point in retrying the call to sqlite3_backup_step(). These 8927** errors are considered fatal.)^ The application must accept 8928** that the backup operation has failed and pass the backup operation handle 8929** to the sqlite3_backup_finish() to release associated resources. 8930** 8931** ^The first call to sqlite3_backup_step() obtains an exclusive lock 8932** on the destination file. ^The exclusive lock is not released until either 8933** sqlite3_backup_finish() is called or the backup operation is complete 8934** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 8935** sqlite3_backup_step() obtains a [shared lock] on the source database that 8936** lasts for the duration of the sqlite3_backup_step() call. 8937** ^Because the source database is not locked between calls to 8938** sqlite3_backup_step(), the source database may be modified mid-way 8939** through the backup process. ^If the source database is modified by an 8940** external process or via a database connection other than the one being 8941** used by the backup operation, then the backup will be automatically 8942** restarted by the next call to sqlite3_backup_step(). ^If the source 8943** database is modified by the using the same database connection as is used 8944** by the backup operation, then the backup database is automatically 8945** updated at the same time. 8946** 8947** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 8948** 8949** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 8950** application wishes to abandon the backup operation, the application 8951** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 8952** ^The sqlite3_backup_finish() interfaces releases all 8953** resources associated with the [sqlite3_backup] object. 8954** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 8955** active write-transaction on the destination database is rolled back. 8956** The [sqlite3_backup] object is invalid 8957** and may not be used following a call to sqlite3_backup_finish(). 8958** 8959** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 8960** sqlite3_backup_step() errors occurred, regardless or whether or not 8961** sqlite3_backup_step() completed. 8962** ^If an out-of-memory condition or IO error occurred during any prior 8963** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 8964** sqlite3_backup_finish() returns the corresponding [error code]. 8965** 8966** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 8967** is not a permanent error and does not affect the return value of 8968** sqlite3_backup_finish(). 8969** 8970** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 8971** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 8972** 8973** ^The sqlite3_backup_remaining() routine returns the number of pages still 8974** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 8975** ^The sqlite3_backup_pagecount() routine returns the total number of pages 8976** in the source database at the conclusion of the most recent 8977** sqlite3_backup_step(). 8978** ^(The values returned by these functions are only updated by 8979** sqlite3_backup_step(). If the source database is modified in a way that 8980** changes the size of the source database or the number of pages remaining, 8981** those changes are not reflected in the output of sqlite3_backup_pagecount() 8982** and sqlite3_backup_remaining() until after the next 8983** sqlite3_backup_step().)^ 8984** 8985** <b>Concurrent Usage of Database Handles</b> 8986** 8987** ^The source [database connection] may be used by the application for other 8988** purposes while a backup operation is underway or being initialized. 8989** ^If SQLite is compiled and configured to support threadsafe database 8990** connections, then the source database connection may be used concurrently 8991** from within other threads. 8992** 8993** However, the application must guarantee that the destination 8994** [database connection] is not passed to any other API (by any thread) after 8995** sqlite3_backup_init() is called and before the corresponding call to 8996** sqlite3_backup_finish(). SQLite does not currently check to see 8997** if the application incorrectly accesses the destination [database connection] 8998** and so no error code is reported, but the operations may malfunction 8999** nevertheless. Use of the destination database connection while a 9000** backup is in progress might also cause a mutex deadlock. 9001** 9002** If running in [shared cache mode], the application must 9003** guarantee that the shared cache used by the destination database 9004** is not accessed while the backup is running. In practice this means 9005** that the application must guarantee that the disk file being 9006** backed up to is not accessed by any connection within the process, 9007** not just the specific connection that was passed to sqlite3_backup_init(). 9008** 9009** The [sqlite3_backup] object itself is partially threadsafe. Multiple 9010** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 9011** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 9012** APIs are not strictly speaking threadsafe. If they are invoked at the 9013** same time as another thread is invoking sqlite3_backup_step() it is 9014** possible that they return invalid values. 9015*/ 9016sqlite3_backup *sqlite3_backup_init( 9017 sqlite3 *pDest, /* Destination database handle */ 9018 const char *zDestName, /* Destination database name */ 9019 sqlite3 *pSource, /* Source database handle */ 9020 const char *zSourceName /* Source database name */ 9021); 9022int sqlite3_backup_step(sqlite3_backup *p, int nPage); 9023int sqlite3_backup_finish(sqlite3_backup *p); 9024int sqlite3_backup_remaining(sqlite3_backup *p); 9025int sqlite3_backup_pagecount(sqlite3_backup *p); 9026 9027/* 9028** CAPI3REF: Unlock Notification 9029** METHOD: sqlite3 9030** 9031** ^When running in shared-cache mode, a database operation may fail with 9032** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 9033** individual tables within the shared-cache cannot be obtained. See 9034** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 9035** ^This API may be used to register a callback that SQLite will invoke 9036** when the connection currently holding the required lock relinquishes it. 9037** ^This API is only available if the library was compiled with the 9038** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 9039** 9040** See Also: [Using the SQLite Unlock Notification Feature]. 9041** 9042** ^Shared-cache locks are released when a database connection concludes 9043** its current transaction, either by committing it or rolling it back. 9044** 9045** ^When a connection (known as the blocked connection) fails to obtain a 9046** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 9047** identity of the database connection (the blocking connection) that 9048** has locked the required resource is stored internally. ^After an 9049** application receives an SQLITE_LOCKED error, it may call the 9050** sqlite3_unlock_notify() method with the blocked connection handle as 9051** the first argument to register for a callback that will be invoked 9052** when the blocking connections current transaction is concluded. ^The 9053** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 9054** call that concludes the blocking connection's transaction. 9055** 9056** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 9057** there is a chance that the blocking connection will have already 9058** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 9059** If this happens, then the specified callback is invoked immediately, 9060** from within the call to sqlite3_unlock_notify().)^ 9061** 9062** ^If the blocked connection is attempting to obtain a write-lock on a 9063** shared-cache table, and more than one other connection currently holds 9064** a read-lock on the same table, then SQLite arbitrarily selects one of 9065** the other connections to use as the blocking connection. 9066** 9067** ^(There may be at most one unlock-notify callback registered by a 9068** blocked connection. If sqlite3_unlock_notify() is called when the 9069** blocked connection already has a registered unlock-notify callback, 9070** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 9071** called with a NULL pointer as its second argument, then any existing 9072** unlock-notify callback is canceled. ^The blocked connections 9073** unlock-notify callback may also be canceled by closing the blocked 9074** connection using [sqlite3_close()]. 9075** 9076** The unlock-notify callback is not reentrant. If an application invokes 9077** any sqlite3_xxx API functions from within an unlock-notify callback, a 9078** crash or deadlock may be the result. 9079** 9080** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 9081** returns SQLITE_OK. 9082** 9083** <b>Callback Invocation Details</b> 9084** 9085** When an unlock-notify callback is registered, the application provides a 9086** single void* pointer that is passed to the callback when it is invoked. 9087** However, the signature of the callback function allows SQLite to pass 9088** it an array of void* context pointers. The first argument passed to 9089** an unlock-notify callback is a pointer to an array of void* pointers, 9090** and the second is the number of entries in the array. 9091** 9092** When a blocking connection's transaction is concluded, there may be 9093** more than one blocked connection that has registered for an unlock-notify 9094** callback. ^If two or more such blocked connections have specified the 9095** same callback function, then instead of invoking the callback function 9096** multiple times, it is invoked once with the set of void* context pointers 9097** specified by the blocked connections bundled together into an array. 9098** This gives the application an opportunity to prioritize any actions 9099** related to the set of unblocked database connections. 9100** 9101** <b>Deadlock Detection</b> 9102** 9103** Assuming that after registering for an unlock-notify callback a 9104** database waits for the callback to be issued before taking any further 9105** action (a reasonable assumption), then using this API may cause the 9106** application to deadlock. For example, if connection X is waiting for 9107** connection Y's transaction to be concluded, and similarly connection 9108** Y is waiting on connection X's transaction, then neither connection 9109** will proceed and the system may remain deadlocked indefinitely. 9110** 9111** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 9112** detection. ^If a given call to sqlite3_unlock_notify() would put the 9113** system in a deadlocked state, then SQLITE_LOCKED is returned and no 9114** unlock-notify callback is registered. The system is said to be in 9115** a deadlocked state if connection A has registered for an unlock-notify 9116** callback on the conclusion of connection B's transaction, and connection 9117** B has itself registered for an unlock-notify callback when connection 9118** A's transaction is concluded. ^Indirect deadlock is also detected, so 9119** the system is also considered to be deadlocked if connection B has 9120** registered for an unlock-notify callback on the conclusion of connection 9121** C's transaction, where connection C is waiting on connection A. ^Any 9122** number of levels of indirection are allowed. 9123** 9124** <b>The "DROP TABLE" Exception</b> 9125** 9126** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 9127** always appropriate to call sqlite3_unlock_notify(). There is however, 9128** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 9129** SQLite checks if there are any currently executing SELECT statements 9130** that belong to the same connection. If there are, SQLITE_LOCKED is 9131** returned. In this case there is no "blocking connection", so invoking 9132** sqlite3_unlock_notify() results in the unlock-notify callback being 9133** invoked immediately. If the application then re-attempts the "DROP TABLE" 9134** or "DROP INDEX" query, an infinite loop might be the result. 9135** 9136** One way around this problem is to check the extended error code returned 9137** by an sqlite3_step() call. ^(If there is a blocking connection, then the 9138** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 9139** the special "DROP TABLE/INDEX" case, the extended error code is just 9140** SQLITE_LOCKED.)^ 9141*/ 9142int sqlite3_unlock_notify( 9143 sqlite3 *pBlocked, /* Waiting connection */ 9144 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 9145 void *pNotifyArg /* Argument to pass to xNotify */ 9146); 9147 9148 9149/* 9150** CAPI3REF: String Comparison 9151** 9152** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 9153** and extensions to compare the contents of two buffers containing UTF-8 9154** strings in a case-independent fashion, using the same definition of "case 9155** independence" that SQLite uses internally when comparing identifiers. 9156*/ 9157int sqlite3_stricmp(const char *, const char *); 9158int sqlite3_strnicmp(const char *, const char *, int); 9159 9160/* 9161** CAPI3REF: String Globbing 9162* 9163** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 9164** string X matches the [GLOB] pattern P. 9165** ^The definition of [GLOB] pattern matching used in 9166** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 9167** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 9168** is case sensitive. 9169** 9170** Note that this routine returns zero on a match and non-zero if the strings 9171** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9172** 9173** See also: [sqlite3_strlike()]. 9174*/ 9175int sqlite3_strglob(const char *zGlob, const char *zStr); 9176 9177/* 9178** CAPI3REF: String LIKE Matching 9179* 9180** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 9181** string X matches the [LIKE] pattern P with escape character E. 9182** ^The definition of [LIKE] pattern matching used in 9183** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 9184** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 9185** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 9186** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 9187** insensitive - equivalent upper and lower case ASCII characters match 9188** one another. 9189** 9190** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 9191** only ASCII characters are case folded. 9192** 9193** Note that this routine returns zero on a match and non-zero if the strings 9194** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9195** 9196** See also: [sqlite3_strglob()]. 9197*/ 9198int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 9199 9200/* 9201** CAPI3REF: Error Logging Interface 9202** 9203** ^The [sqlite3_log()] interface writes a message into the [error log] 9204** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 9205** ^If logging is enabled, the zFormat string and subsequent arguments are 9206** used with [sqlite3_snprintf()] to generate the final output string. 9207** 9208** The sqlite3_log() interface is intended for use by extensions such as 9209** virtual tables, collating functions, and SQL functions. While there is 9210** nothing to prevent an application from calling sqlite3_log(), doing so 9211** is considered bad form. 9212** 9213** The zFormat string must not be NULL. 9214** 9215** To avoid deadlocks and other threading problems, the sqlite3_log() routine 9216** will not use dynamically allocated memory. The log message is stored in 9217** a fixed-length buffer on the stack. If the log message is longer than 9218** a few hundred characters, it will be truncated to the length of the 9219** buffer. 9220*/ 9221void sqlite3_log(int iErrCode, const char *zFormat, ...); 9222 9223/* 9224** CAPI3REF: Write-Ahead Log Commit Hook 9225** METHOD: sqlite3 9226** 9227** ^The [sqlite3_wal_hook()] function is used to register a callback that 9228** is invoked each time data is committed to a database in wal mode. 9229** 9230** ^(The callback is invoked by SQLite after the commit has taken place and 9231** the associated write-lock on the database released)^, so the implementation 9232** may read, write or [checkpoint] the database as required. 9233** 9234** ^The first parameter passed to the callback function when it is invoked 9235** is a copy of the third parameter passed to sqlite3_wal_hook() when 9236** registering the callback. ^The second is a copy of the database handle. 9237** ^The third parameter is the name of the database that was written to - 9238** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 9239** is the number of pages currently in the write-ahead log file, 9240** including those that were just committed. 9241** 9242** The callback function should normally return [SQLITE_OK]. ^If an error 9243** code is returned, that error will propagate back up through the 9244** SQLite code base to cause the statement that provoked the callback 9245** to report an error, though the commit will have still occurred. If the 9246** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 9247** that does not correspond to any valid SQLite error code, the results 9248** are undefined. 9249** 9250** A single database handle may have at most a single write-ahead log callback 9251** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 9252** previously registered write-ahead log callback. ^The return value is 9253** a copy of the third parameter from the previous call, if any, or 0. 9254** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the 9255** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 9256** overwrite any prior [sqlite3_wal_hook()] settings. 9257*/ 9258void *sqlite3_wal_hook( 9259 sqlite3*, 9260 int(*)(void *,sqlite3*,const char*,int), 9261 void* 9262); 9263 9264/* 9265** CAPI3REF: Configure an auto-checkpoint 9266** METHOD: sqlite3 9267** 9268** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 9269** [sqlite3_wal_hook()] that causes any database on [database connection] D 9270** to automatically [checkpoint] 9271** after committing a transaction if there are N or 9272** more frames in the [write-ahead log] file. ^Passing zero or 9273** a negative value as the nFrame parameter disables automatic 9274** checkpoints entirely. 9275** 9276** ^The callback registered by this function replaces any existing callback 9277** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 9278** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 9279** configured by this function. 9280** 9281** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 9282** from SQL. 9283** 9284** ^Checkpoints initiated by this mechanism are 9285** [sqlite3_wal_checkpoint_v2|PASSIVE]. 9286** 9287** ^Every new [database connection] defaults to having the auto-checkpoint 9288** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 9289** pages. The use of this interface 9290** is only necessary if the default setting is found to be suboptimal 9291** for a particular application. 9292*/ 9293int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 9294 9295/* 9296** CAPI3REF: Checkpoint a database 9297** METHOD: sqlite3 9298** 9299** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 9300** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 9301** 9302** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 9303** [write-ahead log] for database X on [database connection] D to be 9304** transferred into the database file and for the write-ahead log to 9305** be reset. See the [checkpointing] documentation for addition 9306** information. 9307** 9308** This interface used to be the only way to cause a checkpoint to 9309** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 9310** interface was added. This interface is retained for backwards 9311** compatibility and as a convenience for applications that need to manually 9312** start a callback but which do not need the full power (and corresponding 9313** complication) of [sqlite3_wal_checkpoint_v2()]. 9314*/ 9315int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 9316 9317/* 9318** CAPI3REF: Checkpoint a database 9319** METHOD: sqlite3 9320** 9321** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 9322** operation on database X of [database connection] D in mode M. Status 9323** information is written back into integers pointed to by L and C.)^ 9324** ^(The M parameter must be a valid [checkpoint mode]:)^ 9325** 9326** <dl> 9327** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 9328** ^Checkpoint as many frames as possible without waiting for any database 9329** readers or writers to finish, then sync the database file if all frames 9330** in the log were checkpointed. ^The [busy-handler callback] 9331** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 9332** ^On the other hand, passive mode might leave the checkpoint unfinished 9333** if there are concurrent readers or writers. 9334** 9335** <dt>SQLITE_CHECKPOINT_FULL<dd> 9336** ^This mode blocks (it invokes the 9337** [sqlite3_busy_handler|busy-handler callback]) until there is no 9338** database writer and all readers are reading from the most recent database 9339** snapshot. ^It then checkpoints all frames in the log file and syncs the 9340** database file. ^This mode blocks new database writers while it is pending, 9341** but new database readers are allowed to continue unimpeded. 9342** 9343** <dt>SQLITE_CHECKPOINT_RESTART<dd> 9344** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 9345** that after checkpointing the log file it blocks (calls the 9346** [busy-handler callback]) 9347** until all readers are reading from the database file only. ^This ensures 9348** that the next writer will restart the log file from the beginning. 9349** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 9350** database writer attempts while it is pending, but does not impede readers. 9351** 9352** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 9353** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 9354** addition that it also truncates the log file to zero bytes just prior 9355** to a successful return. 9356** </dl> 9357** 9358** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 9359** the log file or to -1 if the checkpoint could not run because 9360** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 9361** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 9362** log file (including any that were already checkpointed before the function 9363** was called) or to -1 if the checkpoint could not run due to an error or 9364** because the database is not in WAL mode. ^Note that upon successful 9365** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 9366** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 9367** 9368** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 9369** any other process is running a checkpoint operation at the same time, the 9370** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 9371** busy-handler configured, it will not be invoked in this case. 9372** 9373** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 9374** exclusive "writer" lock on the database file. ^If the writer lock cannot be 9375** obtained immediately, and a busy-handler is configured, it is invoked and 9376** the writer lock retried until either the busy-handler returns 0 or the lock 9377** is successfully obtained. ^The busy-handler is also invoked while waiting for 9378** database readers as described above. ^If the busy-handler returns 0 before 9379** the writer lock is obtained or while waiting for database readers, the 9380** checkpoint operation proceeds from that point in the same way as 9381** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 9382** without blocking any further. ^SQLITE_BUSY is returned in this case. 9383** 9384** ^If parameter zDb is NULL or points to a zero length string, then the 9385** specified operation is attempted on all WAL databases [attached] to 9386** [database connection] db. In this case the 9387** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 9388** an SQLITE_BUSY error is encountered when processing one or more of the 9389** attached WAL databases, the operation is still attempted on any remaining 9390** attached databases and SQLITE_BUSY is returned at the end. ^If any other 9391** error occurs while processing an attached database, processing is abandoned 9392** and the error code is returned to the caller immediately. ^If no error 9393** (SQLITE_BUSY or otherwise) is encountered while processing the attached 9394** databases, SQLITE_OK is returned. 9395** 9396** ^If database zDb is the name of an attached database that is not in WAL 9397** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 9398** zDb is not NULL (or a zero length string) and is not the name of any 9399** attached database, SQLITE_ERROR is returned to the caller. 9400** 9401** ^Unless it returns SQLITE_MISUSE, 9402** the sqlite3_wal_checkpoint_v2() interface 9403** sets the error information that is queried by 9404** [sqlite3_errcode()] and [sqlite3_errmsg()]. 9405** 9406** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 9407** from SQL. 9408*/ 9409int sqlite3_wal_checkpoint_v2( 9410 sqlite3 *db, /* Database handle */ 9411 const char *zDb, /* Name of attached database (or NULL) */ 9412 int eMode, /* SQLITE_CHECKPOINT_* value */ 9413 int *pnLog, /* OUT: Size of WAL log in frames */ 9414 int *pnCkpt /* OUT: Total number of frames checkpointed */ 9415); 9416 9417/* 9418** CAPI3REF: Checkpoint Mode Values 9419** KEYWORDS: {checkpoint mode} 9420** 9421** These constants define all valid values for the "checkpoint mode" passed 9422** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 9423** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 9424** meaning of each of these checkpoint modes. 9425*/ 9426#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9427#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9428#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ 9429#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9430 9431/* 9432** CAPI3REF: Virtual Table Interface Configuration 9433** 9434** This function may be called by either the [xConnect] or [xCreate] method 9435** of a [virtual table] implementation to configure 9436** various facets of the virtual table interface. 9437** 9438** If this interface is invoked outside the context of an xConnect or 9439** xCreate virtual table method then the behavior is undefined. 9440** 9441** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9442** [database connection] in which the virtual table is being created and 9443** which is passed in as the first argument to the [xConnect] or [xCreate] 9444** method that is invoking sqlite3_vtab_config(). The C parameter is one 9445** of the [virtual table configuration options]. The presence and meaning 9446** of parameters after C depend on which [virtual table configuration option] 9447** is used. 9448*/ 9449int sqlite3_vtab_config(sqlite3*, int op, ...); 9450 9451/* 9452** CAPI3REF: Virtual Table Configuration Options 9453** KEYWORDS: {virtual table configuration options} 9454** KEYWORDS: {virtual table configuration option} 9455** 9456** These macros define the various options to the 9457** [sqlite3_vtab_config()] interface that [virtual table] implementations 9458** can use to customize and optimize their behavior. 9459** 9460** <dl> 9461** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9462** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9463** <dd>Calls of the form 9464** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9465** where X is an integer. If X is zero, then the [virtual table] whose 9466** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9467** support constraints. In this configuration (which is the default) if 9468** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9469** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9470** specified as part of the users SQL statement, regardless of the actual 9471** ON CONFLICT mode specified. 9472** 9473** If X is non-zero, then the virtual table implementation guarantees 9474** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9475** any modifications to internal or persistent data structures have been made. 9476** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9477** is able to roll back a statement or database transaction, and abandon 9478** or continue processing the current SQL statement as appropriate. 9479** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9480** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9481** had been ABORT. 9482** 9483** Virtual table implementations that are required to handle OR REPLACE 9484** must do so within the [xUpdate] method. If a call to the 9485** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9486** CONFLICT policy is REPLACE, the virtual table implementation should 9487** silently replace the appropriate rows within the xUpdate callback and 9488** return SQLITE_OK. Or, if this is not possible, it may return 9489** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9490** constraint handling. 9491** </dd> 9492** 9493** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9494** <dd>Calls of the form 9495** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9496** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9497** prohibits that virtual table from being used from within triggers and 9498** views. 9499** </dd> 9500** 9501** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9502** <dd>Calls of the form 9503** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9504** the [xConnect] or [xCreate] methods of a [virtual table] implmentation 9505** identify that virtual table as being safe to use from within triggers 9506** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9507** virtual table can do no serious harm even if it is controlled by a 9508** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9509** flag unless absolutely necessary. 9510** </dd> 9511** </dl> 9512*/ 9513#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9514#define SQLITE_VTAB_INNOCUOUS 2 9515#define SQLITE_VTAB_DIRECTONLY 3 9516 9517/* 9518** CAPI3REF: Determine The Virtual Table Conflict Policy 9519** 9520** This function may only be called from within a call to the [xUpdate] method 9521** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9522** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9523** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9524** of the SQL statement that triggered the call to the [xUpdate] method of the 9525** [virtual table]. 9526*/ 9527int sqlite3_vtab_on_conflict(sqlite3 *); 9528 9529/* 9530** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9531** 9532** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9533** method of a [virtual table], then it might return true if the 9534** column is being fetched as part of an UPDATE operation during which the 9535** column value will not change. The virtual table implementation can use 9536** this hint as permission to substitute a return value that is less 9537** expensive to compute and that the corresponding 9538** [xUpdate] method understands as a "no-change" value. 9539** 9540** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9541** the column is not changed by the UPDATE statement, then the xColumn 9542** method can optionally return without setting a result, without calling 9543** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9544** In that case, [sqlite3_value_nochange(X)] will return true for the 9545** same column in the [xUpdate] method. 9546** 9547** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 9548** implementations should continue to give a correct answer even if the 9549** sqlite3_vtab_nochange() interface were to always return false. In the 9550** current implementation, the sqlite3_vtab_nochange() interface does always 9551** returns false for the enhanced [UPDATE FROM] statement. 9552*/ 9553int sqlite3_vtab_nochange(sqlite3_context*); 9554 9555/* 9556** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9557** METHOD: sqlite3_index_info 9558** 9559** This function may only be called from within a call to the [xBestIndex] 9560** method of a [virtual table]. This function returns a pointer to a string 9561** that is the name of the appropriate collation sequence to use for text 9562** comparisons on the constraint identified by its arguments. 9563** 9564** The first argument must be the pointer to the [sqlite3_index_info] object 9565** that is the first parameter to the xBestIndex() method. The second argument 9566** must be an index into the aConstraint[] array belonging to the 9567** sqlite3_index_info structure passed to xBestIndex. 9568** 9569** Important: 9570** The first parameter must be the same pointer that is passed into the 9571** xBestMethod() method. The first parameter may not be a pointer to a 9572** different [sqlite3_index_info] object, even an exact copy. 9573** 9574** The return value is computed as follows: 9575** 9576** <ol> 9577** <li><p> If the constraint comes from a WHERE clause expression that contains 9578** a [COLLATE operator], then the name of the collation specified by 9579** that COLLATE operator is returned. 9580** <li><p> If there is no COLLATE operator, but the column that is the subject 9581** of the constraint specifies an alternative collating sequence via 9582** a [COLLATE clause] on the column definition within the CREATE TABLE 9583** statement that was passed into [sqlite3_declare_vtab()], then the 9584** name of that alternative collating sequence is returned. 9585** <li><p> Otherwise, "BINARY" is returned. 9586** </ol> 9587*/ 9588SQLITE_EXPERIMENTAL const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9589 9590/* 9591** CAPI3REF: Determine if a virtual table query is DISTINCT 9592** METHOD: sqlite3_index_info 9593** 9594** This API may only be used from within an [xBestIndex|xBestIndex method] 9595** of a [virtual table] implementation. The result of calling this 9596** interface from outside of xBestIndex() is undefined and probably harmful. 9597** 9598** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and 9599** 3. The integer returned by sqlite3_vtab_distinct() 9600** gives the virtual table additional information about how the query 9601** planner wants the output to be ordered. As long as the virtual table 9602** can meet the ordering requirements of the query planner, it may set 9603** the "orderByConsumed" flag. 9604** 9605** <ol><li value="0"><p> 9606** ^If the sqlite3_vtab_distinct() interface returns 0, that means 9607** that the query planner needs the virtual table to return all rows in the 9608** sort order defined by the "nOrderBy" and "aOrderBy" fields of the 9609** [sqlite3_index_info] object. This is the default expectation. If the 9610** virtual table outputs all rows in sorted order, then it is always safe for 9611** the xBestIndex method to set the "orderByConsumed" flag, regardless of 9612** the return value from sqlite3_vtab_distinct(). 9613** <li value="1"><p> 9614** ^(If the sqlite3_vtab_distinct() interface returns 1, that means 9615** that the query planner does not need the rows to be returned in sorted order 9616** as long as all rows with the same values in all columns identified by the 9617** "aOrderBy" field are adjacent.)^ This mode is used when the query planner 9618** is doing a GROUP BY. 9619** <li value="2"><p> 9620** ^(If the sqlite3_vtab_distinct() interface returns 2, that means 9621** that the query planner does not need the rows returned in any particular 9622** order, as long as rows with the same values in all "aOrderBy" columns 9623** are adjacent.)^ ^(Furthermore, only a single row for each particular 9624** combination of values in the columns identified by the "aOrderBy" field 9625** needs to be returned.)^ ^It is always ok for two or more rows with the same 9626** values in all "aOrderBy" columns to be returned, as long as all such rows 9627** are adjacent. ^The virtual table may, if it chooses, omit extra rows 9628** that have the same value for all columns identified by "aOrderBy". 9629** ^However omitting the extra rows is optional. 9630** This mode is used for a DISTINCT query. 9631** <li value="3"><p> 9632** ^(If the sqlite3_vtab_distinct() interface returns 3, that means 9633** that the query planner needs only distinct rows but it does need the 9634** rows to be sorted.)^ ^The virtual table implementation is free to omit 9635** rows that are identical in all aOrderBy columns, if it wants to, but 9636** it is not required to omit any rows. This mode is used for queries 9637** that have both DISTINCT and ORDER BY clauses. 9638** </ol> 9639** 9640** ^For the purposes of comparing virtual table output values to see if the 9641** values are same value for sorting purposes, two NULL values are considered 9642** to be the same. In other words, the comparison operator is "IS" 9643** (or "IS NOT DISTINCT FROM") and not "==". 9644** 9645** If a virtual table implementation is unable to meet the requirements 9646** specified above, then it must not set the "orderByConsumed" flag in the 9647** [sqlite3_index_info] object or an incorrect answer may result. 9648** 9649** ^A virtual table implementation is always free to return rows in any order 9650** it wants, as long as the "orderByConsumed" flag is not set. ^When the 9651** the "orderByConsumed" flag is unset, the query planner will add extra 9652** [bytecode] to ensure that the final results returned by the SQL query are 9653** ordered correctly. The use of the "orderByConsumed" flag and the 9654** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful 9655** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" 9656** flag might help queries against a virtual table to run faster. Being 9657** overly aggressive and setting the "orderByConsumed" flag when it is not 9658** valid to do so, on the other hand, might cause SQLite to return incorrect 9659** results. 9660*/ 9661int sqlite3_vtab_distinct(sqlite3_index_info*); 9662 9663/* 9664** CAPI3REF: Identify and handle IN constraints in xBestIndex 9665** 9666** This interface may only be used from within an 9667** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. 9668** The result of invoking this interface from any other context is 9669** undefined and probably harmful. 9670** 9671** ^(A constraint on a virtual table of the form 9672** "[IN operator|column IN (...)]" is 9673** communicated to the xBestIndex method as a 9674** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use 9675** this constraint, it must set the corresponding 9676** aConstraintUsage[].argvIndex to a postive integer. ^(Then, under 9677** the usual mode of handling IN operators, SQLite generates [bytecode] 9678** that invokes the [xFilter|xFilter() method] once for each value 9679** on the right-hand side of the IN operator.)^ Thus the virtual table 9680** only sees a single value from the right-hand side of the IN operator 9681** at a time. 9682** 9683** In some cases, however, it would be advantageous for the virtual 9684** table to see all values on the right-hand of the IN operator all at 9685** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: 9686** 9687** <ol> 9688** <li><p> 9689** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) 9690** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint 9691** is an [IN operator] that can be processed all at once. ^In other words, 9692** sqlite3_vtab_in() with -1 in the third argument is a mechanism 9693** by which the virtual table can ask SQLite if all-at-once processing 9694** of the IN operator is even possible. 9695** 9696** <li><p> 9697** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates 9698** to SQLite that the virtual table does or does not want to process 9699** the IN operator all-at-once, respectively. ^Thus when the third 9700** parameter (F) is non-negative, this interface is the mechanism by 9701** which the virtual table tells SQLite how it wants to process the 9702** IN operator. 9703** </ol> 9704** 9705** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times 9706** within the same xBestIndex method call. ^For any given P,N pair, 9707** the return value from sqlite3_vtab_in(P,N,F) will always be the same 9708** within the same xBestIndex call. ^If the interface returns true 9709** (non-zero), that means that the constraint is an IN operator 9710** that can be processed all-at-once. ^If the constraint is not an IN 9711** operator or cannot be processed all-at-once, then the interface returns 9712** false. 9713** 9714** ^(All-at-once processing of the IN operator is selected if both of the 9715** following conditions are met: 9716** 9717** <ol> 9718** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive 9719** integer. This is how the virtual table tells SQLite that it wants to 9720** use the N-th constraint. 9721** 9722** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was 9723** non-negative had F>=1. 9724** </ol>)^ 9725** 9726** ^If either or both of the conditions above are false, then SQLite uses 9727** the traditional one-at-a-time processing strategy for the IN constraint. 9728** ^If both conditions are true, then the argvIndex-th parameter to the 9729** xFilter method will be an [sqlite3_value] that appears to be NULL, 9730** but which can be passed to [sqlite3_vtab_in_first()] and 9731** [sqlite3_vtab_in_next()] to find all values on the right-hand side 9732** of the IN constraint. 9733*/ 9734int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); 9735 9736/* 9737** CAPI3REF: Find all elements on the right-hand side of an IN constraint. 9738** 9739** These interfaces are only useful from within the 9740** [xFilter|xFilter() method] of a [virtual table] implementation. 9741** The result of invoking these interfaces from any other context 9742** is undefined and probably harmful. 9743** 9744** The X parameter in a call to sqlite3_vtab_in_first(X,P) or 9745** sqlite3_vtab_in_next(X,P) must be one of the parameters to the 9746** xFilter method which invokes these routines, and specifically 9747** a parameter that was previously selected for all-at-once IN constraint 9748** processing use the [sqlite3_vtab_in()] interface in the 9749** [xBestIndex|xBestIndex method]. ^(If the X parameter is not 9750** an xFilter argument that was selected for all-at-once IN constraint 9751** processing, then these routines return [SQLITE_MISUSE])^ or perhaps 9752** exhibit some other undefined or harmful behavior. 9753** 9754** ^(Use these routines to access all values on the right-hand side 9755** of the IN constraint using code like the following: 9756** 9757** <blockquote><pre> 9758** for(rc=sqlite3_vtab_in_first(pList, &pVal); 9759** rc==SQLITE_OK && pVal 9760** rc=sqlite3_vtab_in_next(pList, &pVal) 9761** ){ 9762** // do something with pVal 9763** } 9764** if( rc!=SQLITE_OK ){ 9765** // an error has occurred 9766** } 9767** </pre></blockquote>)^ 9768** 9769** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) 9770** routines return SQLITE_OK and set *P to point to the first or next value 9771** on the RHS of the IN constraint. ^If there are no more values on the 9772** right hand side of the IN constraint, then *P is set to NULL and these 9773** routines return [SQLITE_DONE]. ^The return value might be 9774** some other value, such as SQLITE_NOMEM, in the event of a malfunction. 9775** 9776** The *ppOut values returned by these routines are only valid until the 9777** next call to either of these routines or until the end of the xFilter 9778** method from which these routines were called. If the virtual table 9779** implementation needs to retain the *ppOut values for longer, it must make 9780** copies. The *ppOut values are [protected sqlite3_value|protected]. 9781*/ 9782int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); 9783int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); 9784 9785/* 9786** CAPI3REF: Constraint values in xBestIndex() 9787** METHOD: sqlite3_index_info 9788** 9789** This API may only be used from within the [xBestIndex|xBestIndex method] 9790** of a [virtual table] implementation. The result of calling this interface 9791** from outside of an xBestIndex method are undefined and probably harmful. 9792** 9793** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within 9794** the [xBestIndex] method of a [virtual table] implementation, with P being 9795** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and 9796** J being a 0-based index into P->aConstraint[], then this routine 9797** attempts to set *V to the value of the right-hand operand of 9798** that constraint if the right-hand operand is known. ^If the 9799** right-hand operand is not known, then *V is set to a NULL pointer. 9800** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if 9801** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) 9802** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th 9803** constraint is not available. ^The sqlite3_vtab_rhs_value() interface 9804** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if 9805** something goes wrong. 9806** 9807** The sqlite3_vtab_rhs_value() interface is usually only successful if 9808** the right-hand operand of a constraint is a literal value in the original 9809** SQL statement. If the right-hand operand is an expression or a reference 9810** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() 9811** will probably return [SQLITE_NOTFOUND]. 9812** 9813** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and 9814** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such 9815** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ 9816** 9817** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value 9818** and remains valid for the duration of the xBestIndex method call. 9819** ^When xBestIndex returns, the sqlite3_value object returned by 9820** sqlite3_vtab_rhs_value() is automatically deallocated. 9821** 9822** The "_rhs_" in the name of this routine is an abbreviation for 9823** "Right-Hand Side". 9824*/ 9825int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); 9826 9827/* 9828** CAPI3REF: Conflict resolution modes 9829** KEYWORDS: {conflict resolution mode} 9830** 9831** These constants are returned by [sqlite3_vtab_on_conflict()] to 9832** inform a [virtual table] implementation what the [ON CONFLICT] mode 9833** is for the SQL statement being evaluated. 9834** 9835** Note that the [SQLITE_IGNORE] constant is also used as a potential 9836** return value from the [sqlite3_set_authorizer()] callback and that 9837** [SQLITE_ABORT] is also a [result code]. 9838*/ 9839#define SQLITE_ROLLBACK 1 9840/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 9841#define SQLITE_FAIL 3 9842/* #define SQLITE_ABORT 4 // Also an error code */ 9843#define SQLITE_REPLACE 5 9844 9845/* 9846** CAPI3REF: Prepared Statement Scan Status Opcodes 9847** KEYWORDS: {scanstatus options} 9848** 9849** The following constants can be used for the T parameter to the 9850** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 9851** different metric for sqlite3_stmt_scanstatus() to return. 9852** 9853** When the value returned to V is a string, space to hold that string is 9854** managed by the prepared statement S and will be automatically freed when 9855** S is finalized. 9856** 9857** <dl> 9858** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 9859** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 9860** set to the total number of times that the X-th loop has run.</dd> 9861** 9862** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 9863** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 9864** to the total number of rows examined by all iterations of the X-th loop.</dd> 9865** 9866** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 9867** <dd>^The "double" variable pointed to by the V parameter will be set to the 9868** query planner's estimate for the average number of rows output from each 9869** iteration of the X-th loop. If the query planner's estimates was accurate, 9870** then this value will approximate the quotient NVISIT/NLOOP and the 9871** product of this value for all prior loops with the same SELECTID will 9872** be the NLOOP value for the current loop. 9873** 9874** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 9875** <dd>^The "const char *" variable pointed to by the V parameter will be set 9876** to a zero-terminated UTF-8 string containing the name of the index or table 9877** used for the X-th loop. 9878** 9879** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 9880** <dd>^The "const char *" variable pointed to by the V parameter will be set 9881** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 9882** description for the X-th loop. 9883** 9884** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 9885** <dd>^The "int" variable pointed to by the V parameter will be set to the 9886** "select-id" for the X-th loop. The select-id identifies which query or 9887** subquery the loop is part of. The main query has a select-id of zero. 9888** The select-id is the same value as is output in the first column 9889** of an [EXPLAIN QUERY PLAN] query. 9890** </dl> 9891*/ 9892#define SQLITE_SCANSTAT_NLOOP 0 9893#define SQLITE_SCANSTAT_NVISIT 1 9894#define SQLITE_SCANSTAT_EST 2 9895#define SQLITE_SCANSTAT_NAME 3 9896#define SQLITE_SCANSTAT_EXPLAIN 4 9897#define SQLITE_SCANSTAT_SELECTID 5 9898 9899/* 9900** CAPI3REF: Prepared Statement Scan Status 9901** METHOD: sqlite3_stmt 9902** 9903** This interface returns information about the predicted and measured 9904** performance for pStmt. Advanced applications can use this 9905** interface to compare the predicted and the measured performance and 9906** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 9907** 9908** Since this interface is expected to be rarely used, it is only 9909** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 9910** compile-time option. 9911** 9912** The "iScanStatusOp" parameter determines which status information to return. 9913** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 9914** of this interface is undefined. 9915** ^The requested measurement is written into a variable pointed to by 9916** the "pOut" parameter. 9917** Parameter "idx" identifies the specific loop to retrieve statistics for. 9918** Loops are numbered starting from zero. ^If idx is out of range - less than 9919** zero or greater than or equal to the total number of loops used to implement 9920** the statement - a non-zero value is returned and the variable that pOut 9921** points to is unchanged. 9922** 9923** ^Statistics might not be available for all loops in all statements. ^In cases 9924** where there exist loops with no available statistics, this function behaves 9925** as if the loop did not exist - it returns non-zero and leave the variable 9926** that pOut points to unchanged. 9927** 9928** See also: [sqlite3_stmt_scanstatus_reset()] 9929*/ 9930int sqlite3_stmt_scanstatus( 9931 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 9932 int idx, /* Index of loop to report on */ 9933 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 9934 void *pOut /* Result written here */ 9935); 9936 9937/* 9938** CAPI3REF: Zero Scan-Status Counters 9939** METHOD: sqlite3_stmt 9940** 9941** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 9942** 9943** This API is only available if the library is built with pre-processor 9944** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 9945*/ 9946void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 9947 9948/* 9949** CAPI3REF: Flush caches to disk mid-transaction 9950** METHOD: sqlite3 9951** 9952** ^If a write-transaction is open on [database connection] D when the 9953** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 9954** pages in the pager-cache that are not currently in use are written out 9955** to disk. A dirty page may be in use if a database cursor created by an 9956** active SQL statement is reading from it, or if it is page 1 of a database 9957** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 9958** interface flushes caches for all schemas - "main", "temp", and 9959** any [attached] databases. 9960** 9961** ^If this function needs to obtain extra database locks before dirty pages 9962** can be flushed to disk, it does so. ^If those locks cannot be obtained 9963** immediately and there is a busy-handler callback configured, it is invoked 9964** in the usual manner. ^If the required lock still cannot be obtained, then 9965** the database is skipped and an attempt made to flush any dirty pages 9966** belonging to the next (if any) database. ^If any databases are skipped 9967** because locks cannot be obtained, but no other error occurs, this 9968** function returns SQLITE_BUSY. 9969** 9970** ^If any other error occurs while flushing dirty pages to disk (for 9971** example an IO error or out-of-memory condition), then processing is 9972** abandoned and an SQLite [error code] is returned to the caller immediately. 9973** 9974** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 9975** 9976** ^This function does not set the database handle error code or message 9977** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 9978*/ 9979int sqlite3_db_cacheflush(sqlite3*); 9980 9981/* 9982** CAPI3REF: The pre-update hook. 9983** METHOD: sqlite3 9984** 9985** ^These interfaces are only available if SQLite is compiled using the 9986** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 9987** 9988** ^The [sqlite3_preupdate_hook()] interface registers a callback function 9989** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 9990** on a database table. 9991** ^At most one preupdate hook may be registered at a time on a single 9992** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 9993** the previous setting. 9994** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 9995** with a NULL pointer as the second parameter. 9996** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 9997** the first parameter to callbacks. 9998** 9999** ^The preupdate hook only fires for changes to real database tables; the 10000** preupdate hook is not invoked for changes to [virtual tables] or to 10001** system tables like sqlite_sequence or sqlite_stat1. 10002** 10003** ^The second parameter to the preupdate callback is a pointer to 10004** the [database connection] that registered the preupdate hook. 10005** ^The third parameter to the preupdate callback is one of the constants 10006** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 10007** kind of update operation that is about to occur. 10008** ^(The fourth parameter to the preupdate callback is the name of the 10009** database within the database connection that is being modified. This 10010** will be "main" for the main database or "temp" for TEMP tables or 10011** the name given after the AS keyword in the [ATTACH] statement for attached 10012** databases.)^ 10013** ^The fifth parameter to the preupdate callback is the name of the 10014** table that is being modified. 10015** 10016** For an UPDATE or DELETE operation on a [rowid table], the sixth 10017** parameter passed to the preupdate callback is the initial [rowid] of the 10018** row being modified or deleted. For an INSERT operation on a rowid table, 10019** or any operation on a WITHOUT ROWID table, the value of the sixth 10020** parameter is undefined. For an INSERT or UPDATE on a rowid table the 10021** seventh parameter is the final rowid value of the row being inserted 10022** or updated. The value of the seventh parameter passed to the callback 10023** function is not defined for operations on WITHOUT ROWID tables, or for 10024** DELETE operations on rowid tables. 10025** 10026** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 10027** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 10028** provide additional information about a preupdate event. These routines 10029** may only be called from within a preupdate callback. Invoking any of 10030** these routines from outside of a preupdate callback or with a 10031** [database connection] pointer that is different from the one supplied 10032** to the preupdate callback results in undefined and probably undesirable 10033** behavior. 10034** 10035** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 10036** in the row that is being inserted, updated, or deleted. 10037** 10038** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 10039** a [protected sqlite3_value] that contains the value of the Nth column of 10040** the table row before it is updated. The N parameter must be between 0 10041** and one less than the number of columns or the behavior will be 10042** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 10043** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 10044** behavior is undefined. The [sqlite3_value] that P points to 10045** will be destroyed when the preupdate callback returns. 10046** 10047** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 10048** a [protected sqlite3_value] that contains the value of the Nth column of 10049** the table row after it is updated. The N parameter must be between 0 10050** and one less than the number of columns or the behavior will be 10051** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 10052** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 10053** behavior is undefined. The [sqlite3_value] that P points to 10054** will be destroyed when the preupdate callback returns. 10055** 10056** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 10057** callback was invoked as a result of a direct insert, update, or delete 10058** operation; or 1 for inserts, updates, or deletes invoked by top-level 10059** triggers; or 2 for changes resulting from triggers called by top-level 10060** triggers; and so forth. 10061** 10062** When the [sqlite3_blob_write()] API is used to update a blob column, 10063** the pre-update hook is invoked with SQLITE_DELETE. This is because the 10064** in this case the new values are not available. In this case, when a 10065** callback made with op==SQLITE_DELETE is actuall a write using the 10066** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns 10067** the index of the column being written. In other cases, where the 10068** pre-update hook is being invoked for some other reason, including a 10069** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. 10070** 10071** See also: [sqlite3_update_hook()] 10072*/ 10073#if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 10074void *sqlite3_preupdate_hook( 10075 sqlite3 *db, 10076 void(*xPreUpdate)( 10077 void *pCtx, /* Copy of third arg to preupdate_hook() */ 10078 sqlite3 *db, /* Database handle */ 10079 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 10080 char const *zDb, /* Database name */ 10081 char const *zName, /* Table name */ 10082 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 10083 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 10084 ), 10085 void* 10086); 10087int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 10088int sqlite3_preupdate_count(sqlite3 *); 10089int sqlite3_preupdate_depth(sqlite3 *); 10090int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 10091int sqlite3_preupdate_blobwrite(sqlite3 *); 10092#endif 10093 10094/* 10095** CAPI3REF: Low-level system error code 10096** METHOD: sqlite3 10097** 10098** ^Attempt to return the underlying operating system error code or error 10099** number that caused the most recent I/O error or failure to open a file. 10100** The return value is OS-dependent. For example, on unix systems, after 10101** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 10102** called to get back the underlying "errno" that caused the problem, such 10103** as ENOSPC, EAUTH, EISDIR, and so forth. 10104*/ 10105int sqlite3_system_errno(sqlite3*); 10106 10107/* 10108** CAPI3REF: Database Snapshot 10109** KEYWORDS: {snapshot} {sqlite3_snapshot} 10110** 10111** An instance of the snapshot object records the state of a [WAL mode] 10112** database for some specific point in history. 10113** 10114** In [WAL mode], multiple [database connections] that are open on the 10115** same database file can each be reading a different historical version 10116** of the database file. When a [database connection] begins a read 10117** transaction, that connection sees an unchanging copy of the database 10118** as it existed for the point in time when the transaction first started. 10119** Subsequent changes to the database from other connections are not seen 10120** by the reader until a new read transaction is started. 10121** 10122** The sqlite3_snapshot object records state information about an historical 10123** version of the database file so that it is possible to later open a new read 10124** transaction that sees that historical version of the database rather than 10125** the most recent version. 10126*/ 10127typedef struct sqlite3_snapshot { 10128 unsigned char hidden[48]; 10129} sqlite3_snapshot; 10130 10131/* 10132** CAPI3REF: Record A Database Snapshot 10133** CONSTRUCTOR: sqlite3_snapshot 10134** 10135** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 10136** new [sqlite3_snapshot] object that records the current state of 10137** schema S in database connection D. ^On success, the 10138** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 10139** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 10140** If there is not already a read-transaction open on schema S when 10141** this function is called, one is opened automatically. 10142** 10143** The following must be true for this function to succeed. If any of 10144** the following statements are false when sqlite3_snapshot_get() is 10145** called, SQLITE_ERROR is returned. The final value of *P is undefined 10146** in this case. 10147** 10148** <ul> 10149** <li> The database handle must not be in [autocommit mode]. 10150** 10151** <li> Schema S of [database connection] D must be a [WAL mode] database. 10152** 10153** <li> There must not be a write transaction open on schema S of database 10154** connection D. 10155** 10156** <li> One or more transactions must have been written to the current wal 10157** file since it was created on disk (by any connection). This means 10158** that a snapshot cannot be taken on a wal mode database with no wal 10159** file immediately after it is first opened. At least one transaction 10160** must be written to it first. 10161** </ul> 10162** 10163** This function may also return SQLITE_NOMEM. If it is called with the 10164** database handle in autocommit mode but fails for some other reason, 10165** whether or not a read transaction is opened on schema S is undefined. 10166** 10167** The [sqlite3_snapshot] object returned from a successful call to 10168** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 10169** to avoid a memory leak. 10170** 10171** The [sqlite3_snapshot_get()] interface is only available when the 10172** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10173*/ 10174SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 10175 sqlite3 *db, 10176 const char *zSchema, 10177 sqlite3_snapshot **ppSnapshot 10178); 10179 10180/* 10181** CAPI3REF: Start a read transaction on an historical snapshot 10182** METHOD: sqlite3_snapshot 10183** 10184** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 10185** transaction or upgrades an existing one for schema S of 10186** [database connection] D such that the read transaction refers to 10187** historical [snapshot] P, rather than the most recent change to the 10188** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 10189** on success or an appropriate [error code] if it fails. 10190** 10191** ^In order to succeed, the database connection must not be in 10192** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 10193** is already a read transaction open on schema S, then the database handle 10194** must have no active statements (SELECT statements that have been passed 10195** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 10196** SQLITE_ERROR is returned if either of these conditions is violated, or 10197** if schema S does not exist, or if the snapshot object is invalid. 10198** 10199** ^A call to sqlite3_snapshot_open() will fail to open if the specified 10200** snapshot has been overwritten by a [checkpoint]. In this case 10201** SQLITE_ERROR_SNAPSHOT is returned. 10202** 10203** If there is already a read transaction open when this function is 10204** invoked, then the same read transaction remains open (on the same 10205** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 10206** is returned. If another error code - for example SQLITE_PROTOCOL or an 10207** SQLITE_IOERR error code - is returned, then the final state of the 10208** read transaction is undefined. If SQLITE_OK is returned, then the 10209** read transaction is now open on database snapshot P. 10210** 10211** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 10212** database connection D does not know that the database file for 10213** schema S is in [WAL mode]. A database connection might not know 10214** that the database file is in [WAL mode] if there has been no prior 10215** I/O on that database connection, or if the database entered [WAL mode] 10216** after the most recent I/O on the database connection.)^ 10217** (Hint: Run "[PRAGMA application_id]" against a newly opened 10218** database connection in order to make it ready to use snapshots.) 10219** 10220** The [sqlite3_snapshot_open()] interface is only available when the 10221** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10222*/ 10223SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 10224 sqlite3 *db, 10225 const char *zSchema, 10226 sqlite3_snapshot *pSnapshot 10227); 10228 10229/* 10230** CAPI3REF: Destroy a snapshot 10231** DESTRUCTOR: sqlite3_snapshot 10232** 10233** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 10234** The application must eventually free every [sqlite3_snapshot] object 10235** using this routine to avoid a memory leak. 10236** 10237** The [sqlite3_snapshot_free()] interface is only available when the 10238** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10239*/ 10240SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 10241 10242/* 10243** CAPI3REF: Compare the ages of two snapshot handles. 10244** METHOD: sqlite3_snapshot 10245** 10246** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 10247** of two valid snapshot handles. 10248** 10249** If the two snapshot handles are not associated with the same database 10250** file, the result of the comparison is undefined. 10251** 10252** Additionally, the result of the comparison is only valid if both of the 10253** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 10254** last time the wal file was deleted. The wal file is deleted when the 10255** database is changed back to rollback mode or when the number of database 10256** clients drops to zero. If either snapshot handle was obtained before the 10257** wal file was last deleted, the value returned by this function 10258** is undefined. 10259** 10260** Otherwise, this API returns a negative value if P1 refers to an older 10261** snapshot than P2, zero if the two handles refer to the same database 10262** snapshot, and a positive value if P1 is a newer snapshot than P2. 10263** 10264** This interface is only available if SQLite is compiled with the 10265** [SQLITE_ENABLE_SNAPSHOT] option. 10266*/ 10267SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 10268 sqlite3_snapshot *p1, 10269 sqlite3_snapshot *p2 10270); 10271 10272/* 10273** CAPI3REF: Recover snapshots from a wal file 10274** METHOD: sqlite3_snapshot 10275** 10276** If a [WAL file] remains on disk after all database connections close 10277** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 10278** or because the last process to have the database opened exited without 10279** calling [sqlite3_close()]) and a new connection is subsequently opened 10280** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 10281** will only be able to open the last transaction added to the WAL file 10282** even though the WAL file contains other valid transactions. 10283** 10284** This function attempts to scan the WAL file associated with database zDb 10285** of database handle db and make all valid snapshots available to 10286** sqlite3_snapshot_open(). It is an error if there is already a read 10287** transaction open on the database, or if the database is not a WAL mode 10288** database. 10289** 10290** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 10291** 10292** This interface is only available if SQLite is compiled with the 10293** [SQLITE_ENABLE_SNAPSHOT] option. 10294*/ 10295SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 10296 10297/* 10298** CAPI3REF: Serialize a database 10299** 10300** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 10301** that is a serialization of the S database on [database connection] D. 10302** If P is not a NULL pointer, then the size of the database in bytes 10303** is written into *P. 10304** 10305** For an ordinary on-disk database file, the serialization is just a 10306** copy of the disk file. For an in-memory database or a "TEMP" database, 10307** the serialization is the same sequence of bytes which would be written 10308** to disk if that database where backed up to disk. 10309** 10310** The usual case is that sqlite3_serialize() copies the serialization of 10311** the database into memory obtained from [sqlite3_malloc64()] and returns 10312** a pointer to that memory. The caller is responsible for freeing the 10313** returned value to avoid a memory leak. However, if the F argument 10314** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 10315** are made, and the sqlite3_serialize() function will return a pointer 10316** to the contiguous memory representation of the database that SQLite 10317** is currently using for that database, or NULL if the no such contiguous 10318** memory representation of the database exists. A contiguous memory 10319** representation of the database will usually only exist if there has 10320** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 10321** values of D and S. 10322** The size of the database is written into *P even if the 10323** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 10324** of the database exists. 10325** 10326** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 10327** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 10328** allocation error occurs. 10329** 10330** This interface is omitted if SQLite is compiled with the 10331** [SQLITE_OMIT_DESERIALIZE] option. 10332*/ 10333unsigned char *sqlite3_serialize( 10334 sqlite3 *db, /* The database connection */ 10335 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 10336 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 10337 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 10338); 10339 10340/* 10341** CAPI3REF: Flags for sqlite3_serialize 10342** 10343** Zero or more of the following constants can be OR-ed together for 10344** the F argument to [sqlite3_serialize(D,S,P,F)]. 10345** 10346** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 10347** a pointer to contiguous in-memory database that it is currently using, 10348** without making a copy of the database. If SQLite is not currently using 10349** a contiguous in-memory database, then this option causes 10350** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 10351** using a contiguous in-memory database if it has been initialized by a 10352** prior call to [sqlite3_deserialize()]. 10353*/ 10354#define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 10355 10356/* 10357** CAPI3REF: Deserialize a database 10358** 10359** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 10360** [database connection] D to disconnect from database S and then 10361** reopen S as an in-memory database based on the serialization contained 10362** in P. The serialized database P is N bytes in size. M is the size of 10363** the buffer P, which might be larger than N. If M is larger than N, and 10364** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 10365** permitted to add content to the in-memory database as long as the total 10366** size does not exceed M bytes. 10367** 10368** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 10369** invoke sqlite3_free() on the serialization buffer when the database 10370** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 10371** SQLite will try to increase the buffer size using sqlite3_realloc64() 10372** if writes on the database cause it to grow larger than M bytes. 10373** 10374** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 10375** database is currently in a read transaction or is involved in a backup 10376** operation. 10377** 10378** It is not possible to deserialized into the TEMP database. If the 10379** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the 10380** function returns SQLITE_ERROR. 10381** 10382** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 10383** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 10384** [sqlite3_free()] is invoked on argument P prior to returning. 10385** 10386** This interface is omitted if SQLite is compiled with the 10387** [SQLITE_OMIT_DESERIALIZE] option. 10388*/ 10389int sqlite3_deserialize( 10390 sqlite3 *db, /* The database connection */ 10391 const char *zSchema, /* Which DB to reopen with the deserialization */ 10392 unsigned char *pData, /* The serialized database content */ 10393 sqlite3_int64 szDb, /* Number bytes in the deserialization */ 10394 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 10395 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 10396); 10397 10398/* 10399** CAPI3REF: Flags for sqlite3_deserialize() 10400** 10401** The following are allowed values for 6th argument (the F argument) to 10402** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 10403** 10404** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 10405** in the P argument is held in memory obtained from [sqlite3_malloc64()] 10406** and that SQLite should take ownership of this memory and automatically 10407** free it when it has finished using it. Without this flag, the caller 10408** is responsible for freeing any dynamically allocated memory. 10409** 10410** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 10411** grow the size of the database using calls to [sqlite3_realloc64()]. This 10412** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 10413** Without this flag, the deserialized database cannot increase in size beyond 10414** the number of bytes specified by the M parameter. 10415** 10416** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 10417** should be treated as read-only. 10418*/ 10419#define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 10420#define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 10421#define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 10422 10423/* 10424** Undo the hack that converts floating point types to integer for 10425** builds on processors without floating point support. 10426*/ 10427#ifdef SQLITE_OMIT_FLOATING_POINT 10428# undef double 10429#endif 10430 10431#ifdef __cplusplus 10432} /* End of the 'extern "C"' block */ 10433#endif 10434#endif /* SQLITE3_H */ 10435