text: /* ** 2001 September 15 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the SQLite library ** presents to client programs. If a C-function, structure, datatype, ** or constant definition does not appear in this file, then it is ** not a published API of SQLite, is subject to change without ** notice, and should not be referenced by programs that use SQLite. ** ** Some of the definitions that are in this file are marked as ** "experimental". Experimental interfaces are normally new ** features recently added to SQLite. We do not anticipate changes ** to experimental interfaces but reserve to make minor changes if ** experience from use "in the wild" suggest such changes are prudent. ** ** The official C-language API documentation for SQLite is derived ** from comments in this file. This file is the authoritative source ** on how SQLite interfaces are suppose to operate. ** ** The name of this file under configuration management is "sqlite.h.in". ** The makefile makes some minor changes to this file (such as inserting ** the version number) and changes its name to "sqlite3.h" as ** part of the build process. ** ** @(#) $Id: sqlite.h.in,v 1.292 2008/03/18 13:47:21 drh Exp $ */ #ifndef _SQLITE3_H_ #define _SQLITE3_H_ #include <stdarg.h> /* Needed for the definition of va_list */ /* ** Make sure we can call this stuff from C++. */ #ifdef __cplusplus extern "C" { #endif /* ** Add the ability to override 'extern' */ #ifndef SQLITE_EXTERN # define SQLITE_EXTERN extern #endif /* ** Make sure these symbols where not defined by some previous header ** file. */ #ifdef SQLITE_VERSION # undef SQLITE_VERSION #endif #ifdef SQLITE_VERSION_NUMBER # undef SQLITE_VERSION_NUMBER #endif /* ** CAPI3REF: Compile-Time Library Version Numbers {F10010} ** ** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in ** the sqlite3.h file specify the version of SQLite with which ** that header file is associated. ** ** The "version" of SQLite is a string of the form "X.Y.Z". ** The phrase "alpha" or "beta" might be appended after the Z. ** The X value is major version number always 3 in SQLite3. ** The X value only changes when backwards compatibility is ** broken and we intend to never break ** backwards compatibility. The Y value is the minor version ** number and only changes when ** there are major feature enhancements that are forwards compatible ** but not backwards compatible. The Z value is release number ** and is incremented with ** each release but resets back to 0 when Y is incremented. ** ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()]. ** ** INVARIANTS: ** ** {F10011} The SQLITE_VERSION #define in the sqlite3.h header file ** evaluates to a string literal that is the SQLite version ** with which the header file is associated. ** ** {F10014} The SQLITE_VERSION_NUMBER #define resolves to an integer ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and ** Z are the major version, minor version, and release number. */ #define SQLITE_VERSION "--VERS--" #define SQLITE_VERSION_NUMBER --VERSION-NUMBER-- /* ** CAPI3REF: Run-Time Library Version Numbers {F10020} ** KEYWORDS: sqlite3_version ** ** These features provide the same information as the [SQLITE_VERSION] ** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated ** with the library instead of the header file. Cautious programmers might ** include a check in their application to verify that ** sqlite3_libversion_number() always returns the value ** [SQLITE_VERSION_NUMBER]. ** ** The sqlite3_libversion() function returns the same information as is ** in the sqlite3_version[] string constant. The function is provided ** for use in DLLs since DLL users usually do not have direct access to string ** constants within the DLL. ** ** INVARIANTS: ** ** {F10021} The [sqlite3_libversion_number()] interface returns an integer ** equal to [SQLITE_VERSION_NUMBER]. ** ** {F10022} The [sqlite3_version] string constant contains the text of the ** [SQLITE_VERSION] string. ** ** {F10023} The [sqlite3_libversion()] function returns ** a pointer to the [sqlite3_version] string constant. */ SQLITE_EXTERN const char sqlite3_version[]; const char *sqlite3_libversion(void); int sqlite3_libversion_number(void); /* ** CAPI3REF: Test To See If The Library Is Threadsafe {F10100} ** ** SQLite can be compiled with or without mutexes. When ** the SQLITE_THREADSAFE C preprocessor macro is true, mutexes ** are enabled and SQLite is threadsafe. When that macro is false, ** the mutexes are omitted. Without the mutexes, it is not safe ** to use SQLite from more than one thread. ** ** There is a measurable performance penalty for enabling mutexes. ** So if speed is of utmost importance, it makes sense to disable ** the mutexes. But for maximum safety, mutexes should be enabled. ** The default behavior is for mutexes to be enabled. ** ** This interface can be used by a program to make sure that the ** version of SQLite that it is linking against was compiled with ** the desired setting of the SQLITE_THREADSAFE macro. ** ** INVARIANTS: ** ** {F10101} The [sqlite3_threadsafe()] function returns nonzero if ** SQLite was compiled with its mutexes enabled or zero ** if SQLite was compiled with mutexes disabled. */ int sqlite3_threadsafe(void); /* ** CAPI3REF: Database Connection Handle {F12000} ** KEYWORDS: {database connection} ** ** Each open SQLite database is represented by pointer to an instance of the ** opaque structure named "sqlite3". It is useful to think of an sqlite3 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and ** [sqlite3_open_v2()] interfaces are its constructors ** and [sqlite3_close()] is its destructor. There are many other interfaces ** (such as [sqlite3_prepare_v2()], [sqlite3_create_function()], and ** [sqlite3_busy_timeout()] to name but three) that are methods on this ** object. */ typedef struct sqlite3 sqlite3; /* ** CAPI3REF: 64-Bit Integer Types {F10200} ** KEYWORDS: sqlite_int64 sqlite_uint64 ** ** Because there is no cross-platform way to specify 64-bit integer types ** SQLite includes typedefs for 64-bit signed and unsigned integers. ** ** The sqlite3_int64 and sqlite3_uint64 are the preferred type ** definitions. The sqlite_int64 and sqlite_uint64 types are ** supported for backwards compatibility only. ** ** INVARIANTS: ** ** {F10201} The [sqlite_int64] and [sqlite3_int64] types specify a ** 64-bit signed integer. ** ** {F10202} The [sqlite_uint64] and [sqlite3_uint64] types specify ** a 64-bit unsigned integer. */ #ifdef SQLITE_INT64_TYPE typedef SQLITE_INT64_TYPE sqlite_int64; typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; #elif defined(_MSC_VER) || defined(__BORLANDC__) typedef __int64 sqlite_int64; typedef unsigned __int64 sqlite_uint64; #else typedef long long int sqlite_int64; typedef unsigned long long int sqlite_uint64; #endif typedef sqlite_int64 sqlite3_int64; typedef sqlite_uint64 sqlite3_uint64; /* ** If compiling for a processor that lacks floating point support, ** substitute integer for floating-point */ #ifdef SQLITE_OMIT_FLOATING_POINT # define double sqlite3_int64 #endif /* ** CAPI3REF: Closing A Database Connection {F12010} ** ** This routine is the destructor for the [sqlite3] object. ** ** Applications should [sqlite3_finalize | finalize] all ** [prepared statements] and ** [sqlite3_blob_close | close] all [sqlite3_blob | BLOBs] ** associated with the [sqlite3] object prior ** to attempting to close the [sqlite3] object. ** ** <todo>What happens to pending transactions? Are they ** rolled back, or abandoned?</todo> ** ** INVARIANTS: ** ** {F12011} The [sqlite3_close()] interface destroys an [sqlite3] object ** allocated by a prior call to [sqlite3_open()], ** [sqlite3_open16()], or [sqlite3_open_v2()]. ** ** {F12012} The [sqlite3_close()] function releases all memory used by the ** connection and closes all open files. ** ** {F12013} If the database connection contains ** [prepared statements] that have not been ** finalized by [sqlite3_finalize()], then [sqlite3_close()] ** returns [SQLITE_BUSY] and leaves the connection open. ** ** {F12014} Giving sqlite3_close() a NULL pointer is a harmless no-op. ** ** LIMITATIONS: ** ** {U12015} The parameter to [sqlite3_close()] must be an [sqlite3] object ** pointer previously obtained from [sqlite3_open()] or the ** equivalent, or NULL. ** ** {U12016} The parameter to [sqlite3_close()] must not have been previously ** closed. */ int sqlite3_close(sqlite3 *); /* ** The type for a callback function. ** This is legacy and deprecated. It is included for historical ** compatibility and is not documented. */ typedef int (*sqlite3_callback)(void*,int,char**, char**); /* ** CAPI3REF: One-Step Query Execution Interface {F12100} ** ** The sqlite3_exec() interface is a convenient way of running ** one or more SQL statements without a lot of C code. The ** SQL statements are passed in as the second parameter to ** sqlite3_exec(). The statements are evaluated one by one ** until either an error or an interrupt is encountered or ** until they are all done. The 3rd parameter is an optional ** callback that is invoked once for each row of any query results ** produced by the SQL statements. The 5th parameter tells where ** to write any error messages. ** ** The sqlite3_exec() interface is implemented in terms of ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. ** The sqlite3_exec() routine does nothing that cannot be done ** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. ** The sqlite3_exec() is just a convenient wrapper. ** ** INVARIANTS: ** ** {F12101} The [sqlite3_exec()] interface evaluates zero or more UTF-8 ** encoded, semicolon-separated, SQL statements in the ** zero-terminated string of its 2nd parameter within the ** context of the [sqlite3] object given in the 1st parameter. ** ** {F12104} The return value of [sqlite3_exec()] is SQLITE_OK if all ** SQL statements run successfully. ** ** {F12105} The return value of [sqlite3_exec()] is an appropriate ** non-zero error code if any SQL statement fails. ** ** {F12107} If one or more of the SQL statements handed to [sqlite3_exec()] ** return results and the 3rd parameter is not NULL, then ** the callback function specified by the 3rd parameter is ** invoked once for each row of result. ** ** {F12110} If the callback returns a non-zero value then [sqlite3_exec()] ** will aborted the SQL statement it is currently evaluating, ** skip all subsequent SQL statements, and return [SQLITE_ABORT]. ** <todo>What happens to *errmsg here? Does the result code for ** sqlite3_errcode() get set?</todo> ** ** {F12113} The [sqlite3_exec()] routine will pass its 4th parameter through ** as the 1st parameter of the callback. ** ** {F12116} The [sqlite3_exec()] routine sets the 2nd parameter of its ** callback to be the number of columns in the current row of ** result. ** ** {F12119} The [sqlite3_exec()] routine sets the 3rd parameter of its ** callback to be an array of pointers to strings holding the ** values for each column in the current result set row as ** obtained from [sqlite3_column_text()]. ** ** {F12122} The [sqlite3_exec()] routine sets the 4th parameter of its ** callback to be an array of pointers to strings holding the ** names of result columns as obtained from [sqlite3_column_name()]. ** ** {F12125} If the 3rd parameter to [sqlite3_exec()] is NULL then ** [sqlite3_exec()] never invokes a callback. All query ** results are silently discarded. ** ** {F12128} If an error occurs while parsing or evaluating any of the SQL ** statements handed to [sqlite3_exec()] then [sqlite3_exec()] will ** return an [error code] other than [SQLITE_OK]. ** ** {F12131} If an error occurs while parsing or evaluating any of the SQL ** handed to [sqlite3_exec()] and if the 5th parameter (errmsg) ** to [sqlite3_exec()] is not NULL, then an error message is ** allocated using the equivalent of [sqlite3_mprintf()] and ** *errmsg is made to point to that message. ** ** {F12134} The [sqlite3_exec()] routine does not change the value of ** *errmsg if errmsg is NULL or if there are no errors. ** ** {F12137} The [sqlite3_exec()] function sets the error code and message ** accessible via [sqlite3_errcode()], [sqlite3_errmsg()], and ** [sqlite3_errmsg16()]. ** ** LIMITATIONS: ** ** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open ** [database connection]. ** ** {U12142} The database connection must not be closed while ** [sqlite3_exec()] is running. ** ** {U12143} The calling function is should use [sqlite3_free()] to free ** the memory that *errmsg is left pointing at once the error ** message is no longer needed. ** ** {U12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()] ** must remain unchanged while [sqlite3_exec()] is running. */ int sqlite3_exec( sqlite3*, /* An open database */ const char *sql, /* SQL to be evaluted */ int (*callback)(void*,int,char**,char**), /* Callback function */ void *, /* 1st argument to callback */ char **errmsg /* Error msg written here */ ); /* ** CAPI3REF: Result Codes {F10210} ** KEYWORDS: SQLITE_OK {error code} {error codes} ** ** Many SQLite functions return an integer result code from the set shown ** here in order to indicates success or failure. ** ** See also: [SQLITE_IOERR_READ | extended result codes] */ #define SQLITE_OK 0 /* Successful result */ /* beginning-of-error-codes */ #define SQLITE_ERROR 1 /* SQL error or missing database */ #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ #define SQLITE_PERM 3 /* Access permission denied */ #define SQLITE_ABORT 4 /* Callback routine requested an abort */ #define SQLITE_BUSY 5 /* The database file is locked */ #define SQLITE_LOCKED 6 /* A table in the database is locked */ #define SQLITE_NOMEM 7 /* A malloc() failed */ #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ #define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */ #define SQLITE_FULL 13 /* Insertion failed because database is full */ #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ #define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */ #define SQLITE_EMPTY 16 /* Database is empty */ #define SQLITE_SCHEMA 17 /* The database schema changed */ #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ #define SQLITE_MISMATCH 20 /* Data type mismatch */ #define SQLITE_MISUSE 21 /* Library used incorrectly */ #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ #define SQLITE_AUTH 23 /* Authorization denied */ #define SQLITE_FORMAT 24 /* Auxiliary database format error */ #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ #define SQLITE_NOTADB 26 /* File opened that is not a database file */ #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ /* end-of-error-codes */ /* ** CAPI3REF: Extended Result Codes {F10220} ** KEYWORDS: {extended error code} {extended error codes} ** KEYWORDS: {extended result codes} ** ** In its default configuration, SQLite API routines return one of 26 integer ** [SQLITE_OK | result codes]. However, experience has shown that ** many of these result codes are too course-grained. They do not provide as ** much information about problems as programmers might like. In an effort to ** address this, newer versions of SQLite (version 3.3.8 and later) include ** support for additional result codes that provide more detailed information ** about errors. The extended result codes are enabled or disabled ** for each database connection using the [sqlite3_extended_result_codes()] ** API. ** ** Some of the available extended result codes are listed here. ** One may expect the number of extended result codes will be expand ** over time. Software that uses extended result codes should expect ** to see new result codes in future releases of SQLite. ** ** The SQLITE_OK result code will never be extended. It will always ** be exactly zero. ** ** INVARIANTS: ** ** {F10223} The symbolic name for an extended result code always contains ** a related primary result code as a prefix. ** ** {F10224} Primary result code names contain a single "_" character. ** ** {F10225} Extended result code names contain two or more "_" characters. ** ** {F10226} The numeric value of an extended result code contains the ** numeric value of its corresponding primary result code in ** its least significant 8 bits. */ #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) /* ** CAPI3REF: Flags For File Open Operations {F10230} ** ** These bit values are intended for use in the ** 3rd parameter to the [sqlite3_open_v2()] interface and ** in the 4th parameter to the xOpen method of the ** [sqlite3_vfs] object. */ #define SQLITE_OPEN_READONLY 0x00000001 #define SQLITE_OPEN_READWRITE 0x00000002 #define SQLITE_OPEN_CREATE 0x00000004 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 #define SQLITE_OPEN_MAIN_DB 0x00000100 #define SQLITE_OPEN_TEMP_DB 0x00000200 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* ** CAPI3REF: Device Characteristics {F10240} ** ** The xDeviceCapabilities method of the [sqlite3_io_methods] ** object returns an integer which is a vector of the these ** bit values expressing I/O characteristics of the mass storage ** device that holds the file that the [sqlite3_io_methods] ** refers to. ** ** The SQLITE_IOCAP_ATOMIC property means that all writes of ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values ** mean that writes of blocks that are nnn bytes in size and ** are aligned to an address which is an integer multiple of ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means ** that when data is appended to a file, the data is appended ** first then the size of the file is extended, never the other ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that ** information is written to disk in the same order as calls ** to xWrite(). */ #define SQLITE_IOCAP_ATOMIC 0x00000001 #define SQLITE_IOCAP_ATOMIC512 0x00000002 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 /* ** CAPI3REF: File Locking Levels {F10250} ** ** SQLite uses one of these integer values as the second ** argument to calls it makes to the xLock() and xUnlock() methods ** of an [sqlite3_io_methods] object. */ #define SQLITE_LOCK_NONE 0 #define SQLITE_LOCK_SHARED 1 #define SQLITE_LOCK_RESERVED 2 #define SQLITE_LOCK_PENDING 3 #define SQLITE_LOCK_EXCLUSIVE 4 /* ** CAPI3REF: Synchronization Type Flags {F10260} ** ** When SQLite invokes the xSync() method of an ** [sqlite3_io_methods] object it uses a combination of ** these integer values as the second argument. ** ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the ** sync operation only needs to flush data to mass storage. Inode ** information need not be flushed. The SQLITE_SYNC_NORMAL flag means ** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means ** to use Mac OS-X style fullsync instead of fsync(). */ #define SQLITE_SYNC_NORMAL 0x00002 #define SQLITE_SYNC_FULL 0x00003 #define SQLITE_SYNC_DATAONLY 0x00010 /* ** CAPI3REF: OS Interface Open File Handle {F11110} ** ** An [sqlite3_file] object represents an open file in the OS ** interface layer. Individual OS interface implementations will ** want to subclass this object by appending additional fields ** for their own use. The pMethods entry is a pointer to an ** [sqlite3_io_methods] object that defines methods for performing ** I/O operations on the open file. */ typedef struct sqlite3_file sqlite3_file; struct sqlite3_file { const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ }; /* ** CAPI3REF: OS Interface File Virtual Methods Object {F11120} ** ** Every file opened by the [sqlite3_vfs] xOpen method contains a pointer to ** an instance of this object. This object defines the ** methods used to perform various operations against the open file. ** ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). * The second choice is an ** OS-X style fullsync. The SQLITE_SYNC_DATA flag may be ORed in to ** indicate that only the data of the file and not its inode needs to be ** synced. ** ** The integer values to xLock() and xUnlock() are one of ** <ul> ** <li> [SQLITE_LOCK_NONE], ** <li> [SQLITE_LOCK_SHARED], ** <li> [SQLITE_LOCK_RESERVED], ** <li> [SQLITE_LOCK_PENDING], or ** <li> [SQLITE_LOCK_EXCLUSIVE]. ** </ul> ** xLock() increases the lock. xUnlock() decreases the lock. ** The xCheckReservedLock() method looks ** to see if any database connection, either in this ** process or in some other process, is holding an RESERVED, ** PENDING, or EXCLUSIVE lock on the file. It returns true ** if such a lock exists and false if not. ** ** The xFileControl() method is a generic interface that allows custom ** VFS implementations to directly control an open file using the ** [sqlite3_file_control()] interface. The second "op" argument ** is an integer opcode. The third ** argument is a generic pointer which is intended to be a pointer ** to a structure that may contain arguments or space in which to ** write return values. Potential uses for xFileControl() might be ** functions to enable blocking locks with timeouts, to change the ** locking strategy (for example to use dot-file locks), to inquire ** about the status of a lock, or to break stale locks. The SQLite ** core reserves opcodes less than 100 for its own use. ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available. ** Applications that define a custom xFileControl method should use opcodes ** greater than 100 to avoid conflicts. ** ** The xSectorSize() method returns the sector size of the ** device that underlies the file. The sector size is the ** minimum write that can be performed without disturbing ** other bytes in the file. The xDeviceCharacteristics() ** method returns a bit vector describing behaviors of the ** underlying device: ** ** <ul> ** <li> [SQLITE_IOCAP_ATOMIC] ** <li> [SQLITE_IOCAP_ATOMIC512] ** <li> [SQLITE_IOCAP_ATOMIC1K] ** <li> [SQLITE_IOCAP_ATOMIC2K] ** <li> [SQLITE_IOCAP_ATOMIC4K] ** <li> [SQLITE_IOCAP_ATOMIC8K] ** <li> [SQLITE_IOCAP_ATOMIC16K] ** <li> [SQLITE_IOCAP_ATOMIC32K] ** <li> [SQLITE_IOCAP_ATOMIC64K] ** <li> [SQLITE_IOCAP_SAFE_APPEND] ** <li> [SQLITE_IOCAP_SEQUENTIAL] ** </ul> ** ** The SQLITE_IOCAP_ATOMIC property means that all writes of ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values ** mean that writes of blocks that are nnn bytes in size and ** are aligned to an address which is an integer multiple of ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means ** that when data is appended to a file, the data is appended ** first then the size of the file is extended, never the other ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that ** information is written to disk in the same order as calls ** to xWrite(). */ typedef struct sqlite3_io_methods sqlite3_io_methods; struct sqlite3_io_methods { int iVersion; int (*xClose)(sqlite3_file*); int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); int (*xSync)(sqlite3_file*, int flags); int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); int (*xLock)(sqlite3_file*, int); int (*xUnlock)(sqlite3_file*, int); int (*xCheckReservedLock)(sqlite3_file*); int (*xFileControl)(sqlite3_file*, int op, void *pArg); int (*xSectorSize)(sqlite3_file*); int (*xDeviceCharacteristics)(sqlite3_file*); /* Additional methods may be added in future releases */ }; /* ** CAPI3REF: Standard File Control Opcodes {F11310} ** ** These integer constants are opcodes for the xFileControl method ** of the [sqlite3_io_methods] object and to the [sqlite3_file_control()] ** interface. ** ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This ** opcode causes the xFileControl method to write the current state of ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) ** into an integer that the pArg argument points to. This capability ** is used during testing and only needs to be supported when SQLITE_TEST ** is defined. */ #define SQLITE_FCNTL_LOCKSTATE 1 /* ** CAPI3REF: Mutex Handle {F17110} ** ** The mutex module within SQLite defines [sqlite3_mutex] to be an ** abstract type for a mutex object. The SQLite core never looks ** at the internal representation of an [sqlite3_mutex]. It only ** deals with pointers to the [sqlite3_mutex] object. ** ** Mutexes are created using [sqlite3_mutex_alloc()]. */ typedef struct sqlite3_mutex sqlite3_mutex; /* ** CAPI3REF: OS Interface Object {F11140} ** ** An instance of this object defines the interface between the ** SQLite core and the underlying operating system. The "vfs" ** in the name of the object stands for "virtual file system". ** ** The iVersion field is initially 1 but may be larger for future ** versions of SQLite. Additional fields may be appended to this ** object when the iVersion value is increased. ** ** The szOsFile field is the size of the subclassed [sqlite3_file] ** structure used by this VFS. mxPathname is the maximum length of ** a pathname in this VFS. ** ** Registered sqlite3_vfs objects are kept on a linked list formed by ** the pNext pointer. The [sqlite3_vfs_register()] ** and [sqlite3_vfs_unregister()] interfaces manage this list ** in a thread-safe way. The [sqlite3_vfs_find()] interface ** searches the list. ** ** The pNext field is the only field in the sqlite3_vfs ** structure that SQLite will ever modify. SQLite will only access ** or modify this field while holding a particular static mutex. ** The application should never modify anything within the sqlite3_vfs ** object once the object has been registered. ** ** The zName field holds the name of the VFS module. The name must ** be unique across all VFS modules. ** ** {F11141} SQLite will guarantee that the zFilename string passed to ** xOpen() is a full pathname as generated by xFullPathname() and ** that the string will be valid and unchanged until xClose() is ** called. {END} So the [sqlite3_file] can store a pointer to the ** filename if it needs to remember the filename for some reason. ** ** {F11142} The flags argument to xOpen() includes all bits set in ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] ** or [sqlite3_open16()] is used, then flags includes at least ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END} ** If xOpen() opens a file read-only then it sets *pOutFlags to ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be ** set. ** ** {F11143} SQLite will also add one of the following flags to the xOpen() ** call, depending on the object being opened: ** ** <ul> ** <li> [SQLITE_OPEN_MAIN_DB] ** <li> [SQLITE_OPEN_MAIN_JOURNAL] ** <li> [SQLITE_OPEN_TEMP_DB] ** <li> [SQLITE_OPEN_TEMP_JOURNAL] ** <li> [SQLITE_OPEN_TRANSIENT_DB] ** <li> [SQLITE_OPEN_SUBJOURNAL] ** <li> [SQLITE_OPEN_MASTER_JOURNAL] ** </ul> {END} ** ** The file I/O implementation can use the object type flags to ** changes the way it deals with files. For example, an application ** that does not care about crash recovery or rollback might make ** the open of a journal file a no-op. Writes to this journal would ** also be no-ops, and any attempt to read the journal would return ** SQLITE_IOERR. Or the implementation might recognize that a database ** file will be doing page-aligned sector reads and writes in a random ** order and set up its I/O subsystem accordingly. ** ** SQLite might also add one of the following flags to the xOpen ** method: ** ** <ul> ** <li> [SQLITE_OPEN_DELETEONCLOSE] ** <li> [SQLITE_OPEN_EXCLUSIVE] ** </ul> ** ** {F11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be ** deleted when it is closed. {F11146} The [SQLITE_OPEN_DELETEONCLOSE] ** will be set for TEMP databases, journals and for subjournals. ** {F11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened ** for exclusive access. This flag is set for all files except ** for the main database file. {END} ** ** {F11148} At least szOsFile bytes of memory are allocated by SQLite ** to hold the [sqlite3_file] structure passed as the third ** argument to xOpen. {END} The xOpen method does not have to ** allocate the structure; it should just fill it in. ** ** {F11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] ** to test for the existance of a file, ** or [SQLITE_ACCESS_READWRITE] to test to see ** if a file is readable and writable, or [SQLITE_ACCESS_READ] ** to test to see if a file is at least readable. {END} The file can be a ** directory. ** ** {F11150} SQLite will always allocate at least mxPathname+1 bytes for ** the output buffers for xGetTempname and xFullPathname. {F11151} The exact ** size of the output buffer is also passed as a parameter to both ** methods. {END} If the output buffer is not large enough, SQLITE_CANTOPEN ** should be returned. As this is handled as a fatal error by SQLite, ** vfs implementations should endeavor to prevent this by setting ** mxPathname to a sufficiently large value. ** ** The xRandomness(), xSleep(), and xCurrentTime() interfaces ** are not strictly a part of the filesystem, but they are ** included in the VFS structure for completeness. ** The xRandomness() function attempts to return nBytes bytes ** of good-quality randomness into zOut. The return value is ** the actual number of bytes of randomness obtained. The ** xSleep() method causes the calling thread to sleep for at ** least the number of microseconds given. The xCurrentTime() ** method returns a Julian Day Number for the current date and ** time. */ typedef struct sqlite3_vfs sqlite3_vfs; struct sqlite3_vfs { int iVersion; /* Structure version number */ int szOsFile; /* Size of subclassed sqlite3_file */ int mxPathname; /* Maximum file pathname length */ sqlite3_vfs *pNext; /* Next registered VFS */ const char *zName; /* Name of this virtual file system */ void *pAppData; /* Pointer to application-specific data */ int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, int flags, int *pOutFlags); int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); int (*xAccess)(sqlite3_vfs*, const char *zName, int flags); int (*xGetTempname)(sqlite3_vfs*, int nOut, char *zOut); int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol); void (*xDlClose)(sqlite3_vfs*, void*); int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); int (*xSleep)(sqlite3_vfs*, int microseconds); int (*xCurrentTime)(sqlite3_vfs*, double*); /* New fields may be appended in figure versions. The iVersion ** value will increment whenever this happens. */ }; /* ** CAPI3REF: Flags for the xAccess VFS method {F11190} ** ** {F11191} These integer constants can be used as the third parameter to ** the xAccess method of an [sqlite3_vfs] object. {END} They determine ** what kind of permissions the xAccess method is ** looking for. {F11192} With SQLITE_ACCESS_EXISTS, the xAccess method ** simply checks to see if the file exists. {F11193} With ** SQLITE_ACCESS_READWRITE, the xAccess method checks to see ** if the file is both readable and writable. {F11194} With ** SQLITE_ACCESS_READ the xAccess method ** checks to see if the file is readable. */ #define SQLITE_ACCESS_EXISTS 0 #define SQLITE_ACCESS_READWRITE 1 #define SQLITE_ACCESS_READ 2 /* ** CAPI3REF: Enable Or Disable Extended Result Codes {F12200} ** ** The sqlite3_extended_result_codes() routine enables or disables the ** [SQLITE_IOERR_READ | extended result codes] feature of SQLite. ** The extended result codes are disabled by default for historical ** compatibility. ** ** INVARIANTS: ** ** {F12201} Each new [database connection] has the ** [extended result codes] feature ** disabled by default. ** ** {F12202} The [sqlite3_extended_result_codes(D,F)] interface will enable ** [extended result codes] for the ** [database connection] D if the F parameter ** is true, or disable them if F is false. */ int sqlite3_extended_result_codes(sqlite3*, int onoff); /* ** CAPI3REF: Last Insert Rowid {F12220} ** ** Each entry in an SQLite table has a unique 64-bit signed ** integer key called the "rowid". The rowid is always available ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those ** names are not also used by explicitly declared columns. If ** the table has a column of type INTEGER PRIMARY KEY then that column ** is another alias for the rowid. ** ** This routine returns the rowid of the most recent ** successful INSERT into the database from the database connection ** shown in the first argument. If no successful inserts ** have ever occurred on this database connection, zero is returned. ** ** If an INSERT occurs within a trigger, then the rowid of the ** inserted row is returned by this routine as long as the trigger ** is running. But once the trigger terminates, the value returned ** by this routine reverts to the last value inserted before the ** trigger fired. ** ** An INSERT that fails due to a constraint violation is not a ** successful insert and does not change the value returned by this ** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, ** and INSERT OR ABORT make no changes to the return value of this ** routine when their insertion fails. When INSERT OR REPLACE ** encounters a constraint violation, it does not fail. The ** INSERT continues to completion after deleting rows that caused ** the constraint problem so INSERT OR REPLACE will always change ** the return value of this interface. ** ** For the purposes of this routine, an insert is considered to ** be successful even if it is subsequently rolled back. ** ** INVARIANTS: ** ** {F12221} The [sqlite3_last_insert_rowid()] function returns the ** rowid of the most recent successful insert done ** on the same database connection and within the same ** trigger context, or zero if there have ** been no qualifying inserts on that connection. ** ** {F12223} The [sqlite3_last_insert_rowid()] function returns ** same value when called from the same trigger context ** immediately before and after a ROLLBACK. ** ** LIMITATIONS: ** ** {U12232} If a separate thread does a new insert on the same ** database connection while the [sqlite3_last_insert_rowid()] ** function is running and thus changes the last insert rowid, ** then the value returned by [sqlite3_last_insert_rowid()] is ** unpredictable and might not equal either the old or the new ** last insert rowid. */ sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); /* ** CAPI3REF: Count The Number Of Rows Modified {F12240} ** ** This function returns the number of database rows that were changed ** or inserted or deleted by the most recently completed SQL statement ** on the connection specified by the first parameter. Only ** changes that are directly specified by the INSERT, UPDATE, or ** DELETE statement are counted. Auxiliary changes caused by ** triggers are not counted. Use the [sqlite3_total_changes()] function ** to find the total number of changes including changes caused by triggers. ** ** A "row change" is a change to a single row of a single table ** caused by an INSERT, DELETE, or UPDATE statement. Rows that ** are changed as side effects of REPLACE constraint resolution, ** rollback, ABORT processing, DROP TABLE, or by any other ** mechanisms do not count as direct row changes. ** ** A "trigger context" is a scope of execution that begins and ** ends with the script of a trigger. Most SQL statements are ** evaluated outside of any trigger. This is the "top level" ** trigger context. If a trigger fires from the top level, a ** new trigger context is entered for the duration of that one ** trigger. Subtriggers create subcontexts for their duration. ** ** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does ** not create a new trigger context. ** ** This function returns the number of direct row changes in the ** most recent INSERT, UPDATE, or DELETE statement within the same ** trigger context. ** ** So when called from the top level, this function returns the ** number of changes in the most recent INSERT, UPDATE, or DELETE ** that also occurred at the top level. ** Within the body of a trigger, the sqlite3_changes() interface ** can be called to find the number of ** changes in the most recently completed INSERT, UPDATE, or DELETE ** statement within the body of the same trigger. ** However, the number returned does not include in changes ** caused by subtriggers since they have their own context. ** ** SQLite implements the command "DELETE FROM table" without ** a WHERE clause by dropping and recreating the table. (This is much ** faster than going through and deleting individual elements from the ** table.) Because of this optimization, the deletions in ** "DELETE FROM table" are not row changes and will not be counted ** by the sqlite3_changes() or [sqlite3_total_changes()] functions. ** To get an accurate count of the number of rows deleted, use ** "DELETE FROM table WHERE 1" instead. ** ** INVARIANTS: ** ** {F12241} The [sqlite3_changes()] function returns the number of ** row changes caused by the most recent INSERT, UPDATE, ** or DELETE statement on the same database connection and ** within the same trigger context, or zero if there have ** not been any qualifying row changes. ** ** LIMITATIONS: ** ** {U12252} If a separate thread makes changes on the same database connection ** while [sqlite3_changes()] is running then the value returned ** is unpredictable and unmeaningful. */ int sqlite3_changes(sqlite3*); /* ** CAPI3REF: Total Number Of Rows Modified {F12260} *** ** This function returns the number of row changes caused ** by INSERT, UPDATE or DELETE statements since the database handle ** was opened. The count includes all changes from all trigger ** contexts. But the count does not include changes used to ** implement REPLACE constraints, do rollbacks or ABORT processing, ** or DROP table processing. ** The changes ** are counted as soon as the statement that makes them is completed ** (when the statement handle is passed to [sqlite3_reset()] or ** [sqlite3_finalize()]). ** ** SQLite implements the command "DELETE FROM table" without ** a WHERE clause by dropping and recreating the table. (This is much ** faster than going ** through and deleting individual elements from the table.) Because of ** this optimization, the change count for "DELETE FROM table" will be ** zero regardless of the number of elements that were originally in the ** table. To get an accurate count of the number of rows deleted, use ** "DELETE FROM table WHERE 1" instead. ** ** See also the [sqlite3_changes()] interface. ** ** INVARIANTS: ** ** {F12261} The [sqlite3_total_changes()] returns the total number ** of row changes caused by INSERT, UPDATE, and/or DELETE ** statements on the same [database connection], in any ** trigger context, since the database connection was ** created. ** ** LIMITATIONS: ** ** {U12264} If a separate thread makes changes on the same database connection ** while [sqlite3_total_changes()] is running then the value ** returned is unpredictable and unmeaningful. */ int sqlite3_total_changes(sqlite3*); /* ** CAPI3REF: Interrupt A Long-Running Query {F12270} ** ** This function causes any pending database operation to abort and ** return at its earliest opportunity. This routine is typically ** called in response to a user action such as pressing "Cancel" ** or Ctrl-C where the user wants a long query operation to halt ** immediately. ** ** It is safe to call this routine from a thread different from the ** thread that is currently running the database operation. But it ** is not safe to call this routine with a database connection that ** is closed or might close before sqlite3_interrupt() returns. ** ** If an SQL is very nearly finished at the time when sqlite3_interrupt() ** is called, then it might not have an opportunity to be interrupted. ** It might continue to completion. ** An SQL operation that is interrupted will return ** [SQLITE_INTERRUPT]. If the interrupted SQL operation is an ** INSERT, UPDATE, or DELETE that is inside an explicit transaction, ** then the entire transaction will be rolled back automatically. ** A call to sqlite3_interrupt() has no effect on SQL statements ** that are started after sqlite3_interrupt() returns. ** ** INVARIANTS: ** ** {F12271} The [sqlite3_interrupt()] interface will force all running ** SQL statements associated with the same database connection ** to halt after processing at most one additional row of ** data. ** ** {F12272} Any SQL statement that is interrupted by [sqlite3_interrupt()] ** will return [SQLITE_INTERRUPT]. ** ** LIMITATIONS: ** ** {U12279} If the database connection closes while [sqlite3_interrupt()] ** is running then bad things will likely happen. */ void sqlite3_interrupt(sqlite3*); /* ** CAPI3REF: Determine If An SQL Statement Is Complete {F10510} ** ** These routines are useful for command-line input to determine if the ** currently entered text seems to form complete a SQL statement or ** if additional input is needed before sending the text into ** SQLite for parsing. These routines return true if the input string ** appears to be a complete SQL statement. A statement is judged to be ** complete if it ends with a semicolon token and is not a fragment of a ** CREATE TRIGGER statement. Semicolons that are embedded within ** string literals or quoted identifier names or comments are not ** independent tokens (they are part of the token in which they are ** embedded) and thus do not count as a statement terminator. ** ** These routines do not parse the SQL and ** so will not detect syntactically incorrect SQL. ** ** INVARIANTS: ** ** {F10511} The sqlite3_complete() and sqlite3_complete16() functions ** return true (non-zero) if and only if the last ** non-whitespace token in their input is a semicolon that ** is not in between the BEGIN and END of a CREATE TRIGGER ** statement. ** ** LIMITATIONS: ** ** {U10512} The input to sqlite3_complete() must be a zero-terminated ** UTF-8 string. ** ** {U10513} The input to sqlite3_complete16() must be a zero-terminated ** UTF-16 string in native byte order. */ int sqlite3_complete(const char *sql); int sqlite3_complete16(const void *sql); /* ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {F12310} ** ** This routine identifies a callback function that might be ** invoked whenever an attempt is made to open a database table ** that another thread or process has locked. ** If the busy callback is NULL, then [SQLITE_BUSY] ** or [SQLITE_IOERR_BLOCKED] ** is returned immediately upon encountering the lock. ** If the busy callback is not NULL, then the ** callback will be invoked with two arguments. The ** first argument to the handler is a copy of the void* pointer which ** is the third argument to this routine. The second argument to ** the handler is the number of times that the busy handler has ** been invoked for this locking event. If the ** busy callback returns 0, then no additional attempts are made to ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned. ** If the callback returns non-zero, then another attempt ** is made to open the database for reading and the cycle repeats. ** ** The presence of a busy handler does not guarantee that ** it will be invoked when there is lock contention. ** If SQLite determines that invoking the busy handler could result in ** a deadlock, it will go ahead and return [SQLITE_BUSY] or ** [SQLITE_IOERR_BLOCKED] instead of invoking the ** busy handler. ** Consider a scenario where one process is holding a read lock that ** it is trying to promote to a reserved lock and ** a second process is holding a reserved lock that it is trying ** to promote to an exclusive lock. The first process cannot proceed ** because it is blocked by the second and the second process cannot ** proceed because it is blocked by the first. If both processes ** invoke the busy handlers, neither will make any progress. Therefore, ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this ** will induce the first process to release its read lock and allow ** the second process to proceed. ** ** The default busy callback is NULL. ** ** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] ** when SQLite is in the middle of a large transaction where all the ** changes will not fit into the in-memory cache. SQLite will ** already hold a RESERVED lock on the database file, but it needs ** to promote this lock to EXCLUSIVE so that it can spill cache ** pages into the database file without harm to concurrent ** readers. If it is unable to promote the lock, then the in-memory ** cache will be left in an inconsistent state and so the error ** code is promoted from the relatively benign [SQLITE_BUSY] to ** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion ** forces an automatic rollback of the changes. See the ** <a href="http://www.sqlite.org/cvstrac/wiki?p=CorruptionFollowingBusyError"> ** CorruptionFollowingBusyError</a> wiki page for a discussion of why ** this is important. ** ** There can only be a single busy handler defined for each database ** connection. Setting a new busy handler clears any previous one. ** Note that calling [sqlite3_busy_timeout()] will also set or clear ** the busy handler. ** ** INVARIANTS: ** ** {F12311} The [sqlite3_busy_handler()] function replaces the busy handler ** callback in the database connection identified by the 1st ** parameter with a new busy handler identified by the 2nd and 3rd ** parameters. ** ** {F12312} The default busy handler for new database connections is NULL. ** ** {F12314} When two or more database connection share a common cache, ** the busy handler for the database connection currently using ** the cache is invoked when the cache encounters a lock. ** ** {F12316} If a busy handler callback returns zero, then the SQLite ** interface that provoked the locking event will return ** [SQLITE_BUSY]. ** ** {F12318} SQLite will invokes the busy handler with two argument which ** are a copy of the pointer supplied by the 3rd parameter to ** [sqlite3_busy_handler()] and a count of the number of prior ** invocations of the busy handler for the same locking event. ** ** LIMITATIONS: ** ** {U12319} A busy handler should not call close the database connection ** or prepared statement that invoked the busy handler. */ int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); /* ** CAPI3REF: Set A Busy Timeout {F12340} ** ** This routine sets a [sqlite3_busy_handler | busy handler] ** that sleeps for a while when a ** table is locked. The handler will sleep multiple times until ** at least "ms" milliseconds of sleeping have been done. {F12343} After ** "ms" milliseconds of sleeping, the handler returns 0 which ** causes [sqlite3_step()] to return [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. ** ** Calling this routine with an argument less than or equal to zero ** turns off all busy handlers. ** ** There can only be a single busy handler for a particular database ** connection. If another busy handler was defined ** (using [sqlite3_busy_handler()]) prior to calling ** this routine, that other busy handler is cleared. ** ** INVARIANTS: ** ** {F12341} The [sqlite3_busy_timeout()] function overrides any prior ** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting ** on the same database connection. ** ** {F12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than ** or equal to zero, then the busy handler is cleared so that ** all subsequent locking events immediately return [SQLITE_BUSY]. ** ** {F12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive ** number N, then a busy handler is set that repeatedly calls ** the xSleep() method in the VFS interface until either the ** lock clears or until the cumulative sleep time reported back ** by xSleep() exceeds N milliseconds. */ int sqlite3_busy_timeout(sqlite3*, int ms); /* ** CAPI3REF: Convenience Routines For Running Queries {F12370} ** ** Definition: A <b>result table</b> is memory data structure created by the ** [sqlite3_get_table()] interface. A result table records the ** complete query results from one or more queries. ** ** The table conceptually has a number of rows and columns. But ** these numbers are not part of the result table itself. These ** numbers are obtained separately. Let N be the number of rows ** and M be the number of columns. ** ** A result table is an array of pointers to zero-terminated ** UTF-8 strings. There are (N+1)*M elements in the array. ** The first M pointers point to zero-terminated strings that ** contain the names of the columns. ** The remaining entries all point to query results. NULL ** values are give a NULL pointer. All other values are in ** their UTF-8 zero-terminated string representation as returned by ** [sqlite3_column_text()]. ** ** A result table might consists of one or more memory allocations. ** It is not safe to pass a result table directly to [sqlite3_free()]. ** A result table should be deallocated using [sqlite3_free_table()]. ** ** As an example of the result table format, suppose a query result ** is as follows: ** ** <blockquote><pre> ** Name | Age ** ----------------------- ** Alice | 43 ** Bob | 28 ** Cindy | 21 ** </pre></blockquote> ** ** There are two column (M==2) and three rows (N==3). Thus the ** result table has 8 entries. Suppose the result table is stored ** in an array names azResult. Then azResult holds this content: ** ** <blockquote><pre> ** azResult[0] = "Name"; ** azResult[1] = "Age"; ** azResult[2] = "Alice"; ** azResult[3] = "43"; ** azResult[4] = "Bob"; ** azResult[5] = "28"; ** azResult[6] = "Cindy"; ** azResult[7] = "21"; ** </pre></blockquote> ** ** The sqlite3_get_table() function evaluates one or more ** semicolon-separated SQL statements in the zero-terminated UTF-8 ** string of its 2nd parameter. It returns a result table to the ** pointer given in its 3rd parameter. ** ** After the calling function has finished using the result, it should ** pass the pointer to the result table to sqlite3_free_table() in order to ** release the memory that was malloc-ed. Because of the way the ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling ** function must not try to call [sqlite3_free()] directly. Only ** [sqlite3_free_table()] is able to release the memory properly and safely. ** ** The sqlite3_get_table() interface is implemented as a wrapper around ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access ** to any internal data structures of SQLite. It uses only the public ** interface defined here. As a consequence, errors that occur in the ** wrapper layer outside of the internal [sqlite3_exec()] call are not ** reflected in subsequent calls to [sqlite3_errcode()] or ** [sqlite3_errmsg()]. ** ** INVARIANTS: ** ** {F12371} If a [sqlite3_get_table()] fails a memory allocation, then ** it frees the result table under construction, aborts the ** query in process, skips any subsequent queries, sets the ** *resultp output pointer to NULL and returns [SQLITE_NOMEM]. ** ** {F12373} If the ncolumn parameter to [sqlite3_get_table()] is not NULL ** then [sqlite3_get_table()] write the number of columns in the ** result set of the query into *ncolumn if the query is ** successful (if the function returns SQLITE_OK). ** ** {F12374} If the nrow parameter to [sqlite3_get_table()] is not NULL ** then [sqlite3_get_table()] write the number of rows in the ** result set of the query into *nrow if the query is ** successful (if the function returns SQLITE_OK). ** ** {F12376} The [sqlite3_get_table()] function sets its *ncolumn value ** to the number of columns in the result set of the query in the ** sql parameter, or to zero if the query in sql has an empty ** result set. */ int sqlite3_get_table( sqlite3*, /* An open database */ const char *sql, /* SQL to be evaluated */ char ***pResult, /* Results of the query */ int *nrow, /* Number of result rows written here */ int *ncolumn, /* Number of result columns written here */ char **errmsg /* Error msg written here */ ); void sqlite3_free_table(char **result); /* ** CAPI3REF: Formatted String Printing Functions {F17400} ** ** These routines are workalikes of the "printf()" family of functions ** from the standard C library. ** ** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their ** results into memory obtained from [sqlite3_malloc()]. ** The strings returned by these two routines should be ** released by [sqlite3_free()]. Both routines return a ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough ** memory to hold the resulting string. ** ** In sqlite3_snprintf() routine is similar to "snprintf()" from ** the standard C library. The result is written into the ** buffer supplied as the second parameter whose size is given by ** the first parameter. Note that the order of the ** first two parameters is reversed from snprintf(). This is an ** historical accident that cannot be fixed without breaking ** backwards compatibility. Note also that sqlite3_snprintf() ** returns a pointer to its buffer instead of the number of ** characters actually written into the buffer. We admit that ** the number of characters written would be a more useful return ** value but we cannot change the implementation of sqlite3_snprintf() ** now without breaking compatibility. ** ** As long as the buffer size is greater than zero, sqlite3_snprintf() ** guarantees that the buffer is always zero-terminated. The first ** parameter "n" is the total size of the buffer, including space for ** the zero terminator. So the longest string that can be completely ** written will be n-1 characters. ** ** These routines all implement some additional formatting ** options that are useful for constructing SQL statements. ** All of the usual printf formatting options apply. In addition, there ** is are "%q", "%Q", and "%z" options. ** ** The %q option works like %s in that it substitutes a null-terminated ** string from the argument list. But %q also doubles every '\'' character. ** %q is designed for use inside a string literal. By doubling each '\'' ** character it escapes that character and allows it to be inserted into ** the string. ** ** For example, so some string variable contains text as follows: ** ** <blockquote><pre> ** char *zText = "It's a happy day!"; ** </pre></blockquote> ** ** One can use this text in an SQL statement as follows: ** ** <blockquote><pre> ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); ** sqlite3_exec(db, zSQL, 0, 0, 0); ** sqlite3_free(zSQL); ** </pre></blockquote> ** ** Because the %q format string is used, the '\'' character in zText ** is escaped and the SQL generated is as follows: ** ** <blockquote><pre> ** INSERT INTO table1 VALUES('It''s a happy day!') ** </pre></blockquote> ** ** This is correct. Had we used %s instead of %q, the generated SQL ** would have looked like this: ** ** <blockquote><pre> ** INSERT INTO table1 VALUES('It's a happy day!'); ** </pre></blockquote> ** ** This second example is an SQL syntax error. As a general rule you ** should always use %q instead of %s when inserting text into a string ** literal. ** ** The %Q option works like %q except it also adds single quotes around ** the outside of the total string. Or if the parameter in the argument ** list is a NULL pointer, %Q substitutes the text "NULL" (without single ** quotes) in place of the %Q option. {END} So, for example, one could say: ** ** <blockquote><pre> ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); ** sqlite3_exec(db, zSQL, 0, 0, 0); ** sqlite3_free(zSQL); ** </pre></blockquote> ** ** The code above will render a correct SQL statement in the zSQL ** variable even if the zText variable is a NULL pointer. ** ** The "%z" formatting option works exactly like "%s" with the ** addition that after the string has been read and copied into ** the result, [sqlite3_free()] is called on the input string. {END} ** ** INVARIANTS: ** ** {F17403} The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces ** return either pointers to zero-terminated UTF-8 strings held in ** memory obtained from [sqlite3_malloc()] or NULL pointers if ** a call to [sqlite3_malloc()] fails. ** ** {F17406} The [sqlite3_snprintf()] interface writes a zero-terminated ** UTF-8 string into the buffer pointed to by the second parameter ** provided that the first parameter is greater than zero. ** ** {F17407} The [sqlite3_snprintf()] interface does not writes slots of ** its output buffer (the second parameter) outside the range ** of 0 through N-1 (where N is the first parameter) ** regardless of the length of the string ** requested by the format specification. ** */ char *sqlite3_mprintf(const char*,...); char *sqlite3_vmprintf(const char*, va_list); char *sqlite3_snprintf(int,char*,const char*, ...); /* ** CAPI3REF: Memory Allocation Subsystem {F17300} ** ** The SQLite core uses these three routines for all of its own ** internal memory allocation needs. "Core" in the previous sentence ** does not include operating-system specific VFS implementation. The ** windows VFS uses native malloc and free for some operations. ** ** The sqlite3_malloc() routine returns a pointer to a block ** of memory at least N bytes in length, where N is the parameter. ** If sqlite3_malloc() is unable to obtain sufficient free ** memory, it returns a NULL pointer. If the parameter N to ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns ** a NULL pointer. ** ** Calling sqlite3_free() with a pointer previously returned ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so ** that it might be reused. The sqlite3_free() routine is ** a no-op if is called with a NULL pointer. Passing a NULL pointer ** to sqlite3_free() is harmless. After being freed, memory ** should neither be read nor written. Even reading previously freed ** memory might result in a segmentation fault or other severe error. ** Memory corruption, a segmentation fault, or other severe error ** might result if sqlite3_free() is called with a non-NULL pointer that ** was not obtained from sqlite3_malloc() or sqlite3_free(). ** ** The sqlite3_realloc() interface attempts to resize a ** prior memory allocation to be at least N bytes, where N is the ** second parameter. The memory allocation to be resized is the first ** parameter. If the first parameter to sqlite3_realloc() ** is a NULL pointer then its behavior is identical to calling ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc(). ** If the second parameter to sqlite3_realloc() is zero or ** negative then the behavior is exactly the same as calling ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc(). ** Sqlite3_realloc() returns a pointer to a memory allocation ** of at least N bytes in size or NULL if sufficient memory is unavailable. ** If M is the size of the prior allocation, then min(N,M) bytes ** of the prior allocation are copied into the beginning of buffer returned ** by sqlite3_realloc() and the prior allocation is freed. ** If sqlite3_realloc() returns NULL, then the prior allocation ** is not freed. ** ** The memory returned by sqlite3_malloc() and sqlite3_realloc() ** is always aligned to at least an 8 byte boundary. {END} ** ** The default implementation ** of the memory allocation subsystem uses the malloc(), realloc() ** and free() provided by the standard C library. {F17382} However, if ** SQLite is compiled with the following C preprocessor macro ** ** <blockquote> SQLITE_MEMORY_SIZE=<i>NNN</i> </blockquote> ** ** where <i>NNN</i> is an integer, then SQLite create a static ** array of at least <i>NNN</i> bytes in size and use that array ** for all of its dynamic memory allocation needs. {END} Additional ** memory allocator options may be added in future releases. ** ** In SQLite version 3.5.0 and 3.5.1, it was possible to define ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in ** implementation of these routines to be omitted. That capability ** is no longer provided. Only built-in memory allocators can be ** used. ** ** The windows OS interface layer calls ** the system malloc() and free() directly when converting ** filenames between the UTF-8 encoding used by SQLite ** and whatever filename encoding is used by the particular windows ** installation. Memory allocation errors are detected, but ** they are reported back as [SQLITE_CANTOPEN] or ** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. ** ** INVARIANTS: ** ** {F17303} The [sqlite3_malloc(N)] interface returns either a pointer to ** newly checked-out block of at least N bytes of memory ** that is 8-byte aligned, ** or it returns NULL if it is unable to fulfill the request. ** ** {F17304} The [sqlite3_malloc(N)] interface returns a NULL pointer if ** N is less than or equal to zero. ** ** {F17305} The [sqlite3_free(P)] interface releases memory previously ** returned from [sqlite3_malloc()] or [sqlite3_realloc()], ** making it available for reuse. ** ** {F17306} A call to [sqlite3_free(NULL)] is a harmless no-op. ** ** {F17310} A call to [sqlite3_realloc(0,N)] is equivalent to a call ** to [sqlite3_malloc(N)]. ** ** {F17312} A call to [sqlite3_realloc(P,0)] is equivalent to a call ** to [sqlite3_free(P)]. ** ** {F17315} The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()], ** and [sqlite3_free()] for all of its memory allocation and ** deallocation needs. ** ** {F17318} The [sqlite3_realloc(P,N)] interface returns either a pointer ** to a block of checked-out memory of at least N bytes in size ** that is 8-byte aligned, or a NULL pointer. ** ** {F17321} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first ** copies the first K bytes of content from P into the newly allocated ** where K is the lessor of N and the size of the buffer P. ** ** {F17322} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first ** releases the buffer P. ** ** {F17323} When [sqlite3_realloc(P,N)] returns NULL, the buffer P is ** not modified or released. ** ** LIMITATIONS: ** ** {U17350} The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] ** must be either NULL or else a pointer obtained from a prior ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that has ** not been released. ** ** {U17351} The application must not read or write any part of ** a block of memory after it has been released using ** [sqlite3_free()] or [sqlite3_realloc()]. ** */ void *sqlite3_malloc(int); void *sqlite3_realloc(void*, int); void sqlite3_free(void*); /* ** CAPI3REF: Memory Allocator Statistics {F17370} ** ** SQLite provides these two interfaces for reporting on the status ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] ** the memory allocation subsystem included within the SQLite. ** ** INVARIANTS: ** ** {F17371} The [sqlite3_memory_used()] routine returns the ** number of bytes of memory currently outstanding ** (malloced but not freed). ** ** {F17373} The [sqlite3_memory_highwater()] routine returns the maximum ** value of [sqlite3_memory_used()] ** since the highwater mark was last reset. ** ** {F17374} The values returned by [sqlite3_memory_used()] and ** [sqlite3_memory_highwater()] include any overhead ** added by SQLite in its implementation of [sqlite3_malloc()], ** but not overhead added by the any underlying system library ** routines that [sqlite3_malloc()] may call. ** ** {F17375} The memory highwater mark is reset to the current value of ** [sqlite3_memory_used()] if and only if the parameter to ** [sqlite3_memory_highwater()] is true. The value returned ** by [sqlite3_memory_highwater(1)] is the highwater mark ** prior to the reset. */ sqlite3_int64 sqlite3_memory_used(void); sqlite3_int64 sqlite3_memory_highwater(int resetFlag); /* ** CAPI3REF: Compile-Time Authorization Callbacks {F12500} ** ** This routine registers a authorizer callback with a particular ** database connection, supplied in the first argument. ** The authorizer callback is invoked as SQL statements are being compiled ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various ** points during the compilation process, as logic is being created ** to perform various actions, the authorizer callback is invoked to ** see if those actions are allowed. The authorizer callback should ** return SQLITE_OK to allow the action, [SQLITE_IGNORE] to disallow the ** specific action but allow the SQL statement to continue to be ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be ** rejected with an error. If the authorizer callback returns ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] ** then [sqlite3_prepare_v2()] or equivalent call that triggered ** the authorizer will fail with an error message. ** ** When the callback returns [SQLITE_OK], that means the operation ** requested is ok. When the callback returns [SQLITE_DENY], the ** [sqlite3_prepare_v2()] or equivalent call that triggered the ** authorizer will fail with an error message explaining that ** access is denied. If the authorizer code is [SQLITE_READ] ** and the callback returns [SQLITE_IGNORE] then the prepared ** statement is constructed to insert a NULL value in place of ** the table column that would have ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] ** return can be used to deny an untrusted user access to individual ** columns of a table. ** ** The first parameter to the authorizer callback is a copy of ** the third parameter to the sqlite3_set_authorizer() interface. ** The second parameter to the callback is an integer ** [SQLITE_COPY | action code] that specifies the particular action ** to be authorized. The third through sixth ** parameters to the callback are zero-terminated strings that contain ** additional details about the action to be authorized. ** ** An authorizer is used when preparing SQL statements from an untrusted ** source, to ensure that the SQL statements do not try to access data ** that they are not allowed to see, or that they do not try to ** execute malicious statements that damage the database. For ** example, an application may allow a user to enter arbitrary ** SQL queries for evaluation by a database. But the application does ** not want the user to be able to make arbitrary changes to the ** database. An authorizer could then be put in place while the ** user-entered SQL is being prepared that disallows everything ** except SELECT statements. ** ** Only a single authorizer can be in place on a database connection ** at a time. Each call to sqlite3_set_authorizer overrides the ** previous call. Disable the authorizer by installing a NULL callback. ** The authorizer is disabled by default. ** ** Note that the authorizer callback is invoked only during ** [sqlite3_prepare()] or its variants. Authorization is not ** performed during statement evaluation in [sqlite3_step()]. ** ** INVARIANTS: ** ** {F12501} The [sqlite3_set_authorizer(D,...)] interface registers a ** authorizer callback with database connection D. ** ** {F12502} The authorizer callback is invoked as SQL statements are ** being compiled ** ** {F12503} If the authorizer callback returns any value other than ** [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] then ** the [sqlite3_prepare_v2()] or equivalent call that caused ** the authorizer callback to run shall fail with an ** [SQLITE_ERROR] error code and an appropriate error message. ** ** {F12504} When the authorizer callback returns [SQLITE_OK], the operation ** described is coded normally. ** ** {F12505} When the authorizer callback returns [SQLITE_DENY], the ** [sqlite3_prepare_v2()] or equivalent call that caused the ** authorizer callback to run shall fail ** with an [SQLITE_ERROR] error code and an error message ** explaining that access is denied. ** ** {F12506} If the authorizer code (the 2nd parameter to the authorizer ** callback) is [SQLITE_READ] and the authorizer callback returns ** [SQLITE_IGNORE] then the prepared statement is constructed to ** insert a NULL value in place of the table column that would have ** been read if [SQLITE_OK] had been returned. ** ** {F12507} If the authorizer code (the 2nd parameter to the authorizer ** callback) is anything other than [SQLITE_READ], then ** a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY]. ** ** {F12510} The first parameter to the authorizer callback is a copy of ** the third parameter to the [sqlite3_set_authorizer()] interface. ** ** {F12511} The second parameter to the callback is an integer ** [SQLITE_COPY | action code] that specifies the particular action ** to be authorized. ** ** {F12512} The third through sixth parameters to the callback are ** zero-terminated strings that contain ** additional details about the action to be authorized. ** ** {F12520} Each call to [sqlite3_set_authorizer()] overrides the ** any previously installed authorizer. ** ** {F12521} A NULL authorizer means that no authorization ** callback is invoked. ** ** {F12522} The default authorizer is NULL. */ int sqlite3_set_authorizer( sqlite3*, int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), void *pUserData ); /* ** CAPI3REF: Authorizer Return Codes {F12590} ** ** The [sqlite3_set_authorizer | authorizer callback function] must ** return either [SQLITE_OK] or one of these two constants in order ** to signal SQLite whether or not the action is permitted. See the ** [sqlite3_set_authorizer | authorizer documentation] for additional ** information. */ #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ /* ** CAPI3REF: Authorizer Action Codes {F12550} ** ** The [sqlite3_set_authorizer()] interface registers a callback function ** that is invoked to authorizer certain SQL statement actions. The ** second parameter to the callback is an integer code that specifies ** what action is being authorized. These are the integer action codes that ** the authorizer callback may be passed. ** ** These action code values signify what kind of operation is to be ** authorized. The 3rd and 4th parameters to the authorization ** callback function will be parameters or NULL depending on which of these ** codes is used as the second parameter. The 5th parameter to the ** authorizer callback is the name of the database ("main", "temp", ** etc.) if applicable. The 6th parameter to the authorizer callback ** is the name of the inner-most trigger or view that is responsible for ** the access attempt or NULL if this access attempt is directly from ** top-level SQL code. ** ** INVARIANTS: ** ** {F12551} The second parameter to an ** [sqlite3_set_authorizer | authorizer callback is always an integer ** [SQLITE_COPY | authorizer code] that specifies what action ** is being authorized. ** ** {F12552} The 3rd and 4th parameters to the ** [sqlite3_set_authorizer | authorization callback function] ** will be parameters or NULL depending on which ** [SQLITE_COPY | authorizer code] is used as the second parameter. ** ** {F12553} The 5th parameter to the ** [sqlite3_set_authorizer | authorizer callback] is the name ** of the database (example: "main", "temp", etc.) if applicable. ** ** {F12554} The 6th parameter to the ** [sqlite3_set_authorizer | authorizer callback] is the name ** of the inner-most trigger or view that is responsible for ** the access attempt or NULL if this access attempt is directly from ** top-level SQL code. */ /******************************************* 3rd ************ 4th ***********/ #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ #define SQLITE_DELETE 9 /* Table Name NULL */ #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ #define SQLITE_DROP_VIEW 17 /* View Name NULL */ #define SQLITE_INSERT 18 /* Table Name NULL */ #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ #define SQLITE_READ 20 /* Table Name Column Name */ #define SQLITE_SELECT 21 /* NULL NULL */ #define SQLITE_TRANSACTION 22 /* NULL NULL */ #define SQLITE_UPDATE 23 /* Table Name Column Name */ #define SQLITE_ATTACH 24 /* Filename NULL */ #define SQLITE_DETACH 25 /* Database Name NULL */ #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ #define SQLITE_REINDEX 27 /* Index Name NULL */ #define SQLITE_ANALYZE 28 /* Table Name NULL */ #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ #define SQLITE_FUNCTION 31 /* Function Name NULL */ #define SQLITE_COPY 0 /* No longer used */ /* ** CAPI3REF: Tracing And Profiling Functions {F12280} ** ** These routines register callback functions that can be used for ** tracing and profiling the execution of SQL statements. ** ** The callback function registered by sqlite3_trace() is invoked at ** various times when an SQL statement is being run by [sqlite3_step()]. ** The callback returns a UTF-8 rendering of the SQL statement text ** as the statement first begins executing. Additional callbacks occur ** as each triggersubprogram is entered. The callbacks for triggers ** contain a UTF-8 SQL comment that identifies the trigger. ** ** The callback function registered by sqlite3_profile() is invoked ** as each SQL statement finishes. The profile callback contains ** the original statement text and an estimate of wall-clock time ** of how long that statement took to run. ** ** The sqlite3_profile() API is currently considered experimental and ** is subject to change or removal in a future release. ** ** The trigger reporting feature of the trace callback is considered ** experimental and is subject to change or removal in future releases. ** Future versions of SQLite might also add new trace callback ** invocations. ** ** INVARIANTS: ** ** {F12281} The callback function registered by [sqlite3_trace()] is ** whenever an SQL statement first begins to execute and ** whenever a trigger subprogram first begins to run. ** ** {F12282} Each call to [sqlite3_trace()] overrides the previously ** registered trace callback. ** ** {F12283} A NULL trace callback disables tracing. ** ** {F12284} The first argument to the trace callback is a copy of ** the pointer which was the 3rd argument to [sqlite3_trace()]. ** ** {F12285} The second argument to the trace callback is a ** zero-terminated UTF8 string containing the original text ** of the SQL statement as it was passed into [sqlite3_prepare_v2()] ** or the equivalent, or an SQL comment indicating the beginning ** of a trigger subprogram. ** ** {F12287} The callback function registered by [sqlite3_profile()] is invoked ** as each SQL statement finishes. ** ** {F12288} The first parameter to the profile callback is a copy of ** the 3rd parameter to [sqlite3_profile()]. ** ** {F12289} The second parameter to the profile callback is a ** zero-terminated UTF-8 string that contains the complete text of ** the SQL statement as it was processed by [sqlite3_prepare_v2()] ** or the equivalent. ** ** {F12290} The third parameter to the profile callback is an estimate ** of the number of nanoseconds of wall-clock time required to ** run the SQL statement from start to finish. */ void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*); void *sqlite3_profile(sqlite3*, void(*xProfile)(void*,const char*,sqlite3_uint64), void*); /* ** CAPI3REF: Query Progress Callbacks {F12910} ** ** This routine configures a callback function - the ** progress callback - that is invoked periodically during long ** running calls to [sqlite3_exec()], [sqlite3_step()] and ** [sqlite3_get_table()]. An example use for this ** interface is to keep a GUI updated during a large query. ** ** If the progress callback returns non-zero, the opertion is ** interrupted. This feature can be used to implement a ** "Cancel" button on a GUI dialog box. ** ** INVARIANTS: ** ** {F12911} The callback function registered by [sqlite3_progress_handler()] ** is invoked periodically during long running calls to ** [sqlite3_step()]. ** ** {F12912} The progress callback is invoked once for every N virtual ** machine opcodes, where N is the second argument to ** the [sqlite3_progress_handler()] call that registered ** the callback. <todo>What if N is less than 1?</todo> ** ** {F12913} The progress callback itself is identified by the third ** argument to [sqlite3_progress_handler()]. ** ** {F12914} The fourth argument [sqlite3_progress_handler()] is a *** void pointer passed to the progress callback ** function each time it is invoked. ** ** {F12915} If a call to [sqlite3_step()] results in fewer than ** N opcodes being executed, ** then the progress callback is never invoked. {END} ** ** {F12916} Every call to [sqlite3_progress_handler()] ** overwrites any previously registere progress handler. ** ** {F12917} If the progress handler callback is NULL then no progress ** handler is invoked. ** ** {F12918} If the progress callback returns a result other than 0, then ** the behavior is a if [sqlite3_interrupt()] had been called. */ void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); /* ** CAPI3REF: Opening A New Database Connection {F12700} ** ** These routines open an SQLite database file whose name ** is given by the filename argument. ** The filename argument is interpreted as UTF-8 ** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16 ** in the native byte order for [sqlite3_open16()]. ** An [sqlite3*] handle is usually returned in *ppDb, even ** if an error occurs. The only exception is if SQLite is unable ** to allocate memory to hold the [sqlite3] object, a NULL will ** be written into *ppDb instead of a pointer to the [sqlite3] object. ** If the database is opened (and/or created) ** successfully, then [SQLITE_OK] is returned. Otherwise an ** error code is returned. The ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain ** an English language description of the error. ** ** The default encoding for the database will be UTF-8 if ** [sqlite3_open()] or [sqlite3_open_v2()] is called and ** UTF-16 in the native byte order if [sqlite3_open16()] is used. ** ** Whether or not an error occurs when it is opened, resources ** associated with the [sqlite3*] handle should be released by passing it ** to [sqlite3_close()] when it is no longer required. ** ** The [sqlite3_open_v2()] interface works like [sqlite3_open()] ** except that it acccepts two additional parameters for additional control ** over the new database connection. The flags parameter can be ** one of: ** ** <ol> ** <li> [SQLITE_OPEN_READONLY] ** <li> [SQLITE_OPEN_READWRITE] ** <li> [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE] ** </ol> ** ** The first value opens the database read-only. ** If the database does not previously exist, an error is returned. ** The second option opens ** the database for reading and writing if possible, or reading only if ** if the file is write protected. In either case the database ** must already exist or an error is returned. The third option ** opens the database for reading and writing and creates it if it does ** not already exist. ** The third options is behavior that is always used for [sqlite3_open()] ** and [sqlite3_open16()]. ** ** If the filename is ":memory:", then an private ** in-memory database is created for the connection. This in-memory ** database will vanish when the database connection is closed. Future ** version of SQLite might make use of additional special filenames ** that begin with the ":" character. It is recommended that ** when a database filename really does begin with ** ":" that you prefix the filename with a pathname like "./" to ** avoid ambiguity. ** ** If the filename is an empty string, then a private temporary ** on-disk database will be created. This private database will be ** automatically deleted as soon as the database connection is closed. ** ** The fourth parameter to sqlite3_open_v2() is the name of the ** [sqlite3_vfs] object that defines the operating system ** interface that the new database connection should use. If the ** fourth parameter is a NULL pointer then the default [sqlite3_vfs] ** object is used. ** ** <b>Note to windows users:</b> The encoding used for the filename argument ** of [sqlite3_open()] and [sqlite3_open_v2()] must be UTF-8, not whatever ** codepage is currently defined. Filenames containing international ** characters must be converted to UTF-8 prior to passing them into ** [sqlite3_open()] or [sqlite3_open_v2()]. ** ** INVARIANTS: ** ** {F12701} The [sqlite3_open()], [sqlite3_open16()], and ** [sqlite3_open_v2()] interfaces create a new ** [database connection] associated with ** the database file given in their first parameter. ** ** {F12702} The filename argument is interpreted as UTF-8 ** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16 ** in the native byte order for [sqlite3_open16()]. ** ** {F12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()], ** or [sqlite3_open_v2()] writes a pointer to a new ** [database connection] into *ppDb. ** ** {F12704} The [sqlite3_open()], [sqlite3_open16()], and ** [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success, ** or an appropriate [error code] on failure. ** ** {F12706} The default text encoding for a new database created using ** [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8. ** ** {F12707} The default text encoding for a new database created using ** [sqlite3_open16()] will be UTF-16. ** ** {F12709} The [sqlite3_open(F,D)] interface is equivalent to ** [sqlite3_open_v2(F,D,G,0)] where the G parameter is ** [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE]. ** ** {F12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the ** bit value [SQLITE_OPEN_READONLY] then the database is opened ** for reading only. ** ** {F12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the ** bit value [SQLITE_OPEN_READWRITE] then the database is opened ** reading and writing if possible, or for reading only if the ** file is write protected by the operating system. ** ** {F12713} If the G parameter to [sqlite3_open(v2(F,D,G,V)] omits the ** bit value [SQLITE_OPEN_CREATE] and the database does not ** previously exist, an error is returned. ** ** {F12714} If the G parameter to [sqlite3_open(v2(F,D,G,V)] contains the ** bit value [SQLITE_OPEN_CREATE] and the database does not ** previously exist, then an attempt is made to create and ** initialize the database. ** ** {F12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()], ** or [sqlite3_open_v2()] is ":memory:", then an private, ** ephemeral, in-memory database is created for the connection. ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required ** in sqlite3_open_v2()?</todo> ** ** {F12719} If the filename is NULL or an empty string, then a private, ** ephermeral on-disk database will be created. ** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required ** in sqlite3_open_v2()?</todo> ** ** {F12721} The [database connection] created by ** [sqlite3_open_v2(F,D,G,V)] will use the ** [sqlite3_vfs] object identified by the V parameter, or ** the default [sqlite3_vfs] object is V is a NULL pointer. */ int sqlite3_open( const char *filename, /* Database filename (UTF-8) */ sqlite3 **ppDb /* OUT: SQLite db handle */ ); int sqlite3_open16( const void *filename, /* Database filename (UTF-16) */ sqlite3 **ppDb /* OUT: SQLite db handle */ ); int sqlite3_open_v2( const char *filename, /* Database filename (UTF-8) */ sqlite3 **ppDb, /* OUT: SQLite db handle */ int flags, /* Flags */ const char *zVfs /* Name of VFS module to use */ ); /* ** CAPI3REF: Error Codes And Messages {F12800} ** ** The sqlite3_errcode() interface returns the numeric ** [SQLITE_OK | result code] or [SQLITE_IOERR_READ | extended result code] ** for the most recent failed sqlite3_* API call associated ** with [sqlite3] handle 'db'. If a prior API call failed but the ** most recent API call succeeded, the return value from sqlite3_errcode() ** is undefined. ** ** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language ** text that describes the error, as either UTF8 or UTF16 respectively. ** Memory to hold the error message string is managed internally. ** The application does not need to worry with freeing the result. ** However, the error string might be overwritten or deallocated by ** subsequent calls to other SQLite interface functions. ** ** INVARIANTS: ** ** {F12801} The [sqlite3_errcode(D)] interface returns the numeric ** [SQLITE_OK | result code] or ** [SQLITE_IOERR_READ | extended result code] ** for the most recently failed interface call associated ** with [database connection] D. ** ** {F12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)] ** interfaces return English-language text that describes ** the error in the mostly recently failed interface call, ** encoded as either UTF8 or UTF16 respectively. ** ** {F12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()] ** are valid until the next SQLite interface call. ** ** {F12808} Calls to API routines that do not return an error code ** (example: [sqlite3_data_count()]) do not ** change the error code or message returned by ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()]. ** ** {F12809} Interfaces that are not associated with a specific ** [database connection] (examples: ** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()] ** do not change the values returned by ** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()]. */ int sqlite3_errcode(sqlite3 *db); const char *sqlite3_errmsg(sqlite3*); const void *sqlite3_errmsg16(sqlite3*); /* ** CAPI3REF: SQL Statement Object {F13000} ** KEYWORDS: {prepared statement} {prepared statements} ** ** An instance of this object represent single SQL statements. This ** object is variously known as a "prepared statement" or a ** "compiled SQL statement" or simply as a "statement". ** ** The life of a statement object goes something like this: ** ** <ol> ** <li> Create the object using [sqlite3_prepare_v2()] or a related ** function. ** <li> Bind values to host parameters using ** [sqlite3_bind_blob | sqlite3_bind_* interfaces]. ** <li> Run the SQL by calling [sqlite3_step()] one or more times. ** <li> Reset the statement using [sqlite3_reset()] then go back ** to step 2. Do this zero or more times. ** <li> Destroy the object using [sqlite3_finalize()]. ** </ol> ** ** Refer to documentation on individual methods above for additional ** information. */ typedef struct sqlite3_stmt sqlite3_stmt; /* ** CAPI3REF: Compiling An SQL Statement {F13010} ** ** To execute an SQL query, it must first be compiled into a byte-code ** program using one of these routines. ** ** The first argument "db" is an [database connection] ** obtained from a prior call to [sqlite3_open()], [sqlite3_open_v2()] ** or [sqlite3_open16()]. ** The second argument "zSql" is the statement to be compiled, encoded ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() ** interfaces uses UTF-8 and sqlite3_prepare16() and sqlite3_prepare16_v2() ** use UTF-16. {END} ** ** If the nByte argument is less ** than zero, then zSql is read up to the first zero terminator. ** If nByte is non-negative, then it is the maximum number of ** bytes read from zSql. When nByte is non-negative, the ** zSql string ends at either the first '\000' or '\u0000' character or ** until the nByte-th byte, whichever comes first. {END} ** ** *pzTail is made to point to the first byte past the end of the ** first SQL statement in zSql. These routines only compiles the first ** statement in zSql, so *pzTail is left pointing to what remains ** uncompiled. ** ** *ppStmt is left pointing to a compiled [prepared statement] that can be ** executed using [sqlite3_step()]. Or if there is an error, *ppStmt is ** set to NULL. If the input text contains no SQL (if the input ** is and empty string or a comment) then *ppStmt is set to NULL. ** {U13018} The calling procedure is responsible for deleting the ** compiled SQL statement ** using [sqlite3_finalize()] after it has finished with it. ** ** On success, [SQLITE_OK] is returned. Otherwise an ** [error code] is returned. ** ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are ** recommended for all new programs. The two older interfaces are retained ** for backwards compatibility, but their use is discouraged. ** In the "v2" interfaces, the prepared statement ** that is returned (the [sqlite3_stmt] object) contains a copy of the ** original SQL text. {END} This causes the [sqlite3_step()] interface to ** behave a differently in two ways: ** ** <ol> ** <li> ** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it ** always used to do, [sqlite3_step()] will automatically recompile the SQL ** statement and try to run it again. If the schema has changed in ** a way that makes the statement no longer valid, [sqlite3_step()] will still ** return [SQLITE_SCHEMA]. But unlike the legacy behavior, ** [SQLITE_SCHEMA] is now a fatal error. Calling ** [sqlite3_prepare_v2()] again will not make the ** error go away. Note: use [sqlite3_errmsg()] to find the text ** of the parsing error that results in an [SQLITE_SCHEMA] return. {END} ** </li> ** ** <li> ** When an error occurs, ** [sqlite3_step()] will return one of the detailed ** [error codes] or [extended error codes]. ** The legacy behavior was that [sqlite3_step()] would only return a generic ** [SQLITE_ERROR] result code and you would have to make a second call to ** [sqlite3_reset()] in order to find the underlying cause of the problem. ** With the "v2" prepare interfaces, the underlying reason for the error is ** returned immediately. ** </li> ** </ol> ** ** INVARIANTS: ** ** {F13011} The [sqlite3_prepare(db,zSql,...)] and ** [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the ** text in their zSql parameter as UTF-8. ** ** {F13012} The [sqlite3_prepare16(db,zSql,...)] and ** [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the ** text in their zSql parameter as UTF-16 in the native byte order. ** ** {F13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)] ** and its variants is less than zero, then SQL text is ** read from zSql is read up to the first zero terminator. ** ** {F13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)] ** and its variants is non-negative, then nBytes bytes ** SQL text is read from zSql. ** ** {F13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants ** if the zSql input text contains more than one SQL statement ** and pzTail is not NULL, then *pzTail is made to point to the ** first byte past the end of the first SQL statement in zSql. ** <todo>What does *pzTail point to if there is one statement?</todo> ** ** {F13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)] ** or one of its variants writes into *ppStmt a pointer to a new ** [prepared statement] or a pointer to NULL ** if zSql contains nothing other than whitespace or comments. ** ** {F13019} The [sqlite3_prepare_v2()] interface and its variants return ** [SQLITE_OK] or an appropriate [error code] upon failure. ** ** {F13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its ** variants returns an error (any value other than [SQLITE_OK]) ** it first sets *ppStmt to NULL. */ int sqlite3_prepare( sqlite3 *db, /* Database handle */ const char *zSql, /* SQL statement, UTF-8 encoded */ int nByte, /* Maximum length of zSql in bytes. */ sqlite3_stmt **ppStmt, /* OUT: Statement handle */ const char **pzTail /* OUT: Pointer to unused portion of zSql */ ); int sqlite3_prepare_v2( sqlite3 *db, /* Database handle */ const char *zSql, /* SQL statement, UTF-8 encoded */ int nByte, /* Maximum length of zSql in bytes. */ sqlite3_stmt **ppStmt, /* OUT: Statement handle */ const char **pzTail /* OUT: Pointer to unused portion of zSql */ ); int sqlite3_prepare16( sqlite3 *db, /* Database handle */ const void *zSql, /* SQL statement, UTF-16 encoded */ int nByte, /* Maximum length of zSql in bytes. */ sqlite3_stmt **ppStmt, /* OUT: Statement handle */ const void **pzTail /* OUT: Pointer to unused portion of zSql */ ); int sqlite3_prepare16_v2( sqlite3 *db, /* Database handle */ const void *zSql, /* SQL statement, UTF-16 encoded */ int nByte, /* Maximum length of zSql in bytes. */ sqlite3_stmt **ppStmt, /* OUT: Statement handle */ const void **pzTail /* OUT: Pointer to unused portion of zSql */ ); /* ** CAPIREF: Retrieving Statement SQL {F13100} ** ** This intereface can be used to retrieve a saved copy of the original ** SQL text used to create a [prepared statement]. ** ** INVARIANTS: ** ** {F13101} If the [prepared statement] passed as ** the an argument to [sqlite3_sql()] was compiled ** compiled using either [sqlite3_prepare_v2()] or ** [sqlite3_prepare16_v2()], ** then [sqlite3_sql()] function returns a pointer to a ** zero-terminated string containing a UTF-8 rendering ** of the original SQL statement. ** ** {F13102} If the [prepared statement] passed as ** the an argument to [sqlite3_sql()] was compiled ** compiled using either [sqlite3_prepare()] or ** [sqlite3_prepare16()], ** then [sqlite3_sql()] function returns a NULL pointer. ** ** {F13103} The string returned by [sqlite3_sql(S)] is valid until the ** [prepared statement] S is deleted using [sqlite3_finalize(S)]. */ const char *sqlite3_sql(sqlite3_stmt *pStmt); /* ** CAPI3REF: Dynamically Typed Value Object {F15000} ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} ** ** SQLite uses the sqlite3_value object to represent all values ** that can be stored in a database table. ** SQLite uses dynamic typing for the values it stores. ** Values stored in sqlite3_value objects can be ** be integers, floating point values, strings, BLOBs, or NULL. ** ** An sqlite3_value object may be either "protected" or "unprotected". ** Some interfaces require a protected sqlite3_value. Other interfaces ** will accept either a protected or an unprotected sqlite3_value. ** Every interface that accepts sqlite3_value arguments specifies ** whether or not it requires a protected sqlite3_value. ** ** The terms "protected" and "unprotected" refer to whether or not ** a mutex is held. A internal mutex is held for a protected ** sqlite3_value object but no mutex is held for an unprotected ** sqlite3_value object. If SQLite is compiled to be single-threaded ** (with SQLITE_THREADSAFE=0 and with [sqlite3_threadsafe()] returning 0) ** then there is no distinction between ** protected and unprotected sqlite3_value objects and they can be ** used interchangable. However, for maximum code portability it ** is recommended that applications make the distinction between ** between protected and unprotected sqlite3_value objects even if ** they are single threaded. ** ** The sqlite3_value objects that are passed as parameters into the ** implementation of application-defined SQL functions are protected. ** The sqlite3_value object returned by ** [sqlite3_column_value()] is unprotected. ** Unprotected sqlite3_value objects may only be used with ** [sqlite3_result_value()] and [sqlite3_bind_value()]. All other ** interfaces that use sqlite3_value require protected sqlite3_value objects. */ typedef struct Mem sqlite3_value; /* ** CAPI3REF: SQL Function Context Object {F16001} ** ** The context in which an SQL function executes is stored in an ** sqlite3_context object. A pointer to an sqlite3_context ** object is always first parameter to application-defined SQL functions. */ typedef struct sqlite3_context sqlite3_context; /* ** CAPI3REF: Binding Values To Prepared Statements {F13500} ** ** In the SQL strings input to [sqlite3_prepare_v2()] and its ** variants, literals may be replace by a parameter in one ** of these forms: ** ** <ul> ** <li> ? ** <li> ?NNN ** <li> :VVV ** <li> @VVV ** <li> $VVV ** </ul> ** ** In the parameter forms shown above NNN is an integer literal, ** VVV alpha-numeric parameter name. ** The values of these parameters (also called "host parameter names" ** or "SQL parameters") ** can be set using the sqlite3_bind_*() routines defined here. ** ** The first argument to the sqlite3_bind_*() routines always ** is a pointer to the [sqlite3_stmt] object returned from ** [sqlite3_prepare_v2()] or its variants. The second ** argument is the index of the parameter to be set. The ** first parameter has an index of 1. When the same named ** parameter is used more than once, second and subsequent ** occurrences have the same index as the first occurrence. ** The index for named parameters can be looked up using the ** [sqlite3_bind_parameter_name()] API if desired. The index ** for "?NNN" parameters is the value of NNN. ** The NNN value must be between 1 and the compile-time ** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999). ** ** The third argument is the value to bind to the parameter. ** ** In those ** routines that have a fourth argument, its value is the number of bytes ** in the parameter. To be clear: the value is the number of <u>bytes</u> ** in the value, not the number of characters. The number ** of bytes does not include the zero-terminator at the end of strings. ** If the fourth parameter is negative, the length of the string is ** number of bytes up to the first zero terminator. ** ** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or ** string after SQLite has finished with it. If the fifth argument is ** the special value [SQLITE_STATIC], then SQLite assumes that the ** information is in static, unmanaged space and does not need to be freed. ** If the fifth argument has the value [SQLITE_TRANSIENT], then ** SQLite makes its own private copy of the data immediately, before ** the sqlite3_bind_*() routine returns. ** ** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that ** is filled with zeros. A zeroblob uses a fixed amount of memory ** (just an integer to hold it size) while it is being processed. ** Zeroblobs are intended to serve as place-holders for BLOBs whose ** content is later written using ** [sqlite3_blob_open | increment BLOB I/O] routines. A negative ** value for the zeroblob results in a zero-length BLOB. ** ** The sqlite3_bind_*() routines must be called after ** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and ** before [sqlite3_step()]. ** Bindings are not cleared by the [sqlite3_reset()] routine. ** Unbound parameters are interpreted as NULL. ** ** These routines return [SQLITE_OK] on success or an error code if ** anything goes wrong. [SQLITE_RANGE] is returned if the parameter ** index is out of range. [SQLITE_NOMEM] is returned if malloc fails. ** [SQLITE_MISUSE] might be returned if these routines are called on a ** virtual machine that is the wrong state or which has already been finalized. ** Detection of misuse is unreliable. Applications should not depend ** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a ** a logic error in the application. Future versions of SQLite might ** panic rather than return SQLITE_MISUSE. ** ** See also: [sqlite3_bind_parameter_count()], ** [sqlite3_bind_parameter_name()], and ** [sqlite3_bind_parameter_index()]. ** ** INVARIANTS: ** ** {F13506} The [sqlite3_prepare | SQL statement compiler] recognizes ** tokens of the forms "?", "?NNN", "$VVV", ":VVV", and "@VVV" ** as SQL parameters, where NNN is any sequence of one or more ** digits and where VVV is any sequence of one or more ** alphanumeric characters or "::" optionally followed by ** a string containing no spaces and contained within parentheses. ** ** {F13509} The initial value of an SQL parameter is NULL. ** ** {F13512} The index of an "?" SQL parameter is one larger than the ** largest index of SQL parameter to the left, or 1 if ** the "?" is the leftmost SQL parameter. ** ** {F13515} The index of an "?NNN" SQL parameter is the integer NNN. ** ** {F13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is ** the same as the index of leftmost occurances of the same ** parameter, or one more than the largest index over all ** parameters to the left if this is the first occurrance ** of this parameter, or 1 if this is the leftmost parameter. ** ** {F13521} The [sqlite3_prepare | SQL statement compiler] fail with ** an [SQLITE_RANGE] error if the index of an SQL parameter ** is less than 1 or greater than SQLITE_MAX_VARIABLE_NUMBER. ** ** {F13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)] ** associate the value V with all SQL parameters having an ** index of N in the [prepared statement] S. ** ** {F13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)] ** override prior calls with the same values of S and N. ** ** {F13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)] ** persist across calls to [sqlite3_reset(S)]. ** ** {F13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)], ** [sqlite3_bind_text(S,N,V,L,D)], or ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L ** bytes of the blob or string pointed to by V, when L ** is non-negative. ** ** {F13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or ** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters ** from V through the first zero character when L is negative. ** ** {F13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)], ** [sqlite3_bind_text(S,N,V,L,D)], or ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special ** constant [SQLITE_STATIC], SQLite assumes that the value V ** is held in static unmanaged space that will not change ** during the lifetime of the binding. ** ** {F13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)], ** [sqlite3_bind_text(S,N,V,L,D)], or ** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special ** constant [SQLITE_TRANSIENT], the routine makes a ** private copy of V value before it returns. ** ** {F13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)], ** [sqlite3_bind_text(S,N,V,L,D)], or ** [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to ** a function, SQLite invokes that function to destroy the ** V value after it has finished using the V value. ** ** {F13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound ** is a blob of L bytes, or a zero-length blob if L is negative. ** ** {F13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may ** be either a [protected sqlite3_value] object or an ** [unprotected sqlite3_value] object. */ int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); int sqlite3_bind_double(sqlite3_stmt*, int, double); int sqlite3_bind_int(sqlite3_stmt*, int, int); int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); int sqlite3_bind_null(sqlite3_stmt*, int); int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*)); int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); /* ** CAPI3REF: Number Of SQL Parameters {F13600} ** ** This routine can be used to find the number of SQL parameters ** in a prepared statement. SQL parameters are tokens of the ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as ** place-holders for values that are [sqlite3_bind_blob | bound] ** to the parameters at a later time. ** ** This routine actually returns the index of the largest parameter. ** For all forms except ?NNN, this will correspond to the number of ** unique parameters. If parameters of the ?NNN are used, there may ** be gaps in the list. ** ** See also: [sqlite3_bind_blob|sqlite3_bind()], ** [sqlite3_bind_parameter_name()], and ** [sqlite3_bind_parameter_index()]. ** ** INVARIANTS: ** ** {F13601} The [sqlite3_bind_parameter_count(S)] interface returns ** the largest index of all SQL parameters in the ** [prepared statement] S, or 0 if S ** contains no SQL parameters. */ int sqlite3_bind_parameter_count(sqlite3_stmt*); /* ** CAPI3REF: Name Of A Host Parameter {F13620} ** ** This routine returns a pointer to the name of the n-th ** SQL parameter in a [prepared statement]. ** SQL parameters of the form ":AAA" or "@AAA" or "$AAA" have a name ** which is the string ":AAA" or "@AAA" or "$VVV". ** In other words, the initial ":" or "$" or "@" ** is included as part of the name. ** Parameters of the form "?" or "?NNN" have no name. ** ** The first host parameter has an index of 1, not 0. ** ** If the value n is out of range or if the n-th parameter is ** nameless, then NULL is returned. The returned string is ** always in the UTF-8 encoding even if the named parameter was ** originally specified as UTF-16 in [sqlite3_prepare16()] or ** [sqlite3_prepare16_v2()]. ** ** See also: [sqlite3_bind_blob|sqlite3_bind()], ** [sqlite3_bind_parameter_count()], and ** [sqlite3_bind_parameter_index()]. ** ** INVARIANTS: ** ** {F13621} The [sqlite3_bind_parameter_name(S,N)] interface returns ** a UTF-8 rendering of the name of the SQL parameter in ** [prepared statement] S having index N, or ** NULL if there is no SQL parameter with index N or if the ** parameter with index N is an anonymous parameter "?" or ** a numbered parameter "?NNN". */ const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); /* ** CAPI3REF: Index Of A Parameter With A Given Name {F13640} ** ** Return the index of an SQL parameter given its name. The ** index value returned is suitable for use as the second ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero ** is returned if no matching parameter is found. The parameter ** name must be given in UTF-8 even if the original statement ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. ** ** See also: [sqlite3_bind_blob|sqlite3_bind()], ** [sqlite3_bind_parameter_count()], and ** [sqlite3_bind_parameter_index()]. ** ** INVARIANTS: ** ** {F13641} The [sqlite3_bind_parameter_index(S,N)] interface returns ** the index of SQL parameter in [prepared statement] ** S whose name matches the UTF-8 string N, or 0 if there is ** no match. */ int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); /* ** CAPI3REF: Reset All Bindings On A Prepared Statement {F13660} ** ** Contrary to the intuition of many, [sqlite3_reset()] does not ** reset the [sqlite3_bind_blob | bindings] on a ** [prepared statement]. Use this routine to ** reset all host parameters to NULL. ** ** INVARIANTS: ** ** {F13661} The [sqlite3_clear_bindings(S)] interface resets all ** SQL parameter bindings in [prepared statement] S ** back to NULL. */ int sqlite3_clear_bindings(sqlite3_stmt*); /* ** CAPI3REF: Number Of Columns In A Result Set {F13710} ** ** Return the number of columns in the result set returned by the ** [prepared statement]. This routine returns 0 ** if pStmt is an SQL statement that does not return data (for ** example an UPDATE). ** ** INVARIANTS: ** ** {F13711} The [sqlite3_column_count(S)] interface returns the number of ** columns in the result set generated by the ** [prepared statement] S, or 0 if S does not generate ** a result set. */ int sqlite3_column_count(sqlite3_stmt *pStmt); /* ** CAPI3REF: Column Names In A Result Set {F13720} ** ** These routines return the name assigned to a particular column ** in the result set of a SELECT statement. The sqlite3_column_name() ** interface returns a pointer to a zero-terminated UTF8 string ** and sqlite3_column_name16() returns a pointer to a zero-terminated ** UTF16 string. The first parameter is the ** [prepared statement] that implements the SELECT statement. ** The second parameter is the column number. The left-most column is ** number 0. ** ** The returned string pointer is valid until either the ** [prepared statement] is destroyed by [sqlite3_finalize()] ** or until the next call sqlite3_column_name() or sqlite3_column_name16() ** on the same column. ** ** If sqlite3_malloc() fails during the processing of either routine ** (for example during a conversion from UTF-8 to UTF-16) then a ** NULL pointer is returned. ** ** The name of a result column is the value of the "AS" clause for ** that column, if there is an AS clause. If there is no AS clause ** then the name of the column is unspecified and may change from ** one release of SQLite to the next. ** ** INVARIANTS: ** ** {F13721} A successful invocation of the [sqlite3_column_name(S,N)] ** interface returns the name ** of the Nth column (where 0 is the left-most column) for the ** result set of [prepared statement] S as a ** zero-terminated UTF-8 string. ** ** {F13723} A successful invocation of the [sqlite3_column_name16(S,N)] ** interface returns the name ** of the Nth column (where 0 is the left-most column) for the ** result set of [prepared statement] S as a ** zero-terminated UTF-16 string in the native byte order. ** ** {F13724} The [sqlite3_column_name()] and [sqlite3_column_name16()] ** interfaces return a NULL pointer if they are unable to ** allocate memory memory to hold there normal return strings. ** ** {F13725} If the N parameter to [sqlite3_column_name(S,N)] or ** [sqlite3_column_name16(S,N)] is out of range, then the ** interfaces returns a NULL pointer. ** ** {F13726} The strings returned by [sqlite3_column_name(S,N)] and ** [sqlite3_column_name16(S,N)] are valid until the next ** call to either routine with the same S and N parameters ** or until [sqlite3_finalize(S)] is called. ** ** {F13727} When a result column of a [SELECT] statement contains ** an AS clause, the name of that column is the indentifier ** to the right of the AS keyword. */ const char *sqlite3_column_name(sqlite3_stmt*, int N); const void *sqlite3_column_name16(sqlite3_stmt*, int N); /* ** CAPI3REF: Source Of Data In A Query Result {F13740} ** ** These routines provide a means to determine what column of what ** table in which database a result of a SELECT statement comes from. ** The name of the database or table or column can be returned as ** either a UTF8 or UTF16 string. The _database_ routines return ** the database name, the _table_ routines return the table name, and ** the origin_ routines return the column name. ** The returned string is valid until ** the [prepared statement] is destroyed using ** [sqlite3_finalize()] or until the same information is requested ** again in a different encoding. ** ** The names returned are the original un-aliased names of the ** database, table, and column. ** ** The first argument to the following calls is a [prepared statement]. ** These functions return information about the Nth column returned by ** the statement, where N is the second function argument. ** ** If the Nth column returned by the statement is an expression ** or subquery and is not a column value, then all of these functions ** return NULL. These routine might also return NULL if a memory ** allocation error occurs. Otherwise, they return the ** name of the attached database, table and column that query result ** column was extracted from. ** ** As with all other SQLite APIs, those postfixed with "16" return ** UTF-16 encoded strings, the other functions return UTF-8. {END} ** ** These APIs are only available if the library was compiled with the ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined. ** ** {U13751} ** If two or more threads call one or more of these routines against the same ** prepared statement and column at the same time then the results are ** undefined. ** ** INVARIANTS: ** ** {F13741} The [sqlite3_column_database_name(S,N)] interface returns either ** the UTF-8 zero-terminated name of the database from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13742} The [sqlite3_column_database_name16(S,N)] interface returns either ** the UTF-16 native byte order ** zero-terminated name of the database from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13743} The [sqlite3_column_table_name(S,N)] interface returns either ** the UTF-8 zero-terminated name of the table from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13744} The [sqlite3_column_table_name16(S,N)] interface returns either ** the UTF-16 native byte order ** zero-terminated name of the table from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13745} The [sqlite3_column_origin_name(S,N)] interface returns either ** the UTF-8 zero-terminated name of the table column from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13746} The [sqlite3_column_origin_name16(S,N)] interface returns either ** the UTF-16 native byte order ** zero-terminated name of the table column from which the ** Nth result column of [prepared statement] S ** is extracted, or NULL if the the Nth column of S is a ** general expression or if unable to allocate memory ** to store the name. ** ** {F13748} The return values from ** [sqlite3_column_database_name|column metadata interfaces] ** are valid ** for the lifetime of the [prepared statement] ** or until the encoding is changed by another metadata ** interface call for the same prepared statement and column. ** ** LIMITATIONS: ** ** {U13751} If two or more threads call one or more ** [sqlite3_column_database_name|column metadata interfaces] ** the same [prepared statement] and result column ** at the same time then the results are undefined. */ const char *sqlite3_column_database_name(sqlite3_stmt*,int); const void *sqlite3_column_database_name16(sqlite3_stmt*,int); const char *sqlite3_column_table_name(sqlite3_stmt*,int); const void *sqlite3_column_table_name16(sqlite3_stmt*,int); const char *sqlite3_column_origin_name(sqlite3_stmt*,int); const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); /* ** CAPI3REF: Declared Datatype Of A Query Result {F13760} ** ** The first parameter is a [prepared statement]. ** If this statement is a SELECT statement and the Nth column of the ** returned result set of that SELECT is a table column (not an ** expression or subquery) then the declared type of the table ** column is returned. If the Nth column of the result set is an ** expression or subquery, then a NULL pointer is returned. ** The returned string is always UTF-8 encoded. {END} ** For example, in the database schema: ** ** CREATE TABLE t1(c1 VARIANT); ** ** And the following statement compiled: ** ** SELECT c1 + 1, c1 FROM t1; ** ** Then this routine would return the string "VARIANT" for the second ** result column (i==1), and a NULL pointer for the first result column ** (i==0). ** ** SQLite uses dynamic run-time typing. So just because a column ** is declared to contain a particular type does not mean that the ** data stored in that column is of the declared type. SQLite is ** strongly typed, but the typing is dynamic not static. Type ** is associated with individual values, not with the containers ** used to hold those values. ** ** INVARIANTS: ** ** {F13761} A successful call to [sqlite3_column_decltype(S,N)] ** returns a zero-terminated UTF-8 string containing the ** the declared datatype of the table column that appears ** as the Nth column (numbered from 0) of the result set to the ** [prepared statement] S. ** ** {F13762} A successful call to [sqlite3_column_decltype16(S,N)] ** returns a zero-terminated UTF-16 native byte order string ** containing the declared datatype of the table column that appears ** as the Nth column (numbered from 0) of the result set to the ** [prepared statement] S. ** ** {F13763} If N is less than 0 or N is greater than or equal to ** the number of columns in [prepared statement] S ** or if the Nth column of S is an expression or subquery rather ** than a table column or if a memory allocation failure ** occurs during encoding conversions, then ** calls to [sqlite3_column_decltype(S,N)] or ** [sqlite3_column_decltype16(S,N)] return NULL. */ const char *sqlite3_column_decltype(sqlite3_stmt*,int); const void *sqlite3_column_decltype16(sqlite3_stmt*,int); /* ** CAPI3REF: Evaluate An SQL Statement {F13200} ** ** After an [prepared statement] has been prepared with a call ** to either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or to one of ** the legacy interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], ** then this function must be called one or more times to evaluate the ** statement. ** ** The details of the behavior of this sqlite3_step() interface depend ** on whether the statement was prepared using the newer "v2" interface ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the ** new "v2" interface is recommended for new applications but the legacy ** interface will continue to be supported. ** ** In the lagacy interface, the return value will be either [SQLITE_BUSY], ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. ** With the "v2" interface, any of the other [SQLITE_OK | result code] ** or [SQLITE_IOERR_READ | extended result code] might be returned as ** well. ** ** [SQLITE_BUSY] means that the database engine was unable to acquire the ** database locks it needs to do its job. If the statement is a COMMIT ** or occurs outside of an explicit transaction, then you can retry the ** statement. If the statement is not a COMMIT and occurs within a ** explicit transaction then you should rollback the transaction before ** continuing. ** ** [SQLITE_DONE] means that the statement has finished executing ** successfully. sqlite3_step() should not be called again on this virtual ** machine without first calling [sqlite3_reset()] to reset the virtual ** machine back to its initial state. ** ** If the SQL statement being executed returns any data, then ** [SQLITE_ROW] is returned each time a new row of data is ready ** for processing by the caller. The values may be accessed using ** the [sqlite3_column_int | column access functions]. ** sqlite3_step() is called again to retrieve the next row of data. ** ** [SQLITE_ERROR] means that a run-time error (such as a constraint ** violation) has occurred. sqlite3_step() should not be called again on ** the VM. More information may be found by calling [sqlite3_errmsg()]. ** With the legacy interface, a more specific error code (example: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) ** can be obtained by calling [sqlite3_reset()] on the ** [prepared statement]. In the "v2" interface, ** the more specific error code is returned directly by sqlite3_step(). ** ** [SQLITE_MISUSE] means that the this routine was called inappropriately. ** Perhaps it was called on a [prepared statement] that has ** already been [sqlite3_finalize | finalized] or on one that had ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could ** be the case that the same database connection is being used by two or ** more threads at the same moment in time. ** ** <b>Goofy Interface Alert:</b> ** In the legacy interface, ** the sqlite3_step() API always returns a generic error code, ** [SQLITE_ERROR], following any error other than [SQLITE_BUSY] ** and [SQLITE_MISUSE]. You must call [sqlite3_reset()] or ** [sqlite3_finalize()] in order to find one of the specific ** [error codes] that better describes the error. ** We admit that this is a goofy design. The problem has been fixed ** with the "v2" interface. If you prepare all of your SQL statements ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()], then the ** more specific [error codes] are returned directly ** by sqlite3_step(). The use of the "v2" interface is recommended. ** ** INVARIANTS: ** ** {F13202} If [prepared statement] S is ready to be ** run, then [sqlite3_step(S)] advances that prepared statement ** until to completion or until it is ready to return another ** row of the result set or an interrupt or run-time error occurs. ** ** {F15304} When a call to [sqlite3_step(S)] causes the ** [prepared statement] S to run to completion, ** the function returns [SQLITE_DONE]. ** ** {F15306} When a call to [sqlite3_step(S)] stops because it is ready ** to return another row of the result set, it returns ** [SQLITE_ROW]. ** ** {F15308} If a call to [sqlite3_step(S)] encounters an ** [sqlite3_interrupt|interrupt] or a run-time error, ** it returns an appropraite error code that is not one of ** [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE]. ** ** {F15310} If an [sqlite3_interrupt|interrupt] or run-time error ** occurs during a call to [sqlite3_step(S)] ** for a [prepared statement] S created using ** legacy interfaces [sqlite3_prepare()] or ** [sqlite3_prepare16()] then the function returns either ** [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE]. */ int sqlite3_step(sqlite3_stmt*); /* ** CAPI3REF: Number of columns in a result set {F13770} ** ** Return the number of values in the current row of the result set. ** ** INVARIANTS: ** ** {F13771} After a call to [sqlite3_step(S)] that returns ** [SQLITE_ROW], the [sqlite3_data_count(S)] routine ** will return the same value as the ** [sqlite3_column_count(S)] function. ** ** {F13772} After [sqlite3_step(S)] has returned any value other than ** [SQLITE_ROW] or before [sqlite3_step(S)] has been ** called on the [prepared statement] for ** the first time since it was [sqlite3_prepare|prepared] ** or [sqlite3_reset|reset], the [sqlite3_data_count(S)] ** routine returns zero. */ int sqlite3_data_count(sqlite3_stmt *pStmt); /* ** CAPI3REF: Fundamental Datatypes {F10265} ** KEYWORDS: SQLITE_TEXT ** ** {F10266}Every value in SQLite has one of five fundamental datatypes: ** ** <ul> ** <li> 64-bit signed integer ** <li> 64-bit IEEE floating point number ** <li> string ** <li> BLOB ** <li> NULL ** </ul> {END} ** ** These constants are codes for each of those types. ** ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 ** for a completely different meaning. Software that links against both ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT not ** SQLITE_TEXT. */ #define SQLITE_INTEGER 1 #define SQLITE_FLOAT 2 #define SQLITE_BLOB 4 #define SQLITE_NULL 5 #ifdef SQLITE_TEXT # undef SQLITE_TEXT #else # define SQLITE_TEXT 3 #endif #define SQLITE3_TEXT 3 /* ** CAPI3REF: Results Values From A Query {F13800} ** ** These routines form the "result set query" interface. ** ** These routines return information about ** a single column of the current result row of a query. In every ** case the first argument is a pointer to the ** [prepared statement] that is being ** evaluated (the [sqlite3_stmt*] that was returned from ** [sqlite3_prepare_v2()] or one of its variants) and ** the second argument is the index of the column for which information ** should be returned. The left-most column of the result set ** has an index of 0. ** ** If the SQL statement is not currently point to a valid row, or if the ** the column index is out of range, the result is undefined. ** These routines may only be called when the most recent call to ** [sqlite3_step()] has returned [SQLITE_ROW] and neither ** [sqlite3_reset()] nor [sqlite3_finalize()] has been call subsequently. ** If any of these routines are called after [sqlite3_reset()] or ** [sqlite3_finalize()] or after [sqlite3_step()] has returned ** something other than [SQLITE_ROW], the results are undefined. ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] ** are called from a different thread while any of these routines ** are pending, then the results are undefined. ** ** The sqlite3_column_type() routine returns ** [SQLITE_INTEGER | datatype code] for the initial data type ** of the result column. The returned value is one of [SQLITE_INTEGER], ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value ** returned by sqlite3_column_type() is only meaningful if no type ** conversions have occurred as described below. After a type conversion, ** the value returned by sqlite3_column_type() is undefined. Future ** versions of SQLite may change the behavior of sqlite3_column_type() ** following a type conversion. ** ** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() ** routine returns the number of bytes in that BLOB or string. ** If the result is a UTF-16 string, then sqlite3_column_bytes() converts ** the string to UTF-8 and then returns the number of bytes. ** If the result is a numeric value then sqlite3_column_bytes() uses ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns ** the number of bytes in that string. ** The value returned does not include the zero terminator at the end ** of the string. For clarity: the value returned is the number of ** bytes in the string, not the number of characters. ** ** Strings returned by sqlite3_column_text() and sqlite3_column_text16(), ** even empty strings, are always zero terminated. The return ** value from sqlite3_column_blob() for a zero-length blob is an arbitrary ** pointer, possibly even a NULL pointer. ** ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes() ** but leaves the result in UTF-16 in native byte order instead of UTF-8. ** The zero terminator is not included in this count. ** ** The object returned by [sqlite3_column_value()] is an ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()]. ** If the [unprotected sqlite3_value] object returned by ** [sqlite3_column_value()] is used in any other way, including calls ** to routines like ** [sqlite3_value_int()], [sqlite3_value_text()], or [sqlite3_value_bytes()], ** then the behavior is undefined. ** ** These routines attempt to convert the value where appropriate. For ** example, if the internal representation is FLOAT and a text result ** is requested, [sqlite3_snprintf()] is used internally to do the conversion ** automatically. The following table details the conversions that ** are applied: ** ** <blockquote> ** <table border="1"> ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion ** ** <tr><td> NULL <td> INTEGER <td> Result is 0 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer ** <tr><td> INTEGER <td> BLOB <td> Same as for INTEGER->TEXT ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT ** <tr><td> TEXT <td> INTEGER <td> Use atoi() ** <tr><td> TEXT <td> FLOAT <td> Use atof() ** <tr><td> TEXT <td> BLOB <td> No change ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi() ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof() ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed ** </table> ** </blockquote> ** ** The table above makes reference to standard C library functions atoi() ** and atof(). SQLite does not really use these functions. It has its ** on equavalent internal routines. The atoi() and atof() names are ** used in the table for brevity and because they are familiar to most ** C programmers. ** ** Note that when type conversions occur, pointers returned by prior ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or ** sqlite3_column_text16() may be invalidated. ** Type conversions and pointer invalidations might occur ** in the following cases: ** ** <ul> ** <li><p> The initial content is a BLOB and sqlite3_column_text() ** or sqlite3_column_text16() is called. A zero-terminator might ** need to be added to the string.</p></li> ** ** <li><p> The initial content is UTF-8 text and sqlite3_column_bytes16() or ** sqlite3_column_text16() is called. The content must be converted ** to UTF-16.</p></li> ** ** <li><p> The initial content is UTF-16 text and sqlite3_column_bytes() or ** sqlite3_column_text() is called. The content must be converted ** to UTF-8.</p></li> ** </ul> ** ** Conversions between UTF-16be and UTF-16le are always done in place and do ** not invalidate a prior pointer, though of course the content of the buffer ** that the prior pointer points to will have been modified. Other kinds ** of conversion are done in place when it is possible, but sometime it is ** not possible and in those cases prior pointers are invalidated. ** ** The safest and easiest to remember policy is to invoke these routines ** in one of the following ways: ** ** <ul> ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> ** </ul> ** ** In other words, you should call sqlite3_column_text(), sqlite3_column_blob(), ** or sqlite3_column_text16() first to force the result into the desired ** format, then invoke sqlite3_column_bytes() or sqlite3_column_bytes16() to ** find the size of the result. Do not mix call to sqlite3_column_text() or ** sqlite3_column_blob() with calls to sqlite3_column_bytes16(). And do not ** mix calls to sqlite3_column_text16() with calls to sqlite3_column_bytes(). ** ** The pointers returned are valid until a type conversion occurs as ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or ** [sqlite3_finalize()] is called. The memory space used to hold strings ** and blobs is freed automatically. Do <b>not</b> pass the pointers returned ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into ** [sqlite3_free()]. ** ** If a memory allocation error occurs during the evaluation of any ** of these routines, a default value is returned. The default value ** is either the integer 0, the floating point number 0.0, or a NULL ** pointer. Subsequent calls to [sqlite3_errcode()] will return ** [SQLITE_NOMEM]. ** ** INVARIANTS: ** ** {F13803} The [sqlite3_column_blob(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a blob and then returns a ** pointer to the converted value. ** ** {F13806} The [sqlite3_column_bytes(S,N)] interface returns the ** number of bytes in the blob or string (exclusive of the ** zero terminator on the string) that was returned by the ** most recent call to [sqlite3_column_blob(S,N)] or ** [sqlite3_column_text(S,N)]. ** ** {F13809} The [sqlite3_column_bytes16(S,N)] interface returns the ** number of bytes in the string (exclusive of the ** zero terminator on the string) that was returned by the ** most recent call to [sqlite3_column_text16(S,N)]. ** ** {F13812} The [sqlite3_column_double(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a floating point value and ** returns a copy of that value. ** ** {F13815} The [sqlite3_column_int(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a 64-bit signed integer and ** returns the lower 32 bits of that integer. ** ** {F13818} The [sqlite3_column_int64(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a 64-bit signed integer and ** returns a copy of that integer. ** ** {F13821} The [sqlite3_column_text(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a zero-terminated UTF-8 ** string and returns a pointer to that string. ** ** {F13824} The [sqlite3_column_text16(S,N)] interface converts the ** Nth column in the current row of the result set for ** [prepared statement] S into a zero-terminated 2-byte ** aligned UTF-16 native byte order ** string and returns a pointer to that string. ** ** {F13827} The [sqlite3_column_type(S,N)] interface returns ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT], ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for ** the Nth column in the current row of the result set for ** [prepared statement] S. ** ** {F13830} The [sqlite3_column_value(S,N)] interface returns a ** pointer to an [unprotected sqlite3_value] object for the ** Nth column in the current row of the result set for ** [prepared statement] S. */ const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); int sqlite3_column_bytes(sqlite3_stmt*, int iCol); int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); double sqlite3_column_double(sqlite3_stmt*, int iCol); int sqlite3_column_int(sqlite3_stmt*, int iCol); sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); int sqlite3_column_type(sqlite3_stmt*, int iCol); sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); /* ** CAPI3REF: Destroy A Prepared Statement Object {F13300} ** ** The sqlite3_finalize() function is called to delete a ** [prepared statement]. If the statement was ** executed successfully, or not executed at all, then SQLITE_OK is returned. ** If execution of the statement failed then an ** [error code] or [extended error code] ** is returned. ** ** This routine can be called at any point during the execution of the ** [prepared statement]. If the virtual machine has not ** completed execution when this routine is called, that is like ** encountering an error or an interrupt. (See [sqlite3_interrupt()].) ** Incomplete updates may be rolled back and transactions cancelled, ** depending on the circumstances, and the ** [error code] returned will be [SQLITE_ABORT]. ** ** INVARIANTS: ** ** {F11302} The [sqlite3_finalize(S)] interface destroys the ** [prepared statement] S and releases all ** memory and file resources held by that object. ** ** {F11304} If the most recent call to [sqlite3_step(S)] for the ** [prepared statement] S returned an error, ** then [sqlite3_finalize(S)] returns that same error. */ int sqlite3_finalize(sqlite3_stmt *pStmt); /* ** CAPI3REF: Reset A Prepared Statement Object {F13330} ** ** The sqlite3_reset() function is called to reset a ** [prepared statement] object. ** back to its initial state, ready to be re-executed. ** Any SQL statement variables that had values bound to them using ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. ** Use [sqlite3_clear_bindings()] to reset the bindings. ** ** {F11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S ** back to the beginning of its program. ** ** {F11334} If the most recent call to [sqlite3_step(S)] for ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], ** or if [sqlite3_step(S)] has never before been called on S, ** then [sqlite3_reset(S)] returns [SQLITE_OK]. ** ** {F11336} If the most recent call to [sqlite3_step(S)] for ** [prepared statement] S indicated an error, then ** [sqlite3_reset(S)] returns an appropriate [error code]. ** ** {F11338} The [sqlite3_reset(S)] interface does not change the values ** of any [sqlite3_bind_blob|bindings] on [prepared statement] S. */ int sqlite3_reset(sqlite3_stmt *pStmt); /* ** CAPI3REF: Create Or Redefine SQL Functions {F16100} ** KEYWORDS: {function creation routines} ** ** These two functions (collectively known as ** "function creation routines") are used to add SQL functions or aggregates ** or to redefine the behavior of existing SQL functions or aggregates. The ** difference only between the two is that the second parameter, the ** name of the (scalar) function or aggregate, is encoded in UTF-8 for ** sqlite3_create_function() and UTF-16 for sqlite3_create_function16(). ** ** The first parameter is the [database connection] to which the SQL ** function is to be added. If a single ** program uses more than one [database connection] internally, then SQL ** functions must be added individually to each [database connection]. ** ** The second parameter is the name of the SQL function to be created ** or redefined. ** The length of the name is limited to 255 bytes, exclusive of the ** zero-terminator. Note that the name length limit is in bytes, not ** characters. Any attempt to create a function with a longer name ** will result in an SQLITE_ERROR error. ** ** The third parameter is the number of arguments that the SQL function or ** aggregate takes. If this parameter is negative, then the SQL function or ** aggregate may take any number of arguments. ** ** The fourth parameter, eTextRep, specifies what ** [SQLITE_UTF8 | text encoding] this SQL function prefers for ** its parameters. Any SQL function implementation should be able to work ** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be ** more efficient with one encoding than another. It is allowed to ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple ** times with the same function but with different values of eTextRep. ** When multiple implementations of the same function are available, SQLite ** will pick the one that involves the least amount of data conversion. ** If there is only a single implementation which does not care what ** text encoding is used, then the fourth argument should be ** [SQLITE_ANY]. ** ** The fifth parameter is an arbitrary pointer. The implementation ** of the function can gain access to this pointer using ** [sqlite3_user_data()]. ** ** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are ** pointers to C-language functions that implement the SQL ** function or aggregate. A scalar SQL function requires an implementation of ** the xFunc callback only, NULL pointers should be passed as the xStep ** and xFinal parameters. An aggregate SQL function requires an implementation ** of xStep and xFinal and NULL should be passed for xFunc. To delete an ** existing SQL function or aggregate, pass NULL for all three function ** callback. ** ** It is permitted to register multiple implementations of the same ** functions with the same name but with either differing numbers of ** arguments or differing perferred text encodings. SQLite will use ** the implementation most closely matches the way in which the ** SQL function is used. ** ** INVARIANTS: ** ** {F16103} The [sqlite3_create_function16()] interface behaves exactly ** like [sqlite3_create_function()] in every way except that it ** interprets the zFunctionName argument as ** zero-terminated UTF-16 native byte order instead of as a ** zero-terminated UTF-8. ** ** {F16106} A successful invocation of ** the [sqlite3_create_function(D,X,N,E,...)] interface registers ** or replaces callback functions in [database connection] D ** used to implement the SQL function named X with N parameters ** and having a perferred text encoding of E. ** ** {F16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)] ** replaces the P, F, S, and L values from any prior calls with ** the same D, X, N, and E values. ** ** {F16112} The [sqlite3_create_function(D,X,...)] interface fails with ** a return code of [SQLITE_ERROR] if the SQL function name X is ** longer than 255 bytes exclusive of the zero terminator. ** ** {F16118} Either F must be NULL and S and L are non-NULL or else F ** is non-NULL and S and L are NULL, otherwise ** [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR]. ** ** {F16121} The [sqlite3_create_function(D,...)] interface fails with an ** error code of [SQLITE_BUSY] if there exist [prepared statements] ** associated with the [database connection] D. ** ** {F16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an ** error code of [SQLITE_ERROR] if parameter N (specifying the number ** of arguments to the SQL function being registered) is less ** than -1 or greater than 127. ** ** {F16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)] ** interface causes callbacks to be invoked for the SQL function ** named X when the number of arguments to the SQL function is ** exactly N. ** ** {F16130} When N is -1, the [sqlite3_create_function(D,X,N,...)] ** interface causes callbacks to be invoked for the SQL function ** named X with any number of arguments. ** ** {F16133} When calls to [sqlite3_create_function(D,X,N,...)] ** specify multiple implementations of the same function X ** and when one implementation has N>=0 and the other has N=(-1) ** the implementation with a non-zero N is preferred. ** ** {F16136} When calls to [sqlite3_create_function(D,X,N,E,...)] ** specify multiple implementations of the same function X with ** the same number of arguments N but with different ** encodings E, then the implementation where E matches the ** database encoding is preferred. ** ** {F16139} For an aggregate SQL function created using ** [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finializer ** function L will always be invoked exactly once if the ** step function S is called one or more times. ** ** {F16142} When SQLite invokes either the xFunc or xStep function of ** an application-defined SQL function or aggregate created ** by [sqlite3_create_function()] or [sqlite3_create_function16()], ** then the array of [sqlite3_value] objects passed as the ** third parameter are always [protected sqlite3_value] objects. */ int sqlite3_create_function( sqlite3 *db, const char *zFunctionName, int nArg, int eTextRep, void *pApp, void (*xFunc)(sqlite3_context*,int,sqlite3_value**), void (*xStep)(sqlite3_context*,int,sqlite3_value**), void (*xFinal)(sqlite3_context*) ); int sqlite3_create_function16( sqlite3 *db, const void *zFunctionName, int nArg, int eTextRep, void *pApp, void (*xFunc)(sqlite3_context*,int,sqlite3_value**), void (*xStep)(sqlite3_context*,int,sqlite3_value**), void (*xFinal)(sqlite3_context*) ); /* ** CAPI3REF: Text Encodings {F10267} ** ** These constant define integer codes that represent the various ** text encodings supported by SQLite. */ #define SQLITE_UTF8 1 #define SQLITE_UTF16LE 2 #define SQLITE_UTF16BE 3 #define SQLITE_UTF16 4 /* Use native byte order */ #define SQLITE_ANY 5 /* sqlite3_create_function only */ #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ /* ** CAPI3REF: Obsolete Functions ** ** These functions are all now obsolete. In order to maintain ** backwards compatibility with older code, we continue to support ** these functions. However, new development projects should avoid ** the use of these functions. To help encourage people to avoid ** using these functions, we are not going to tell you want they do. */ int sqlite3_aggregate_count(sqlite3_context*); int sqlite3_expired(sqlite3_stmt*); int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); int sqlite3_global_recover(void); void sqlite3_thread_cleanup(void); int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64); /* ** CAPI3REF: Obtaining SQL Function Parameter Values {F15100} ** ** The C-language implementation of SQL functions and aggregates uses ** this set of interface routines to access the parameter values on ** the function or aggregate. ** ** The xFunc (for scalar functions) or xStep (for aggregates) parameters ** to [sqlite3_create_function()] and [sqlite3_create_function16()] ** define callbacks that implement the SQL functions and aggregates. ** The 4th parameter to these callbacks is an array of pointers to ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for ** each parameter to the SQL function. These routines are used to ** extract values from the [sqlite3_value] objects. ** ** These routines work only with [protected sqlite3_value] objects. ** Any attempt to use these routines on an [unprotected sqlite3_value] ** object results in undefined behavior. ** ** These routines work just like the corresponding ** [sqlite3_column_blob | sqlite3_column_* routines] except that ** these routines take a single [protected sqlite3_value] object pointer ** instead of an [sqlite3_stmt*] pointer and an integer column number. ** ** The sqlite3_value_text16() interface extracts a UTF16 string ** in the native byte-order of the host machine. The ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces ** extract UTF16 strings as big-endian and little-endian respectively. ** ** The sqlite3_value_numeric_type() interface attempts to apply ** numeric affinity to the value. This means that an attempt is ** made to convert the value to an integer or floating point. If ** such a conversion is possible without loss of information (in other ** words if the value is a string that looks like a number) ** then the conversion is done. Otherwise no conversion occurs. The ** [SQLITE_INTEGER | datatype] after conversion is returned. ** ** Please pay particular attention to the fact that the pointer that ** is returned from [sqlite3_value_blob()], [sqlite3_value_text()], or ** [sqlite3_value_text16()] can be invalidated by a subsequent call to ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], ** or [sqlite3_value_text16()]. ** ** These routines must be called from the same thread as ** the SQL function that supplied the [sqlite3_value*] parameters. ** ** ** INVARIANTS: ** ** {F15103} The [sqlite3_value_blob(V)] interface converts the ** [protected sqlite3_value] object V into a blob and then returns a ** pointer to the converted value. ** ** {F15106} The [sqlite3_value_bytes(V)] interface returns the ** number of bytes in the blob or string (exclusive of the ** zero terminator on the string) that was returned by the ** most recent call to [sqlite3_value_blob(V)] or ** [sqlite3_value_text(V)]. ** ** {F15109} The [sqlite3_value_bytes16(V)] interface returns the ** number of bytes in the string (exclusive of the ** zero terminator on the string) that was returned by the ** most recent call to [sqlite3_value_text16(V)], ** [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)]. ** ** {F15112} The [sqlite3_value_double(V)] interface converts the ** [protected sqlite3_value] object V into a floating point value and ** returns a copy of that value. ** ** {F15115} The [sqlite3_value_int(V)] interface converts the ** [protected sqlite3_value] object V into a 64-bit signed integer and ** returns the lower 32 bits of that integer. ** ** {F15118} The [sqlite3_value_int64(V)] interface converts the ** [protected sqlite3_value] object V into a 64-bit signed integer and ** returns a copy of that integer. ** ** {F15121} The [sqlite3_value_text(V)] interface converts the ** [protected sqlite3_value] object V into a zero-terminated UTF-8 ** string and returns a pointer to that string. ** ** {F15124} The [sqlite3_value_text16(V)] interface converts the ** [protected sqlite3_value] object V into a zero-terminated 2-byte ** aligned UTF-16 native byte order ** string and returns a pointer to that string. ** ** {F15127} The [sqlite3_value_text16be(V)] interface converts the ** [protected sqlite3_value] object V into a zero-terminated 2-byte ** aligned UTF-16 big-endian ** string and returns a pointer to that string. ** ** {F15130} The [sqlite3_value_text16le(V)] interface converts the ** [protected sqlite3_value] object V into a zero-terminated 2-byte ** aligned UTF-16 little-endian ** string and returns a pointer to that string. ** ** {F15133} The [sqlite3_value_type(V)] interface returns ** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT], ** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for ** the [sqlite3_value] object V. ** ** {F15136} The [sqlite3_value_numeric_type(V)] interface converts ** the [protected sqlite3_value] object V into either an integer or ** a floating point value if it can do so without loss of ** information, and returns one of [SQLITE_NULL], ** [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or ** [SQLITE_BLOB] as appropriate for ** the [protected sqlite3_value] object V after the conversion attempt. */ const void *sqlite3_value_blob(sqlite3_value*); int sqlite3_value_bytes(sqlite3_value*); int sqlite3_value_bytes16(sqlite3_value*); double sqlite3_value_double(sqlite3_value*); int sqlite3_value_int(sqlite3_value*); sqlite3_int64 sqlite3_value_int64(sqlite3_value*); const unsigned char *sqlite3_value_text(sqlite3_value*); const void *sqlite3_value_text16(sqlite3_value*); const void *sqlite3_value_text16le(sqlite3_value*); const void *sqlite3_value_text16be(sqlite3_value*); int sqlite3_value_type(sqlite3_value*); int sqlite3_value_numeric_type(sqlite3_value*); /* ** CAPI3REF: Obtain Aggregate Function Context {F16210} ** ** The implementation of aggregate SQL functions use this routine to allocate ** a structure for storing their state. ** The first time the sqlite3_aggregate_context() routine is ** is called for a particular aggregate, SQLite allocates nBytes of memory ** zeros that memory, and returns a pointer to it. ** On second and subsequent calls to sqlite3_aggregate_context() ** for the same aggregate function index, the same buffer is returned. ** The implementation ** of the aggregate can use the returned buffer to accumulate data. ** ** SQLite automatically frees the allocated buffer when the aggregate ** query concludes. ** ** The first parameter should be a copy of the ** [sqlite3_context | SQL function context] that is the first ** parameter to the callback routine that implements the aggregate ** function. ** ** This routine must be called from the same thread in which ** the aggregate SQL function is running. ** ** INVARIANTS: ** ** {F16211} The first invocation of [sqlite3_aggregate_context(C,N)] for ** a particular instance of an aggregate function (for a particular ** context C) causes SQLite to allocation N bytes of memory, ** zero that memory, and return a pointer to the allocationed ** memory. ** ** {F16213} If a memory allocation error occurs during ** [sqlite3_aggregate_context(C,N)] then the function returns 0. ** ** {F16215} Second and subsequent invocations of ** [sqlite3_aggregate_context(C,N)] for the same context pointer C ** ignore the N parameter and return a pointer to the same ** block of memory returned by the first invocation. ** ** {F16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is ** automatically freed on the next call to [sqlite3_reset()] ** or [sqlite3_finalize()] for the [prepared statement] containing ** the aggregate function associated with context C. */ void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); /* ** CAPI3REF: User Data For Functions {F16240} ** ** The sqlite3_user_data() interface returns a copy of ** the pointer that was the pUserData parameter (the 5th parameter) ** of the the [sqlite3_create_function()] ** and [sqlite3_create_function16()] routines that originally ** registered the application defined function. {END} ** ** This routine must be called from the same thread in which ** the application-defined function is running. ** ** INVARIANTS: ** ** {F16243} The [sqlite3_user_data(C)] interface returns a copy of the ** P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)] ** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that ** registered the SQL function associated with ** [sqlite3_context] C. */ void *sqlite3_user_data(sqlite3_context*); /* ** CAPI3REF: Function Auxiliary Data {F16270} ** ** The following two functions may be used by scalar SQL functions to ** associate meta-data with argument values. If the same value is passed to ** multiple invocations of the same SQL function during query execution, under ** some circumstances the associated meta-data may be preserved. This may ** be used, for example, to add a regular-expression matching scalar ** function. The compiled version of the regular expression is stored as ** meta-data associated with the SQL value passed as the regular expression ** pattern. The compiled regular expression can be reused on multiple ** invocations of the same function so that the original pattern string ** does not need to be recompiled on each invocation. ** ** The sqlite3_get_auxdata() interface returns a pointer to the meta-data ** associated by the sqlite3_set_auxdata() function with the Nth argument ** value to the application-defined function. ** If no meta-data has been ever been set for the Nth ** argument of the function, or if the cooresponding function parameter ** has changed since the meta-data was set, then sqlite3_get_auxdata() ** returns a NULL pointer. ** ** The sqlite3_set_auxdata() interface saves the meta-data ** pointed to by its 3rd parameter as the meta-data for the N-th ** argument of the application-defined function. Subsequent ** calls to sqlite3_get_auxdata() might return this data, if it has ** not been destroyed. ** If it is not NULL, SQLite will invoke the destructor ** function given by the 4th parameter to sqlite3_set_auxdata() on ** the meta-data when the corresponding function parameter changes ** or when the SQL statement completes, whichever comes first. ** ** SQLite is free to call the destructor and drop meta-data on ** any parameter of any function at any time. The only guarantee ** is that the destructor will be called before the metadata is ** dropped. ** ** In practice, meta-data is preserved between function calls for ** expressions that are constant at compile time. This includes literal ** values and SQL variables. ** ** These routines must be called from the same thread in which ** the SQL function is running. ** ** INVARIANTS: ** ** {F16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer ** to metadata associated with the Nth parameter of the SQL function ** whose context is C, or NULL if there is no metadata associated ** with that parameter. ** ** {F16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata ** pointer P to the Nth parameter of the SQL function with context ** C. ** ** {F16276} SQLite will invoke the destructor D with a single argument ** which is the metadata pointer P following a call to ** [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold ** the metadata. ** ** {F16277} SQLite ceases to hold metadata for an SQL function parameter ** when the value of that parameter changes. ** ** {F16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor ** is called for any prior metadata associated with the same function ** context C and parameter N. ** ** {F16279} SQLite will call destructors for any metadata it is holding ** in a particular [prepared statement] S when either ** [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called. */ void *sqlite3_get_auxdata(sqlite3_context*, int N); void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); /* ** CAPI3REF: Constants Defining Special Destructor Behavior {F10280} ** ** These are special value for the destructor that is passed in as the ** final argument to routines like [sqlite3_result_blob()]. If the destructor ** argument is SQLITE_STATIC, it means that the content pointer is constant ** and will never change. It does not need to be destroyed. The ** SQLITE_TRANSIENT value means that the content will likely change in ** the near future and that SQLite should make its own private copy of ** the content before returning. ** ** The typedef is necessary to work around problems in certain ** C++ compilers. See ticket #2191. */ typedef void (*sqlite3_destructor_type)(void*); #define SQLITE_STATIC ((sqlite3_destructor_type)0) #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) /* ** CAPI3REF: Setting The Result Of An SQL Function {F16400} ** ** These routines are used by the xFunc or xFinal callbacks that ** implement SQL functions and aggregates. See ** [sqlite3_create_function()] and [sqlite3_create_function16()] ** for additional information. ** ** These functions work very much like the ** [sqlite3_bind_blob | sqlite3_bind_*] family of functions used ** to bind values to host parameters in prepared statements. ** Refer to the ** [sqlite3_bind_blob | sqlite3_bind_* documentation] for ** additional information. ** ** The sqlite3_result_blob() interface sets the result from ** an application defined function to be the BLOB whose content is pointed ** to by the second parameter and which is N bytes long where N is the ** third parameter. ** The sqlite3_result_zeroblob() inerfaces set the result of ** the application defined function to be a BLOB containing all zero ** bytes and N bytes in size, where N is the value of the 2nd parameter. ** ** The sqlite3_result_double() interface sets the result from ** an application defined function to be a floating point value specified ** by its 2nd argument. ** ** The sqlite3_result_error() and sqlite3_result_error16() functions ** cause the implemented SQL function to throw an exception. ** SQLite uses the string pointed to by the ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() ** as the text of an error message. SQLite interprets the error ** message string from sqlite3_result_error() as UTF8. SQLite ** interprets the string from sqlite3_result_error16() as UTF16 in native ** byte order. If the third parameter to sqlite3_result_error() ** or sqlite3_result_error16() is negative then SQLite takes as the error ** message all text up through the first zero character. ** If the third parameter to sqlite3_result_error() or ** sqlite3_result_error16() is non-negative then SQLite takes that many ** bytes (not characters) from the 2nd parameter as the error message. ** The sqlite3_result_error() and sqlite3_result_error16() ** routines make a copy private copy of the error message text before ** they return. Hence, the calling function can deallocate or ** modify the text after they return without harm. ** The sqlite3_result_error_code() function changes the error code ** returned by SQLite as a result of an error in a function. By default, ** the error code is SQLITE_ERROR. ** ** The sqlite3_result_toobig() interface causes SQLite ** to throw an error indicating that a string or BLOB is to long ** to represent. The sqlite3_result_nomem() interface ** causes SQLite to throw an exception indicating that the a ** memory allocation failed. ** ** The sqlite3_result_int() interface sets the return value ** of the application-defined function to be the 32-bit signed integer ** value given in the 2nd argument. ** The sqlite3_result_int64() interface sets the return value ** of the application-defined function to be the 64-bit signed integer ** value given in the 2nd argument. ** ** The sqlite3_result_null() interface sets the return value ** of the application-defined function to be NULL. ** ** The sqlite3_result_text(), sqlite3_result_text16(), ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces ** set the return value of the application-defined function to be ** a text string which is represented as UTF-8, UTF-16 native byte order, ** UTF-16 little endian, or UTF-16 big endian, respectively. ** SQLite takes the text result from the application from ** the 2nd parameter of the sqlite3_result_text* interfaces. ** If the 3rd parameter to the sqlite3_result_text* interfaces ** is negative, then SQLite takes result text from the 2nd parameter ** through the first zero character. ** If the 3rd parameter to the sqlite3_result_text* interfaces ** is non-negative, then as many bytes (not characters) of the text ** pointed to by the 2nd parameter are taken as the application-defined ** function result. ** If the 4th parameter to the sqlite3_result_text* interfaces ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that ** function as the destructor on the text or blob result when it has ** finished using that result. ** If the 4th parameter to the sqlite3_result_text* interfaces ** or sqlite3_result_blob is the special constant SQLITE_STATIC, then ** SQLite assumes that the text or blob result is constant space and ** does not copy the space or call a destructor when it has ** finished using that result. ** If the 4th parameter to the sqlite3_result_text* interfaces ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT ** then SQLite makes a copy of the result into space obtained from ** from [sqlite3_malloc()] before it returns. ** ** The sqlite3_result_value() interface sets the result of ** the application-defined function to be a copy the ** [unprotected sqlite3_value] object specified by the 2nd parameter. The ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] ** so that [sqlite3_value] specified in the parameter may change or ** be deallocated after sqlite3_result_value() returns without harm. ** A [protected sqlite3_value] object may always be used where an ** [unprotected sqlite3_value] object is required, so either ** kind of [sqlite3_value] object can be used with this interface. ** ** If these routines are called from within the different thread ** than the one containing the application-defined function that recieved ** the [sqlite3_context] pointer, the results are undefined. ** ** INVARIANTS: ** ** {F16403} The default return value from any SQL function is NULL. ** ** {F16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the ** return value of function C to be a blob that is N bytes ** in length and with content pointed to by V. ** ** {F16409} The [sqlite3_result_double(C,V)] interface changes the ** return value of function C to be the floating point value V. ** ** {F16412} The [sqlite3_result_error(C,V,N)] interface changes the return ** value of function C to be an exception with error code ** [SQLITE_ERROR] and a UTF8 error message copied from V up to the ** first zero byte or until N bytes are read if N is positive. ** ** {F16415} The [sqlite3_result_error16(C,V,N)] interface changes the return ** value of function C to be an exception with error code ** [SQLITE_ERROR] and a UTF16 native byte order error message ** copied from V up to the first zero terminator or until N bytes ** are read if N is positive. ** ** {F16418} The [sqlite3_result_error_toobig(C)] interface changes the return ** value of the function C to be an exception with error code ** [SQLITE_TOOBIG] and an appropriate error message. ** ** {F16421} The [sqlite3_result_error_nomem(C)] interface changes the return ** value of the function C to be an exception with error code ** [SQLITE_NOMEM] and an appropriate error message. ** ** {F16424} The [sqlite3_result_error_code(C,E)] interface changes the return ** value of the function C to be an exception with error code E. ** The error message text is unchanged. ** ** {F16427} The [sqlite3_result_int(C,V)] interface changes the ** return value of function C to be the 32-bit integer value V. ** ** {F16430} The [sqlite3_result_int64(C,V)] interface changes the ** return value of function C to be the 64-bit integer value V. ** ** {F16433} The [sqlite3_result_null(C)] interface changes the ** return value of function C to be NULL. ** ** {F16436} The [sqlite3_result_text(C,V,N,D)] interface changes the ** return value of function C to be the UTF8 string ** V up through the first zero or until N bytes are read if N ** is positive. ** ** {F16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the ** return value of function C to be the UTF16 native byte order ** string V up through the first zero or until N bytes are read if N ** is positive. ** ** {F16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the ** return value of function C to be the UTF16 big-endian ** string V up through the first zero or until N bytes are read if N ** is positive. ** ** {F16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the ** return value of function C to be the UTF16 little-endian ** string V up through the first zero or until N bytes are read if N ** is positive. ** ** {F16448} The [sqlite3_result_value(C,V)] interface changes the ** return value of function C to be [unprotected sqlite3_value] ** object V. ** ** {F16451} The [sqlite3_result_zeroblob(C,N)] interface changes the ** return value of function C to be an N-byte blob of all zeros. ** ** {F16454} The [sqlite3_result_error()] and [sqlite3_result_error16()] ** interfaces make a copy of their error message strings before ** returning. ** ** {F16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], ** [sqlite3_result_text16be(C,V,N,D)], or ** [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC] ** then no destructor is ever called on the pointer V and SQLite ** assumes that V is immutable. ** ** {F16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], ** [sqlite3_result_text16be(C,V,N,D)], or ** [sqlite3_result_text16le(C,V,N,D)] is the constant ** [SQLITE_TRANSIENT] then the interfaces makes a copy of the ** content of V and retains the copy. ** ** {F16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], ** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], ** [sqlite3_result_text16be(C,V,N,D)], or ** [sqlite3_result_text16le(C,V,N,D)] is some value other than ** the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then ** SQLite will invoke the destructor D with V as its only argument ** when it has finished with the V value. */ void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); void sqlite3_result_double(sqlite3_context*, double); void sqlite3_result_error(sqlite3_context*, const char*, int); void sqlite3_result_error16(sqlite3_context*, const void*, int); void sqlite3_result_error_toobig(sqlite3_context*); void sqlite3_result_error_nomem(sqlite3_context*); void sqlite3_result_error_code(sqlite3_context*, int); void sqlite3_result_int(sqlite3_context*, int); void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); void sqlite3_result_null(sqlite3_context*); void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); void sqlite3_result_value(sqlite3_context*, sqlite3_value*); void sqlite3_result_zeroblob(sqlite3_context*, int n); /* ** CAPI3REF: Define New Collating Sequences {F16600} ** ** These functions are used to add new collation sequences to the ** [sqlite3*] handle specified as the first argument. ** ** The name of the new collation sequence is specified as a UTF-8 string ** for sqlite3_create_collation() and sqlite3_create_collation_v2() ** and a UTF-16 string for sqlite3_create_collation16(). In all cases ** the name is passed as the second function argument. ** ** The third argument may be one of the constants [SQLITE_UTF8], ** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied ** routine expects to be passed pointers to strings encoded using UTF-8, ** UTF-16 little-endian or UTF-16 big-endian respectively. The ** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that ** the routine expects pointers to 16-bit word aligned strings ** of UTF16 in the native byte order of the host computer. ** ** A pointer to the user supplied routine must be passed as the fifth ** argument. If it is NULL, this is the same as deleting the collation ** sequence (so that SQLite cannot call it anymore). ** Each time the application ** supplied function is invoked, it is passed a copy of the void* passed as ** the fourth argument to sqlite3_create_collation() or ** sqlite3_create_collation16() as its first parameter. ** ** The remaining arguments to the application-supplied routine are two strings, ** each represented by a (length, data) pair and encoded in the encoding ** that was passed as the third argument when the collation sequence was ** registered. {END} The application defined collation routine should ** return negative, zero or positive if ** the first string is less than, equal to, or greater than the second ** string. i.e. (STRING1 - STRING2). ** ** The sqlite3_create_collation_v2() works like sqlite3_create_collation() ** excapt that it takes an extra argument which is a destructor for ** the collation. The destructor is called when the collation is ** destroyed and is passed a copy of the fourth parameter void* pointer ** of the sqlite3_create_collation_v2(). ** Collations are destroyed when ** they are overridden by later calls to the collation creation functions ** or when the [sqlite3*] database handle is closed using [sqlite3_close()]. ** ** INVARIANTS: ** ** {F16603} A successful call to the ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface ** registers function F as the comparison function used to ** implement collation X on [database connection] B for ** databases having encoding E. ** ** {F16604} SQLite understands the X parameter to ** [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated ** UTF-8 string in which case is ignored for ASCII characters and ** is significant for non-ASCII characters. ** ** {F16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)] ** with the same values for B, X, and E, override prior values ** of P, F, and D. ** ** {F16609} The destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)] ** is not NULL then it is called with argument P when the ** collating function is dropped by SQLite. ** ** {F16612} A collating function is dropped when it is overloaded. ** ** {F16615} A collating function is dropped when the database connection ** is closed using [sqlite3_close()]. ** ** {F16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)] ** is passed through as the first parameter to the comparison ** function F for all subsequent invocations of F. ** ** {F16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly ** the same as a call to [sqlite3_create_collation_v2()] with ** the same parameters and a NULL destructor. ** ** {F16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)], ** SQLite uses the comparison function F for all text comparison ** operations on [database connection] B on text values that ** use the collating sequence name X. ** ** {F16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same ** as [sqlite3_create_collation(B,X,E,P,F)] except that the ** collation name X is understood as UTF-16 in native byte order ** instead of UTF-8. ** ** {F16630} When multiple comparison functions are available for the same ** collating sequence, SQLite chooses the one whose text encoding ** requires the least amount of conversion from the default ** text encoding of the database. */ int sqlite3_create_collation( sqlite3*, const char *zName, int eTextRep, void*, int(*xCompare)(void*,int,const void*,int,const void*) ); int sqlite3_create_collation_v2( sqlite3*, const char *zName, int eTextRep, void*, int(*xCompare)(void*,int,const void*,int,const void*), void(*xDestroy)(void*) ); int sqlite3_create_collation16( sqlite3*, const char *zName, int eTextRep, void*, int(*xCompare)(void*,int,const void*,int,const void*) ); /* ** CAPI3REF: Collation Needed Callbacks {F16700} ** ** To avoid having to register all collation sequences before a database ** can be used, a single callback function may be registered with the ** database handle to be called whenever an undefined collation sequence is ** required. ** ** If the function is registered using the sqlite3_collation_needed() API, ** then it is passed the names of undefined collation sequences as strings ** encoded in UTF-8. {F16703} If sqlite3_collation_needed16() is used, the names ** are passed as UTF-16 in machine native byte order. A call to either ** function replaces any existing callback. ** ** When the callback is invoked, the first argument passed is a copy ** of the second argument to sqlite3_collation_needed() or ** sqlite3_collation_needed16(). The second argument is the database ** handle. The third argument is one of [SQLITE_UTF8], ** [SQLITE_UTF16BE], or [SQLITE_UTF16LE], indicating the most ** desirable form of the collation sequence function required. ** The fourth parameter is the name of the ** required collation sequence. ** ** The callback function should register the desired collation using ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or ** [sqlite3_create_collation_v2()]. ** ** INVARIANTS: ** ** {F16702} A successful call to [sqlite3_collation_needed(D,P,F)] ** or [sqlite3_collation_needed16(D,P,F)] causes ** the [database connection] D to invoke callback F with first ** parameter P whenever it needs a comparison function for a ** collating sequence that it does not know about. ** ** {F16704} Each successful call to [sqlite3_collation_needed()] or ** [sqlite3_collation_needed16()] overrides the callback registered ** on the same [database connection] by prior calls to either ** interface. ** ** {F16706} The name of the requested collating function passed in the ** 4th parameter to the callback is in UTF-8 if the callback ** was registered using [sqlite3_collation_needed()] and ** is in UTF-16 native byte order if the callback was ** registered using [sqlite3_collation_needed16()]. ** ** */ int sqlite3_collation_needed( sqlite3*, void*, void(*)(void*,sqlite3*,int eTextRep,const char*) ); int sqlite3_collation_needed16( sqlite3*, void*, void(*)(void*,sqlite3*,int eTextRep,const void*) ); /* ** Specify the key for an encrypted database. This routine should be ** called right after sqlite3_open(). ** ** The code to implement this API is not available in the public release ** of SQLite. */ int sqlite3_key( sqlite3 *db, /* Database to be rekeyed */ const void *pKey, int nKey /* The key */ ); /* ** Change the key on an open database. If the current database is not ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the ** database is decrypted. ** ** The code to implement this API is not available in the public release ** of SQLite. */ int sqlite3_rekey( sqlite3 *db, /* Database to be rekeyed */ const void *pKey, int nKey /* The new key */ ); /* ** CAPI3REF: Suspend Execution For A Short Time {F10530} ** ** The sqlite3_sleep() function ** causes the current thread to suspend execution ** for at least a number of milliseconds specified in its parameter. ** ** If the operating system does not support sleep requests with ** millisecond time resolution, then the time will be rounded up to ** the nearest second. The number of milliseconds of sleep actually ** requested from the operating system is returned. ** ** SQLite implements this interface by calling the xSleep() ** method of the default [sqlite3_vfs] object. ** ** INVARIANTS: ** ** {F10533} The [sqlite3_sleep(M)] interface invokes the xSleep ** method of the default [sqlite3_vfs|VFS] in order to ** suspend execution of the current thread for at least ** M milliseconds. ** ** {F10536} The [sqlite3_sleep(M)] interface returns the number of ** milliseconds of sleep actually requested of the operating ** system, which might be larger than the parameter M. */ int sqlite3_sleep(int); /* ** CAPI3REF: Name Of The Folder Holding Temporary Files {F10310} ** ** If this global variable is made to point to a string which is ** the name of a folder (a.ka. directory), then all temporary files ** created by SQLite will be placed in that directory. If this variable ** is NULL pointer, then SQLite does a search for an appropriate temporary ** file directory. ** ** It is not safe to modify this variable once a database connection ** has been opened. It is intended that this variable be set once ** as part of process initialization and before any SQLite interface ** routines have been call and remain unchanged thereafter. */ SQLITE_EXTERN char *sqlite3_temp_directory; /* ** CAPI3REF: Test To See If The Database Is In Auto-Commit Mode {F12930} ** ** The sqlite3_get_autocommit() interfaces returns non-zero or ** zero if the given database connection is or is not in autocommit mode, ** respectively. Autocommit mode is on ** by default. Autocommit mode is disabled by a [BEGIN] statement. ** Autocommit mode is reenabled by a [COMMIT] or [ROLLBACK]. ** ** If certain kinds of errors occur on a statement within a multi-statement ** transactions (errors including [SQLITE_FULL], [SQLITE_IOERR], ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the ** transaction might be rolled back automatically. The only way to ** find out if SQLite automatically rolled back the transaction after ** an error is to use this function. ** ** INVARIANTS: ** ** {F12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or ** zero if the [database connection] D is or is not in autocommit ** mode, respectively. ** ** {F12932} Autocommit mode is on by default. ** ** {F12933} Autocommit mode is disabled by a successful [BEGIN] statement. ** ** {F12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK] ** statement. ** ** ** LIMITATIONS: *** ** {U12936} If another thread changes the autocommit status of the database ** connection while this routine is running, then the return value ** is undefined. */ int sqlite3_get_autocommit(sqlite3*); /* ** CAPI3REF: Find The Database Handle Of A Prepared Statement {F13120} ** ** The sqlite3_db_handle interface ** returns the [sqlite3*] database handle to which a ** [prepared statement] belongs. ** The database handle returned by sqlite3_db_handle ** is the same database handle that was ** the first argument to the [sqlite3_prepare_v2()] or its variants ** that was used to create the statement in the first place. ** ** INVARIANTS: ** ** {F13123} The [sqlite3_db_handle(S)] interface returns a pointer ** to the [database connection] associated with ** [prepared statement] S. */ sqlite3 *sqlite3_db_handle(sqlite3_stmt*); /* ** CAPI3REF: Commit And Rollback Notification Callbacks {F12950} ** ** The sqlite3_commit_hook() interface registers a callback ** function to be invoked whenever a transaction is committed. ** Any callback set by a previous call to sqlite3_commit_hook() ** for the same database connection is overridden. ** The sqlite3_rollback_hook() interface registers a callback ** function to be invoked whenever a transaction is committed. ** Any callback set by a previous call to sqlite3_commit_hook() ** for the same database connection is overridden. ** The pArg argument is passed through ** to the callback. If the callback on a commit hook function ** returns non-zero, then the commit is converted into a rollback. ** ** If another function was previously registered, its ** pArg value is returned. Otherwise NULL is returned. ** ** Registering a NULL function disables the callback. ** ** For the purposes of this API, a transaction is said to have been ** rolled back if an explicit "ROLLBACK" statement is executed, or ** an error or constraint causes an implicit rollback to occur. ** The rollback callback is not invoked if a transaction is ** automatically rolled back because the database connection is closed. ** The rollback callback is not invoked if a transaction is ** rolled back because a commit callback returned non-zero. ** <todo> Check on this </todo> ** ** These are experimental interfaces and are subject to change. ** ** INVARIANTS: ** ** {F12951} The [sqlite3_commit_hook(D,F,P)] interface registers the ** callback function F to be invoked with argument P whenever ** a transaction commits on [database connection] D. ** ** {F12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P ** argument from the previous call with the same ** [database connection ] D , or NULL on the first call ** for a particular [database connection] D. ** ** {F12953} Each call to [sqlite3_commit_hook()] overwrites the callback ** registered by prior calls. ** ** {F12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL ** then the commit hook callback is cancelled and no callback ** is invoked when a transaction commits. ** ** {F12955} If the commit callback returns non-zero then the commit is ** converted into a rollback. ** ** {F12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the ** callback function F to be invoked with argument P whenever ** a transaction rolls back on [database connection] D. ** ** {F12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P ** argument from the previous call with the same ** [database connection ] D , or NULL on the first call ** for a particular [database connection] D. ** ** {F12963} Each call to [sqlite3_rollback_hook()] overwrites the callback ** registered by prior calls. ** ** {F12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL ** then the rollback hook callback is cancelled and no callback ** is invoked when a transaction rolls back. */ void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); /* ** CAPI3REF: Data Change Notification Callbacks {F12970} ** ** The sqlite3_update_hook() interface ** registers a callback function with the database connection identified by the ** first argument to be invoked whenever a row is updated, inserted or deleted. ** Any callback set by a previous call to this function for the same ** database connection is overridden. ** ** The second argument is a pointer to the function to invoke when a ** row is updated, inserted or deleted. ** The first argument to the callback is ** a copy of the third argument to sqlite3_update_hook(). ** The second callback ** argument is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], ** depending on the operation that caused the callback to be invoked. ** The third and ** fourth arguments to the callback contain pointers to the database and ** table name containing the affected row. ** The final callback parameter is ** the rowid of the row. ** In the case of an update, this is the rowid after ** the update takes place. ** ** The update hook is not invoked when internal system tables are ** modified (i.e. sqlite_master and sqlite_sequence). ** ** If another function was previously registered, its pArg value ** is returned. Otherwise NULL is returned. ** ** INVARIANTS: ** ** {F12971} The [sqlite3_update_hook(D,F,P)] interface causes callback ** function F to be invoked with first parameter P whenever ** a table row is modified, inserted, or deleted on ** [database connection] D. ** ** {F12973} The [sqlite3_update_hook(D,F,P)] interface returns the value ** of P for the previous call on the same [database connection] D, ** or NULL for the first call. ** ** {F12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)] ** is NULL then the no update callbacks are made. ** ** {F12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls ** to the same interface on the same [database connection] D. ** ** {F12979} The update hook callback is not invoked when internal system ** tables such as sqlite_master and sqlite_sequence are modified. ** ** {F12981} The second parameter to the update callback ** is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], ** depending on the operation that caused the callback to be invoked. ** ** {F12983} The third and fourth arguments to the callback contain pointers ** to zero-terminated UTF-8 strings which are the names of the ** database and table that is being updated. ** {F12985} The final callback parameter is the rowid of the row after ** the change occurs. */ void *sqlite3_update_hook( sqlite3*, void(*)(void *,int ,char const *,char const *,sqlite3_int64), void* ); /* ** CAPI3REF: Enable Or Disable Shared Pager Cache {F10330} ** ** This routine enables or disables the sharing of the database cache ** and schema data structures between connections to the same database. ** Sharing is enabled if the argument is true and disabled if the argument ** is false. ** ** Cache sharing is enabled and disabled ** for an entire process. {END} This is a change as of SQLite version 3.5.0. ** In prior versions of SQLite, sharing was ** enabled or disabled for each thread separately. ** ** The cache sharing mode set by this interface effects all subsequent ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. ** Existing database connections continue use the sharing mode ** that was in effect at the time they were opened. ** ** Virtual tables cannot be used with a shared cache. When shared ** cache is enabled, the [sqlite3_create_module()] API used to register ** virtual tables will always return an error. ** ** This routine returns [SQLITE_OK] if shared cache was ** enabled or disabled successfully. An [error code] ** is returned otherwise. ** ** Shared cache is disabled by default. But this might change in ** future releases of SQLite. Applications that care about shared ** cache setting should set it explicitly. ** ** INVARIANTS: ** ** {F10331} A successful invocation of [sqlite3_enable_shared_cache(B)] ** will enable or disable shared cache mode for any subsequently ** created [database connection] in the same process. ** ** {F10336} When shared cache is enabled, the [sqlite3_create_module()] ** interface will always return an error. ** ** {F10337} The [sqlite3_enable_shared_cache(B)] interface returns ** [SQLITE_OK] if shared cache was enabled or disabled successfully. ** ** {F10339} Shared cache is disabled by default. */ int sqlite3_enable_shared_cache(int); /* ** CAPI3REF: Attempt To Free Heap Memory {F17340} ** ** The sqlite3_release_memory() interface attempts to ** free N bytes of heap memory by deallocating non-essential memory ** allocations held by the database labrary. {END} Memory used ** to cache database pages to improve performance is an example of ** non-essential memory. Sqlite3_release_memory() returns ** the number of bytes actually freed, which might be more or less ** than the amount requested. ** ** INVARIANTS: ** ** {F17341} The [sqlite3_release_memory(N)] interface attempts to ** free N bytes of heap memory by deallocating non-essential ** memory allocations held by the database labrary. ** ** {F16342} The [sqlite3_release_memory(N)] returns the number ** of bytes actually freed, which might be more or less ** than the amount requested. */ int sqlite3_release_memory(int); /* ** CAPI3REF: Impose A Limit On Heap Size {F17350} ** ** The sqlite3_soft_heap_limit() interface ** places a "soft" limit on the amount of heap memory that may be allocated ** by SQLite. If an internal allocation is requested ** that would exceed the soft heap limit, [sqlite3_release_memory()] is ** invoked one or more times to free up some space before the allocation ** is made. ** ** The limit is called "soft", because if ** [sqlite3_release_memory()] cannot ** free sufficient memory to prevent the limit from being exceeded, ** the memory is allocated anyway and the current operation proceeds. ** ** A negative or zero value for N means that there is no soft heap limit and ** [sqlite3_release_memory()] will only be called when memory is exhausted. ** The default value for the soft heap limit is zero. ** ** SQLite makes a best effort to honor the soft heap limit. ** But if the soft heap limit cannot honored, execution will ** continue without error or notification. This is why the limit is ** called a "soft" limit. It is advisory only. ** ** Prior to SQLite version 3.5.0, this routine only constrained the memory ** allocated by a single thread - the same thread in which this routine ** runs. Beginning with SQLite version 3.5.0, the soft heap limit is ** applied to all threads. The value specified for the soft heap limit ** is an upper bound on the total memory allocation for all threads. In ** version 3.5.0 there is no mechanism for limiting the heap usage for ** individual threads. ** ** INVARIANTS: ** ** {F16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit ** of N bytes on the amount of heap memory that may be allocated ** using [sqlite3_malloc()] or [sqlite3_realloc()] at any point ** in time. ** ** {F16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would ** cause the total amount of allocated memory to exceed the ** soft heap limit, then [sqlite3_release_memory()] is invoked ** in an attempt to reduce the memory usage prior to proceeding ** with the memory allocation attempt. ** ** {F16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger ** attempts to reduce memory usage through the soft heap limit ** mechanism continue even if the attempt to reduce memory ** usage is unsuccessful. ** ** {F16354} A negative or zero value for N in a call to ** [sqlite3_soft_heap_limit(N)] means that there is no soft ** heap limit and [sqlite3_release_memory()] will only be ** called when memory is completely exhausted. ** ** {F16355} The default value for the soft heap limit is zero. ** ** {F16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the ** values set by all prior calls. */ void sqlite3_soft_heap_limit(int); /* ** CAPI3REF: Extract Metadata About A Column Of A Table {F12850} ** ** This routine ** returns meta-data about a specific column of a specific database ** table accessible using the connection handle passed as the first function ** argument. ** ** The column is identified by the second, third and fourth parameters to ** this function. The second parameter is either the name of the database ** (i.e. "main", "temp" or an attached database) containing the specified ** table or NULL. If it is NULL, then all attached databases are searched ** for the table using the same algorithm as the database engine uses to ** resolve unqualified table references. ** ** The third and fourth parameters to this function are the table and column ** name of the desired column, respectively. Neither of these parameters ** may be NULL. ** ** Meta information is returned by writing to the memory locations passed as ** the 5th and subsequent parameters to this function. Any of these ** arguments may be NULL, in which case the corresponding element of meta ** information is ommitted. ** ** <pre> ** Parameter Output Type Description ** ----------------------------------- ** ** 5th const char* Data type ** 6th const char* Name of the default collation sequence ** 7th int True if the column has a NOT NULL constraint ** 8th int True if the column is part of the PRIMARY KEY ** 9th int True if the column is AUTOINCREMENT ** </pre> ** ** ** The memory pointed to by the character pointers returned for the ** declaration type and collation sequence is valid only until the next ** call to any sqlite API function. ** ** If the specified table is actually a view, then an error is returned. ** ** If the specified column is "rowid", "oid" or "_rowid_" and an ** INTEGER PRIMARY KEY column has been explicitly declared, then the output ** parameters are set for the explicitly declared column. If there is no ** explicitly declared IPK column, then the output parameters are set as ** follows: ** ** <pre> ** data type: "INTEGER" ** collation sequence: "BINARY" ** not null: 0 ** primary key: 1 ** auto increment: 0 ** </pre> ** ** This function may load one or more schemas from database files. If an ** error occurs during this process, or if the requested table or column ** cannot be found, an SQLITE error code is returned and an error message ** left in the database handle (to be retrieved using sqlite3_errmsg()). ** ** This API is only available if the library was compiled with the ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined. */ int sqlite3_table_column_metadata( sqlite3 *db, /* Connection handle */ const char *zDbName, /* Database name or NULL */ const char *zTableName, /* Table name */ const char *zColumnName, /* Column name */ char const **pzDataType, /* OUTPUT: Declared data type */ char const **pzCollSeq, /* OUTPUT: Collation sequence name */ int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ int *pPrimaryKey, /* OUTPUT: True if column part of PK */ int *pAutoinc /* OUTPUT: True if column is auto-increment */ ); /* ** CAPI3REF: Load An Extension {F12600} ** ** {F12601} The sqlite3_load_extension() interface ** attempts to load an SQLite extension library contained in the file ** zFile. {F12602} The entry point is zProc. {F12603} zProc may be 0 ** in which case the name of the entry point defaults ** to "sqlite3_extension_init". ** ** {F12604} The sqlite3_load_extension() interface shall ** return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. ** ** {F12605} ** If an error occurs and pzErrMsg is not 0, then the ** sqlite3_load_extension() interface shall attempt to fill *pzErrMsg with ** error message text stored in memory obtained from [sqlite3_malloc()]. ** {END} The calling function should free this memory ** by calling [sqlite3_free()]. ** ** {F12606} ** Extension loading must be enabled using [sqlite3_enable_load_extension()] ** prior to calling this API or an error will be returned. */ int sqlite3_load_extension( sqlite3 *db, /* Load the extension into this database connection */ const char *zFile, /* Name of the shared library containing extension */ const char *zProc, /* Entry point. Derived from zFile if 0 */ char **pzErrMsg /* Put error message here if not 0 */ ); /* ** CAPI3REF: Enable Or Disable Extension Loading {F12620} ** ** So as not to open security holes in older applications that are ** unprepared to deal with extension loading, and as a means of disabling ** extension loading while evaluating user-entered SQL, the following ** API is provided to turn the [sqlite3_load_extension()] mechanism on and ** off. {F12622} It is off by default. {END} See ticket #1863. ** ** {F12621} Call the sqlite3_enable_load_extension() routine ** with onoff==1 to turn extension loading on ** and call it with onoff==0 to turn it back off again. {END} */ int sqlite3_enable_load_extension(sqlite3 *db, int onoff); /* ** CAPI3REF: Make Arrangements To Automatically Load An Extension {F12640} ** ** {F12641} This function ** registers an extension entry point that is automatically invoked ** whenever a new database connection is opened using ** [sqlite3_open()], [sqlite3_open16()], or [sqlite3_open_v2()]. {END} ** ** This API can be invoked at program startup in order to register ** one or more statically linked extensions that will be available ** to all new database connections. ** ** {F12642} Duplicate extensions are detected so calling this routine multiple ** times with the same extension is harmless. ** ** {F12643} This routine stores a pointer to the extension in an array ** that is obtained from sqlite_malloc(). {END} If you run a memory leak ** checker on your program and it reports a leak because of this ** array, then invoke [sqlite3_reset_auto_extension()] prior ** to shutdown to free the memory. ** ** {F12644} Automatic extensions apply across all threads. {END} ** ** This interface is experimental and is subject to change or ** removal in future releases of SQLite. */ int sqlite3_auto_extension(void *xEntryPoint); /* ** CAPI3REF: Reset Automatic Extension Loading {F12660} ** ** {F12661} This function disables all previously registered ** automatic extensions. {END} This ** routine undoes the effect of all prior [sqlite3_auto_extension()] ** calls. ** ** {F12662} This call disabled automatic extensions in all threads. {END} ** ** This interface is experimental and is subject to change or ** removal in future releases of SQLite. */ void sqlite3_reset_auto_extension(void); /* ****** EXPERIMENTAL - subject to change without notice ************** ** ** The interface to the virtual-table mechanism is currently considered ** to be experimental. The interface might change in incompatible ways. ** If this is a problem for you, do not use the interface at this time. ** ** When the virtual-table mechanism stablizes, we will declare the ** interface fixed, support it indefinitely, and remove this comment. */ /* ** Structures used by the virtual table interface */ typedef struct sqlite3_vtab sqlite3_vtab; typedef struct sqlite3_index_info sqlite3_index_info; typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; typedef struct sqlite3_module sqlite3_module; /* ** CAPI3REF: Virtual Table Object {F18000} ** KEYWORDS: sqlite3_module ** ** A module is a class of virtual tables. Each module is defined ** by an instance of the following structure. This structure consists ** mostly of methods for the module. */ struct sqlite3_module { int iVersion; int (*xCreate)(sqlite3*, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char**); int (*xConnect)(sqlite3*, void *pAux, int argc, const char *const*argv, sqlite3_vtab **ppVTab, char**); int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); int (*xDisconnect)(sqlite3_vtab *pVTab); int (*xDestroy)(sqlite3_vtab *pVTab); int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); int (*xClose)(sqlite3_vtab_cursor*); int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, int argc, sqlite3_value **argv); int (*xNext)(sqlite3_vtab_cursor*); int (*xEof)(sqlite3_vtab_cursor*); int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); int (*xBegin)(sqlite3_vtab *pVTab); int (*xSync)(sqlite3_vtab *pVTab); int (*xCommit)(sqlite3_vtab *pVTab); int (*xRollback)(sqlite3_vtab *pVTab); int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), void **ppArg); int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); }; /* ** CAPI3REF: Virtual Table Indexing Information {F18100} ** KEYWORDS: sqlite3_index_info ** ** The sqlite3_index_info structure and its substructures is used to ** pass information into and receive the reply from the xBestIndex ** method of an sqlite3_module. The fields under **Inputs** are the ** inputs to xBestIndex and are read-only. xBestIndex inserts its ** results into the **Outputs** fields. ** ** The aConstraint[] array records WHERE clause constraints of the ** form: ** ** column OP expr ** ** Where OP is =, <, <=, >, or >=. ** The particular operator is stored ** in aConstraint[].op. The index of the column is stored in ** aConstraint[].iColumn. aConstraint[].usable is TRUE if the ** expr on the right-hand side can be evaluated (and thus the constraint ** is usable) and false if it cannot. ** ** The optimizer automatically inverts terms of the form "expr OP column" ** and makes other simplifications to the WHERE clause in an attempt to ** get as many WHERE clause terms into the form shown above as possible. ** The aConstraint[] array only reports WHERE clause terms in the correct ** form that refer to the particular virtual table being queried. ** ** Information about the ORDER BY clause is stored in aOrderBy[]. ** Each term of aOrderBy records a column of the ORDER BY clause. ** ** The xBestIndex method must fill aConstraintUsage[] with information ** about what parameters to pass to xFilter. If argvIndex>0 then ** the right-hand side of the corresponding aConstraint[] is evaluated ** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit ** is true, then the constraint is assumed to be fully handled by the ** virtual table and is not checked again by SQLite. ** ** The idxNum and idxPtr values are recorded and passed into xFilter. ** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true. ** ** The orderByConsumed means that output from xFilter will occur in ** the correct order to satisfy the ORDER BY clause so that no separate ** sorting step is required. ** ** The estimatedCost value is an estimate of the cost of doing the ** particular lookup. A full scan of a table with N entries should have ** a cost of N. A binary search of a table of N entries should have a ** cost of approximately log(N). */ struct sqlite3_index_info { /* Inputs */ int nConstraint; /* Number of entries in aConstraint */ struct sqlite3_index_constraint { int iColumn; /* Column on left-hand side of constraint */ unsigned char op; /* Constraint operator */ unsigned char usable; /* True if this constraint is usable */ int iTermOffset; /* Used internally - xBestIndex should ignore */ } *aConstraint; /* Table of WHERE clause constraints */ int nOrderBy; /* Number of terms in the ORDER BY clause */ struct sqlite3_index_orderby { int iColumn; /* Column number */ unsigned char desc; /* True for DESC. False for ASC. */ } *aOrderBy; /* The ORDER BY clause */ /* Outputs */ struct sqlite3_index_constraint_usage { int argvIndex; /* if >0, constraint is part of argv to xFilter */ unsigned char omit; /* Do not code a test for this constraint */ } *aConstraintUsage; int idxNum; /* Number used to identify the index */ char *idxStr; /* String, possibly obtained from sqlite3_malloc */ int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ int orderByConsumed; /* True if output is already ordered */ double estimatedCost; /* Estimated cost of using this index */ }; #define SQLITE_INDEX_CONSTRAINT_EQ 2 #define SQLITE_INDEX_CONSTRAINT_GT 4 #define SQLITE_INDEX_CONSTRAINT_LE 8 #define SQLITE_INDEX_CONSTRAINT_LT 16 #define SQLITE_INDEX_CONSTRAINT_GE 32 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 /* ** CAPI3REF: Register A Virtual Table Implementation {F18200} ** ** This routine is used to register a new module name with an SQLite ** connection. Module names must be registered before creating new ** virtual tables on the module, or before using preexisting virtual ** tables of the module. */ int sqlite3_create_module( sqlite3 *db, /* SQLite connection to register module with */ const char *zName, /* Name of the module */ const sqlite3_module *, /* Methods for the module */ void * /* Client data for xCreate/xConnect */ ); /* ** CAPI3REF: Register A Virtual Table Implementation {F18210} ** ** This routine is identical to the sqlite3_create_module() method above, ** except that it allows a destructor function to be specified. It is ** even more experimental than the rest of the virtual tables API. */ int sqlite3_create_module_v2( sqlite3 *db, /* SQLite connection to register module with */ const char *zName, /* Name of the module */ const sqlite3_module *, /* Methods for the module */ void *, /* Client data for xCreate/xConnect */ void(*xDestroy)(void*) /* Module destructor function */ ); /* ** CAPI3REF: Virtual Table Instance Object {F18010} ** KEYWORDS: sqlite3_vtab ** ** Every module implementation uses a subclass of the following structure ** to describe a particular instance of the module. Each subclass will ** be tailored to the specific needs of the module implementation. The ** purpose of this superclass is to define certain fields that are common ** to all module implementations. ** ** Virtual tables methods can set an error message by assigning a ** string obtained from sqlite3_mprintf() to zErrMsg. The method should ** take care that any prior string is freed by a call to sqlite3_free() ** prior to assigning a new string to zErrMsg. After the error message ** is delivered up to the client application, the string will be automatically ** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note ** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field ** since virtual tables are commonly implemented in loadable extensions which ** do not have access to sqlite3MPrintf() or sqlite3Free(). */ struct sqlite3_vtab { const sqlite3_module *pModule; /* The module for this virtual table */ int nRef; /* Used internally */ char *zErrMsg; /* Error message from sqlite3_mprintf() */ /* Virtual table implementations will typically add additional fields */ }; /* ** CAPI3REF: Virtual Table Cursor Object {F18020} ** KEYWORDS: sqlite3_vtab_cursor ** ** Every module implementation uses a subclass of the following structure ** to describe cursors that point into the virtual table and are used ** to loop through the virtual table. Cursors are created using the ** xOpen method of the module. Each module implementation will define ** the content of a cursor structure to suit its own needs. ** ** This superclass exists in order to define fields of the cursor that ** are common to all implementations. */ struct sqlite3_vtab_cursor { sqlite3_vtab *pVtab; /* Virtual table of this cursor */ /* Virtual table implementations will typically add additional fields */ }; /* ** CAPI3REF: Declare The Schema Of A Virtual Table {F18280} ** ** The xCreate and xConnect methods of a module use the following API ** to declare the format (the names and datatypes of the columns) of ** the virtual tables they implement. */ int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable); /* ** CAPI3REF: Overload A Function For A Virtual Table {F18300} ** ** Virtual tables can provide alternative implementations of functions ** using the xFindFunction method. But global versions of those functions ** must exist in order to be overloaded. ** ** This API makes sure a global version of a function with a particular ** name and number of parameters exists. If no such function exists ** before this API is called, a new function is created. The implementation ** of the new function always causes an exception to be thrown. So ** the new function is not good for anything by itself. Its only ** purpose is to be a place-holder function that can be overloaded ** by virtual tables. ** ** This API should be considered part of the virtual table interface, ** which is experimental and subject to change. */ int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); /* ** The interface to the virtual-table mechanism defined above (back up ** to a comment remarkably similar to this one) is currently considered ** to be experimental. The interface might change in incompatible ways. ** If this is a problem for you, do not use the interface at this time. ** ** When the virtual-table mechanism stabilizes, we will declare the ** interface fixed, support it indefinitely, and remove this comment. ** ****** EXPERIMENTAL - subject to change without notice ************** */ /* ** CAPI3REF: A Handle To An Open BLOB {F17800} ** ** An instance of this object represents an open BLOB on which ** incremental I/O can be preformed. ** Objects of this type are created by ** [sqlite3_blob_open()] and destroyed by [sqlite3_blob_close()]. ** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces ** can be used to read or write small subsections of the blob. ** The [sqlite3_blob_bytes()] interface returns the size of the ** blob in bytes. */ typedef struct sqlite3_blob sqlite3_blob; /* ** CAPI3REF: Open A BLOB For Incremental I/O {F17810} ** ** This interfaces opens a handle to the blob located ** in row iRow,, column zColumn, table zTable in database zDb; ** in other words, the same blob that would be selected by: ** ** <pre> ** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow; ** </pre> {END} ** ** If the flags parameter is non-zero, the blob is opened for ** read and write access. If it is zero, the blob is opened for read ** access. ** ** On success, [SQLITE_OK] is returned and the new ** [sqlite3_blob | blob handle] is written to *ppBlob. ** Otherwise an error code is returned and ** any value written to *ppBlob should not be used by the caller. ** This function sets the database-handle error code and message ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()]. ** ** INVARIANTS: ** ** {F17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)] ** interface opens an [sqlite3_blob] object P on the blob ** in column C of table T in database B on [database connection] D. ** ** {F17814} A successful invocation of [sqlite3_blob_open(D,...)] starts ** a new transaction on [database connection] D if that connection ** is not already in a transaction. ** ** {F17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface opens the blob ** for read and write access if and only if the F parameter ** is non-zero. ** ** {F17819} The [sqlite3_blob_open()] interface returns [SQLITE_OK] on ** success and an appropriate [error code] on failure. ** ** {F17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)] ** then subsequent calls to [sqlite3_errcode(D)], ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return ** information approprate for that error. */ int sqlite3_blob_open( sqlite3*, const char *zDb, const char *zTable, const char *zColumn, sqlite3_int64 iRow, int flags, sqlite3_blob **ppBlob ); /* ** CAPI3REF: Close A BLOB Handle {F17830} ** ** Close an open [sqlite3_blob | blob handle]. ** ** Closing a BLOB shall cause the current transaction to commit ** if there are no other BLOBs, no pending prepared statements, and the ** database connection is in autocommit mode. ** If any writes were made to the BLOB, they might be held in cache ** until the close operation if they will fit. {END} ** Closing the BLOB often forces the changes ** out to disk and so if any I/O errors occur, they will likely occur ** at the time when the BLOB is closed. {F17833} Any errors that occur during ** closing are reported as a non-zero return value. ** ** The BLOB is closed unconditionally. Even if this routine returns ** an error code, the BLOB is still closed. ** ** INVARIANTS: ** ** {F17833} The [sqlite3_blob_close(P)] interface closes an ** [sqlite3_blob] object P previously opened using ** [sqlite3_blob_open()]. ** ** {F17836} Closing an [sqlite3_blob] object using ** [sqlite3_blob_close()] shall cause the current transaction to ** commit if there are no other open [sqlite3_blob] objects ** or [prepared statements] on the same [database connection] and ** the [database connection] is in ** [sqlite3_get_autocommit | autocommit mode]. ** ** {F17839} The [sqlite3_blob_close(P)] interfaces closes the ** [sqlite3_blob] object P unconditionally, even if ** [sqlite3_blob_close(P)] returns something other than [SQLITE_OK]. ** */ int sqlite3_blob_close(sqlite3_blob *); /* ** CAPI3REF: Return The Size Of An Open BLOB {F17840} ** ** Return the size in bytes of the blob accessible via the open ** [sqlite3_blob] object in its only argument. ** ** INVARIANTS: ** ** {F17843} The [sqlite3_blob_bytes(P)] interface returns the size ** in bytes of the BLOB that the [sqlite3_blob] object P ** refers to. */ int sqlite3_blob_bytes(sqlite3_blob *); /* ** CAPI3REF: Read Data From A BLOB Incrementally {F17850} ** ** This function is used to read data from an open ** [sqlite3_blob | blob-handle] into a caller supplied buffer. ** N bytes of data are copied into buffer ** Z from the open blob, starting at offset iOffset. ** ** If offset iOffset is less than N bytes from the end of the blob, ** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is ** less than zero [SQLITE_ERROR] is returned and no data is read. ** ** On success, SQLITE_OK is returned. Otherwise, an ** [error code] or an [extended error code] is returned. ** ** INVARIANTS: ** ** {F17853} The [sqlite3_blob_read(P,Z,N,X)] interface reads N bytes ** beginning at offset X from ** the blob that [sqlite3_blob] object P refers to ** and writes those N bytes into buffer Z. ** ** {F17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the blob ** is less than N+X bytes, then the function returns [SQLITE_ERROR] ** and nothing is read from the blob. ** ** {F17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero ** then the function returns [SQLITE_ERROR] ** and nothing is read from the blob. ** ** {F17862} The [sqlite3_blob_read(P,Z,N,X)] interface returns [SQLITE_OK] ** if N bytes where successfully read into buffer Z. ** ** {F17865} If the requested read could not be completed, ** the [sqlite3_blob_read(P,Z,N,X)] interface returns an ** appropriate [error code] or [extended error code]. ** ** {F17868} If an error occurs during evaluation of [sqlite3_blob_read(D,...)] ** then subsequent calls to [sqlite3_errcode(D)], ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return ** information approprate for that error. */ int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); /* ** CAPI3REF: Write Data Into A BLOB Incrementally {F17870} ** ** This function is used to write data into an open ** [sqlite3_blob | blob-handle] from a user supplied buffer. ** n bytes of data are copied from the buffer ** pointed to by z into the open blob, starting at offset iOffset. ** ** If the [sqlite3_blob | blob-handle] passed as the first argument ** was not opened for writing (the flags parameter to [sqlite3_blob_open()] *** was zero), this function returns [SQLITE_READONLY]. ** ** This function may only modify the contents of the blob; it is ** not possible to increase the size of a blob using this API. ** If offset iOffset is less than n bytes from the end of the blob, ** [SQLITE_ERROR] is returned and no data is written. If n is ** less than zero [SQLITE_ERROR] is returned and no data is written. ** ** On success, SQLITE_OK is returned. Otherwise, an ** [error code] or an [extended error code] is returned. ** ** INVARIANTS: ** ** {F17873} The [sqlite3_blob_write(P,Z,N,X)] interface writes N bytes ** from buffer Z into ** the blob that [sqlite3_blob] object P refers to ** beginning at an offset of X into the blob. ** ** {F17875} The [sqlite3_blob_write(P,Z,N,X)] interface returns ** [SQLITE_READONLY] if the [sqlite3_blob] object P was ** [sqlite3_blob_open | opened] for reading only. ** ** {F17876} In [sqlite3_blob_write(P,Z,N,X)] if the size of the blob ** is less than N+X bytes, then the function returns [SQLITE_ERROR] ** and nothing is written into the blob. ** ** {F17879} In [sqlite3_blob_write(P,Z,N,X)] if X or N is less than zero ** then the function returns [SQLITE_ERROR] ** and nothing is written into the blob. ** ** {F17882} The [sqlite3_blob_write(P,Z,N,X)] interface returns [SQLITE_OK] ** if N bytes where successfully written into blob. ** ** {F17885} If the requested write could not be completed, ** the [sqlite3_blob_write(P,Z,N,X)] interface returns an ** appropriate [error code] or [extended error code]. ** ** {F17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)] ** then subsequent calls to [sqlite3_errcode(D)], ** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] will return ** information approprate for that error. */ int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); /* ** CAPI3REF: Virtual File System Objects {F11200} ** ** A virtual filesystem (VFS) is an [sqlite3_vfs] object ** that SQLite uses to interact ** with the underlying operating system. Most SQLite builds come with a ** single default VFS that is appropriate for the host computer. ** New VFSes can be registered and existing VFSes can be unregistered. ** The following interfaces are provided. ** ** The sqlite3_vfs_find() interface returns a pointer to ** a VFS given its name. Names are case sensitive. ** Names are zero-terminated UTF-8 strings. ** If there is no match, a NULL ** pointer is returned. If zVfsName is NULL then the default ** VFS is returned. ** ** New VFSes are registered with sqlite3_vfs_register(). ** Each new VFS becomes the default VFS if the makeDflt flag is set. ** The same VFS can be registered multiple times without injury. ** To make an existing VFS into the default VFS, register it again ** with the makeDflt flag set. If two different VFSes with the ** same name are registered, the behavior is undefined. If a ** VFS is registered with a name that is NULL or an empty string, ** then the behavior is undefined. ** ** Unregister a VFS with the sqlite3_vfs_unregister() interface. ** If the default VFS is unregistered, another VFS is chosen as ** the default. The choice for the new VFS is arbitrary. ** ** INVARIANTS: ** ** {F11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the ** registered [sqlite3_vfs] object whose name exactly matches ** the zero-terminated UTF-8 string N, or it returns NULL if ** there is no match. ** ** {F11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then ** the function returns a pointer to the default [sqlite3_vfs] ** object if there is one, or NULL if there is no default ** [sqlite3_vfs] object. ** ** {F11209} The [sqlite3_vfs_register(P,F)] interface registers the ** well-formed [sqlite3_vfs] object P using the name given ** by the zName field of the object. ** ** {F11212} Using the [sqlite3_vfs_register(P,F)] interface to register ** the same [sqlite3_vfs] object multiple times is a harmless no-op. ** ** {F11215} The [sqlite3_vfs_register(P,F)] interface makes the ** the [sqlite3_vfs] object P the default [sqlite3_vfs] object ** if F is non-zero. ** ** {F11218} The [sqlite3_vfs_unregister(P)] interface unregisters the ** [sqlite3_vfs] object P so that it is no longer returned by ** subsequent calls to [sqlite3_vfs_find()]. */ sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); int sqlite3_vfs_unregister(sqlite3_vfs*); /* ** CAPI3REF: Mutexes {F17000} ** ** The SQLite core uses these routines for thread ** synchronization. Though they are intended for internal ** use by SQLite, code that links against SQLite is ** permitted to use any of these routines. ** ** The SQLite source code contains multiple implementations ** of these mutex routines. An appropriate implementation ** is selected automatically at compile-time. The following ** implementations are available in the SQLite core: ** ** <ul> ** <li> SQLITE_MUTEX_OS2 ** <li> SQLITE_MUTEX_PTHREAD ** <li> SQLITE_MUTEX_W32 ** <li> SQLITE_MUTEX_NOOP ** </ul> ** ** The SQLITE_MUTEX_NOOP implementation is a set of routines ** that does no real locking and is appropriate for use in ** a single-threaded application. The SQLITE_MUTEX_OS2, ** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations ** are appropriate for use on os/2, unix, and windows. ** ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex ** implementation is included with the library. The ** mutex interface routines defined here become external ** references in the SQLite library for which implementations ** must be provided by the application. This facility allows an ** application that links against SQLite to provide its own mutex ** implementation without having to modify the SQLite core. ** ** {F17011} The sqlite3_mutex_alloc() routine allocates a new ** mutex and returns a pointer to it. {F17012} If it returns NULL ** that means that a mutex could not be allocated. {F17013} SQLite ** will unwind its stack and return an error. {F17014} The argument ** to sqlite3_mutex_alloc() is one of these integer constants: ** ** <ul> ** <li> SQLITE_MUTEX_FAST ** <li> SQLITE_MUTEX_RECURSIVE ** <li> SQLITE_MUTEX_STATIC_MASTER ** <li> SQLITE_MUTEX_STATIC_MEM ** <li> SQLITE_MUTEX_STATIC_MEM2 ** <li> SQLITE_MUTEX_STATIC_PRNG ** <li> SQLITE_MUTEX_STATIC_LRU ** </ul> {END} ** ** {F17015} The first two constants cause sqlite3_mutex_alloc() to create ** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END} ** The mutex implementation does not need to make a distinction ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does ** not want to. {F17016} But SQLite will only request a recursive mutex in ** cases where it really needs one. {END} If a faster non-recursive mutex ** implementation is available on the host platform, the mutex subsystem ** might return such a mutex in response to SQLITE_MUTEX_FAST. ** ** {F17017} The other allowed parameters to sqlite3_mutex_alloc() each return ** a pointer to a static preexisting mutex. {END} Four static mutexes are ** used by the current version of SQLite. Future versions of SQLite ** may add additional static mutexes. Static mutexes are for internal ** use by SQLite only. Applications that use SQLite mutexes should ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or ** SQLITE_MUTEX_RECURSIVE. ** ** {F17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() ** returns a different mutex on every call. {F17034} But for the static ** mutex types, the same mutex is returned on every call that has ** the same type number. {END} ** ** {F17019} The sqlite3_mutex_free() routine deallocates a previously ** allocated dynamic mutex. {F17020} SQLite is careful to deallocate every ** dynamic mutex that it allocates. {U17021} The dynamic mutexes must not be in ** use when they are deallocated. {U17022} Attempting to deallocate a static ** mutex results in undefined behavior. {F17023} SQLite never deallocates ** a static mutex. {END} ** ** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt ** to enter a mutex. {F17024} If another thread is already within the mutex, ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return ** SQLITE_BUSY. {F17025} The sqlite3_mutex_try() interface returns SQLITE_OK ** upon successful entry. {F17026} Mutexes created using ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. ** {F17027} In such cases the, ** mutex must be exited an equal number of times before another thread ** can enter. {U17028} If the same thread tries to enter any other ** kind of mutex more than once, the behavior is undefined. ** {F17029} SQLite will never exhibit ** such behavior in its own use of mutexes. {END} ** ** Some systems (ex: windows95) do not the operation implemented by ** sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() will ** always return SQLITE_BUSY. {F17030} The SQLite core only ever uses ** sqlite3_mutex_try() as an optimization so this is acceptable behavior. {END} ** ** {F17031} The sqlite3_mutex_leave() routine exits a mutex that was ** previously entered by the same thread. {U17032} The behavior ** is undefined if the mutex is not currently entered by the ** calling thread or is not currently allocated. {F17033} SQLite will ** never do either. {END} ** ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. */ sqlite3_mutex *sqlite3_mutex_alloc(int); void sqlite3_mutex_free(sqlite3_mutex*); void sqlite3_mutex_enter(sqlite3_mutex*); int sqlite3_mutex_try(sqlite3_mutex*); void sqlite3_mutex_leave(sqlite3_mutex*); /* ** CAPI3REF: Mutex Verifcation Routines {F17080} ** ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines ** are intended for use inside assert() statements. {F17081} The SQLite core ** never uses these routines except inside an assert() and applications ** are advised to follow the lead of the core. {F17082} The core only ** provides implementations for these routines when it is compiled ** with the SQLITE_DEBUG flag. {U17087} External mutex implementations ** are only required to provide these routines if SQLITE_DEBUG is ** defined and if NDEBUG is not defined. ** ** {F17083} These routines should return true if the mutex in their argument ** is held or not held, respectively, by the calling thread. {END} ** ** {X17084} The implementation is not required to provided versions of these ** routines that actually work. ** If the implementation does not provide working ** versions of these routines, it should at least provide stubs ** that always return true so that one does not get spurious ** assertion failures. {END} ** ** {F17085} If the argument to sqlite3_mutex_held() is a NULL pointer then ** the routine should return 1. {END} This seems counter-intuitive since ** clearly the mutex cannot be held if it does not exist. But the ** the reason the mutex does not exist is because the build is not ** using mutexes. And we do not want the assert() containing the ** call to sqlite3_mutex_held() to fail, so a non-zero return is ** the appropriate thing to do. {F17086} The sqlite3_mutex_notheld() ** interface should also return 1 when given a NULL pointer. */ int sqlite3_mutex_held(sqlite3_mutex*); int sqlite3_mutex_notheld(sqlite3_mutex*); /* ** CAPI3REF: Mutex Types {F17001} ** ** {F17002} The [sqlite3_mutex_alloc()] interface takes a single argument ** which is one of these integer constants. {END} */ #define SQLITE_MUTEX_FAST 0 #define SQLITE_MUTEX_RECURSIVE 1 #define SQLITE_MUTEX_STATIC_MASTER 2 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ #define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */ #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */ #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ /* ** CAPI3REF: Low-Level Control Of Database Files {F11300} ** ** {F11301} The [sqlite3_file_control()] interface makes a direct call to the ** xFileControl method for the [sqlite3_io_methods] object associated ** with a particular database identified by the second argument. {F11302} The ** name of the database is the name assigned to the database by the ** <a href="lang_attach.html">ATTACH</a> SQL command that opened the ** database. {F11303} To control the main database file, use the name "main" ** or a NULL pointer. {F11304} The third and fourth parameters to this routine ** are passed directly through to the second and third parameters of ** the xFileControl method. {F11305} The return value of the xFileControl ** method becomes the return value of this routine. ** ** {F11306} If the second parameter (zDbName) does not match the name of any ** open database file, then SQLITE_ERROR is returned. {F11307} This error ** code is not remembered and will not be recalled by [sqlite3_errcode()] ** or [sqlite3_errmsg()]. {U11308} The underlying xFileControl method might ** also return SQLITE_ERROR. {U11309} There is no way to distinguish between ** an incorrect zDbName and an SQLITE_ERROR return from the underlying ** xFileControl method. {END} ** ** See also: [SQLITE_FCNTL_LOCKSTATE] */ int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); /* ** CAPI3REF: Testing Interface {F11400} ** ** The sqlite3_test_control() interface is used to read out internal ** state of SQLite and to inject faults into SQLite for testing ** purposes. The first parameter a operation code that determines ** the number, meaning, and operation of all subsequent parameters. ** ** This interface is not for use by applications. It exists solely ** for verifying the correct operation of the SQLite library. Depending ** on how the SQLite library is compiled, this interface might not exist. ** ** The details of the operation codes, their meanings, the parameters ** they take, and what they do are all subject to change without notice. ** Unlike most of the SQLite API, this function is not guaranteed to ** operate consistently from one release to the next. */ int sqlite3_test_control(int op, ...); /* ** CAPI3REF: Testing Interface Operation Codes {F11410} ** ** These constants are the valid operation code parameters used ** as the first argument to [sqlite3_test_control()]. ** ** These parameters and their meansing are subject to change ** without notice. These values are for testing purposes only. ** Applications should not use any of these parameters or the ** [sqlite3_test_control()] interface. */ #define SQLITE_TESTCTRL_FAULT_CONFIG 1 #define SQLITE_TESTCTRL_FAULT_FAILURES 2 #define SQLITE_TESTCTRL_FAULT_BENIGN_FAILURES 3 #define SQLITE_TESTCTRL_FAULT_PENDING 4 /* ** Undo the hack that converts floating point types to integer for ** builds on processors without floating point support. */ #ifdef SQLITE_OMIT_FLOATING_POINT # undef double #endif #ifdef __cplusplus } /* End of the 'extern "C"' block */ #endif #endif