/* ** 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: sqlite3.h,v 1.30 2007/06/19 22:43:24 rmsimpson Exp $ */ #ifndef _SQLITE3_H_ #define _SQLITE3_H_ #include /* Needed for the definition of va_list */ /* ** Make sure we can call this stuff from C++. */ #ifdef __cplusplus extern "C" { #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 ** ** The version of the SQLite library is contained in the sqlite3.h ** header file in a #define named SQLITE_VERSION. The SQLITE_VERSION ** macro resolves to a string constant. ** ** The format of the version string is "X.Y.Z", where ** X is the major version number, Y is the minor version number and Z ** is the release number. The X.Y.Z might be followed by "alpha" or "beta". ** For example "3.1.1beta". ** ** The X value is always 3 in SQLite. The X value only changes when ** backwards compatibility is broken and we intend to never break ** backwards compatibility. The Y value only changes when ** there are major feature enhancements that are forwards compatible ** but not backwards compatible. The Z value is incremented with ** each release but resets back to 0 when Y is incremented. ** ** The SQLITE_VERSION_NUMBER is an integer with the value ** (X*1000000 + Y*1000 + Z). For example, for version "3.1.1beta", ** SQLITE_VERSION_NUMBER is set to 3001001. To detect if they are using ** version 3.1.1 or greater at compile time, programs may use the test ** (SQLITE_VERSION_NUMBER>=3001001). ** ** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()]. */ #define SQLITE_VERSION "3.4.0" #define SQLITE_VERSION_NUMBER 3004000 /* ** CAPI3REF: Run-Time Library Version Numbers ** ** These routines return values equivalent to the header constants ** [SQLITE_VERSION] and [SQLITE_VERSION_NUMBER]. The values returned ** by this routines should only be different from the header values ** if you compile your program using an sqlite3.h header from a ** different version of SQLite that the version of the library you ** link against. ** ** The sqlite3_version[] string constant contains the text of the ** [SQLITE_VERSION] string. The sqlite3_libversion() function returns ** a poiner to the sqlite3_version[] string constant. The function ** is provided for DLL users who can only access functions and not ** constants within the DLL. */ extern const char sqlite3_version[]; const char *sqlite3_libversion(void); int sqlite3_libversion_number(void); /* ** CAPI3REF: Database Connection Handle ** ** 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] interface is its constructor ** 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 ** ** Some compilers do not support the "long long" datatype. So we have ** to do compiler-specific typedefs for 64-bit signed and unsigned integers. ** ** Many SQLite interface functions require a 64-bit integer arguments. ** Those interfaces are declared using this typedef. */ #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 /* ** If compiling for a processor that lacks floating point support, ** substitute integer for floating-point */ #ifdef SQLITE_OMIT_FLOATING_POINT # define double sqlite_int64 #endif /* ** CAPI3REF: Closing A Database Connection ** ** Call this function with a pointer to a structure that was previously ** returned from [sqlite3_open()] and the corresponding database will by ** closed. ** ** All SQL statements prepared using [sqlite3_prepare_v2()] or ** [sqlite3_prepare16_v2()] must be destroyed using [sqlite3_finalize()] ** before this routine is called. Otherwise, SQLITE_BUSY is returned and the ** database connection remains open. */ 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 ** ** This interface is used to do a one-time evaluatation of zero ** or more SQL statements. UTF-8 text of the SQL statements to ** be evaluted is passed in as the second parameter. The statements ** are prepared one by one using [sqlite3_prepare()], evaluated ** using [sqlite3_step()], then destroyed using [sqlite3_finalize()]. ** ** If one or more of the SQL statements are queries, then ** the callback function specified by the 3rd parameter is ** invoked once for each row of the query result. This callback ** should normally return 0. If the callback returns a non-zero ** value then the query is aborted, all subsequent SQL statements ** are skipped and the sqlite3_exec() function returns the SQLITE_ABORT. ** ** The 4th parameter to this interface is an arbitrary pointer that is ** passed through to the callback function as its first parameter. ** ** The 2nd parameter to the callback function is the number of ** columns in the query result. The 3rd parameter to the callback ** is an array of strings holding the values for each column ** as extracted using [sqlite3_column_text()]. ** The 4th parameter to the callback is an array of strings ** obtained using [sqlite3_column_name()] and holding ** the names of each column. ** ** The callback function may be NULL, even for queries. A NULL ** callback is not an error. It just means that no callback ** will be invoked. ** ** If an error occurs while parsing or evaluating the SQL (but ** not while executing the callback) then an appropriate error ** message is written into memory obtained from [sqlite3_malloc()] and ** *errmsg is made to point to that message. The calling function ** is responsible for freeing the memory that holds the error ** message. Use [sqlite3_free()] for this. If errmsg==NULL, ** then no error message is ever written. ** ** The return value is is SQLITE_OK if there are no errors and ** some other [SQLITE_OK | return code] if there is an error. ** The particular return value depends on the type of error. ** */ 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 ** KEYWORDS: SQLITE_OK ** ** Many SQLite functions return an integer result code from the set shown ** above in order to indicates success or failure. ** ** The result codes above are the only ones returned by SQLite in its ** default configuration. However, the [sqlite3_extended_result_codes()] ** API can be used to set a database connectoin to return more detailed ** result codes. ** ** 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 /* NOT USED. 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 contraint 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 ** ** In its default configuration, SQLite API routines return one of 26 integer ** result codes described at 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 users 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 above. ** We 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 symbolic name for an extended result code always contains a related ** primary result code as a prefix. Primary result codes contain a single ** "_" character. Extended result codes contain two or more "_" characters. ** The numeric value of an extended result code can be converted to its ** corresponding primary result code by masking off the lower 8 bytes. ** ** The SQLITE_OK result code will never be extended. It will always ** be exactly zero. */ #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)) /* ** CAPI3REF: Enable Or Disable Extended Result Codes ** ** This routine enables or disables the ** [SQLITE_IOERR_READ | extended result codes] feature. ** By default, SQLite API routines return one of only 26 integer ** [SQLITE_OK | result codes]. When extended result codes ** are enabled by this routine, the repetoire of result codes can be ** much larger and can (hopefully) provide more detailed information ** about the cause of an error. ** ** The second argument is a boolean value that turns extended result ** codes on and off. Extended result codes are off by default for ** backwards compatibility with older versions of SQLite. */ int sqlite3_extended_result_codes(sqlite3*, int onoff); /* ** CAPI3REF: Last Insert Rowid ** ** 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_. If the table has a column of ** type INTEGER PRIMARY KEY then that column is another an alias for the ** rowid. ** ** This routine returns the rowid of the most recent INSERT into ** the database from the database connection given in the first ** argument. If no 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. */ sqlite_int64 sqlite3_last_insert_rowid(sqlite3*); /* ** CAPI3REF: Count The Number Of Rows Modified ** ** This function returns the number of database rows that were changed ** (or inserted or deleted) by the most recent SQL statement. 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. ** ** 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 trigger. ** ** All changes are counted, even if they were later undone by a ** ROLLBACK or ABORT. Except, changes associated with creating and ** dropping tables are not counted. ** ** If a callback invokes [sqlite3_exec()] or [sqlite3_step()] recursively, ** then the changes in the inner, recursive call are counted together ** with the changes in the outer call. ** ** 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 form 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. */ int sqlite3_changes(sqlite3*); /* ** CAPI3REF: Total Number Of Rows Modified *** ** This function returns the number of database rows that have been ** modified by INSERT, UPDATE or DELETE statements since the database handle ** was opened. This includes UPDATE, INSERT and DELETE statements executed ** as part of trigger programs. All changes are counted as soon as the ** statement that makes them is completed (when the statement handle is ** passed to [sqlite3_reset()] or [sqlite_finalise()]). ** ** See also the [sqlite3_change()] interface. ** ** 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 form 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. */ int sqlite3_total_changes(sqlite3*); /* ** CAPI3REF: Interrupt A Long-Running Query ** ** 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. ** ** The SQL operation that is interrupted will return [SQLITE_INTERRUPT]. ** If an interrupted operation was an update that is inside an ** explicit transaction, then the entire transaction will be rolled ** back automatically. */ void sqlite3_interrupt(sqlite3*); /* ** CAPI3REF: Determine If An SQL Statement Is Complete ** ** These functions return true if the given input string comprises ** one or more complete SQL statements. For the sqlite3_complete() call, ** the parameter must be a nul-terminated UTF-8 string. For ** sqlite3_complete16(), a nul-terminated machine byte order UTF-16 string ** is required. ** ** These routines are useful for command-line input to determine if the ** currently entered text forms one or more complete SQL statements or ** if additional input is needed before sending the statements into ** SQLite for parsing. The algorithm is simple. If the ** last token other than spaces and comments is a semicolon, then return ** true. Actually, the algorithm is a little more complicated than that ** in order to deal with triggers, but the basic idea is the same: the ** statement is not complete unless it ends in a semicolon. */ int sqlite3_complete(const char *sql); int sqlite3_complete16(const void *sql); /* ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors ** ** 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 sometimes [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 return [SQLITE_BUSY] instead. ** 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 ** ** CorruptionFollowingBusyError wiki page for a discussion of why ** this is important. ** ** Sqlite is re-entrant, so the busy handler may start a new query. ** (It is not clear why anyone would every want to do this, but it ** is allowed, in theory.) But the busy handler may not close the ** database. Closing the database from a busy handler will delete ** data structures out from under the executing query and will ** probably result in a segmentation fault or other runtime error. ** ** 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. */ int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); /* ** CAPI3REF: Set A Busy Timeout ** ** This routine sets a 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. 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. */ int sqlite3_busy_timeout(sqlite3*, int ms); /* ** CAPI3REF: Convenience Routines For Running Queries ** ** This next routine is a convenience wrapper around [sqlite3_exec()]. ** Instead of invoking a user-supplied callback for each row of the ** result, this routine remembers each row of the result in memory ** obtained from [sqlite3_malloc()], then returns all of the result after the ** query has finished. ** ** As an example, suppose the query result where this table: ** ** 
**        Name        | Age
**        -----------------------
**        Alice       | 43
**        Bob         | 28
**        Cindy       | 21
**
** ** If the 3rd argument were &azResult then after the function returns ** azResult will contain the following data: ** ** 
**        azResult[0] = "Name";
**        azResult[1] = "Age";
**        azResult[2] = "Alice";
**        azResult[3] = "43";
**        azResult[4] = "Bob";
**        azResult[5] = "28";
**        azResult[6] = "Cindy";
**        azResult[7] = "21";
**
** ** Notice that there is an extra row of data containing the column ** headers. But the *nrow return value is still 3. *ncolumn is ** set to 2. In general, the number of values inserted into azResult ** will be ((*nrow) + 1)*(*ncolumn). ** ** After the calling function has finished using the result, it should ** pass the result data pointer to sqlite3_free_table() in order to ** release the memory that was malloc-ed. Because of the way the ** [sqlite3_malloc()] happens, 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 return value of this routine is the same as from [sqlite3_exec()]. */ int sqlite3_get_table( sqlite3*, /* An open database */ const char *sql, /* SQL to be executed */ char ***resultp, /* Result written to a char *[] that this points to */ 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 ** ** 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 [sqlite_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" and "%Q" 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: ** ** 
**  char *zText = "It's a happy day!";
**
** ** One can use this text in an SQL statement as follows: ** ** 
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
**
** ** Because the %q format string is used, the '\'' character in zText ** is escaped and the SQL generated is as follows: ** ** 
**  INSERT INTO table1 VALUES('It''s a happy day!')
**
** ** This is correct. Had we used %s instead of %q, the generated SQL ** would have looked like this: ** ** 
**  INSERT INTO table1 VALUES('It's a happy day!');
**
** ** 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. So, for example, one could say: ** ** 
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
**
** ** The code above will render a correct SQL statement in the zSQL ** variable even if the zText variable is a NULL pointer. */ char *sqlite3_mprintf(const char*,...); char *sqlite3_vmprintf(const char*, va_list); char *sqlite3_snprintf(int,char*,const char*, ...); /* ** CAPI3REF: Memory Allocation Functions ** ** SQLite uses its own memory allocator. On some installations, this ** memory allocator is identical to the standard malloc()/realloc()/free() ** and can be used interchangable. On others, the implementations are ** different. For maximum portability, it is best not to mix calls ** to the standard malloc/realloc/free with the sqlite versions. */ void *sqlite3_malloc(int); void *sqlite3_realloc(void*, int); void sqlite3_free(void*); /* ** CAPI3REF: Compile-Time Authorization Callbacks *** ** This routine registers a authorizer callback with the SQLite library. ** 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. ** ** Depending on the action, the [SQLITE_IGNORE] and [SQLITE_DENY] return ** codes might mean something different or they might mean the same ** thing. If the action is, for example, to perform a delete opertion, ** then [SQLITE_IGNORE] and [SQLITE_DENY] both cause the statement compilation ** to fail with an error. But if the action is to read a specific column ** from a specific table, then [SQLITE_DENY] will cause the entire ** statement to fail but [SQLITE_IGNORE] will cause a NULL value to be ** read instead of the actual column value. ** ** 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 available action codes are ** [SQLITE_COPY | documented separately]. The third through sixth ** parameters to the callback are 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. A NULL authorizer means that no authorization ** callback is invoked. The default authorizer is NULL. ** ** Note that the authorizer callback is invoked only during ** [sqlite3_prepare()] or its variants. Authorization is not ** performed during statement evaluation in [sqlite3_step()]. */ int sqlite3_set_authorizer( sqlite3*, int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), void *pUserData ); /* ** CAPI3REF: Authorizer Return Codes ** ** 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 ** ** 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. */ /******************************************* 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 ** ** 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 the first [sqlite3_step()] for the evaluation of an SQL statement. ** The callback function registered by sqlite3_profile() is invoked ** as each SQL statement finishes and includes ** information on how long that statement ran. ** ** The sqlite3_profile() API is currently considered experimental and ** is subject to change. */ void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*); void *sqlite3_profile(sqlite3*, void(*xProfile)(void*,const char*,sqlite_uint64), void*); /* ** CAPI3REF: Query Progress Callbacks ** ** 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. ** ** The progress callback is invoked once for every N virtual machine opcodes, ** where N is the second argument to this function. The progress callback ** itself is identified by the third argument to this function. The fourth ** argument to this function is a void pointer passed to the progress callback ** function each time it is invoked. ** ** If a call to [sqlite3_exec()], [sqlite3_step()], or [sqlite3_get_table()] ** results in fewer than N opcodes being executed, then the progress ** callback is never invoked. ** ** Only a single progress callback function may be registered for each ** open database connection. Every call to sqlite3_progress_handler() ** overwrites the results of the previous call. ** To remove the progress callback altogether, pass NULL as the third ** argument to this function. ** ** If the progress callback returns a result other than 0, then the current ** query is immediately terminated and any database changes rolled back. ** The containing [sqlite3_exec()], [sqlite3_step()], or ** [sqlite3_get_table()] call returns SQLITE_INTERRUPT. This feature ** can be used, for example, to implement the "Cancel" button on a ** progress dialog box in a GUI. */ void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); /* ** CAPI3REF: Opening A New Database Connection ** ** Open the sqlite database file "filename". The "filename" is UTF-8 ** encoded for sqlite3_open() and UTF-16 encoded in the native byte order ** for sqlite3_open16(). An [sqlite3*] handle is returned in *ppDb, even ** if an error occurs. If the database is opened (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. ** ** If the database file does not exist, then a new database will be created ** as needed. The default encoding for the database will be UTF-8 if ** sqlite3_open() is called and UTF-16 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. ** ** Note to windows users: The encoding used for the filename argument ** of sqlite3_open() 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(). */ 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 */ ); /* ** CAPI3REF: Error Codes And Messages ** ** 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-langauge ** text that describes the error, as either UTF8 or UTF16 respectively. ** Memory to hold the error message string is managed internally. The ** string may be overwritten or deallocated by subsequent calls to SQLite ** interface functions. ** ** Calls to many sqlite3_* functions set the error code and string returned ** by [sqlite3_errcode()], [sqlite3_errmsg()], and [sqlite3_errmsg16()] ** (overwriting the previous values). Note that calls to [sqlite3_errcode()], ** [sqlite3_errmsg()], and [sqlite3_errmsg16()] themselves do not affect the ** results of future invocations. Calls to API routines that do not return ** an error code (examples: [sqlite3_data_count()] or [sqlite3_mprintf()]) do ** not change the error code returned by this routine. ** ** Assuming no other intervening sqlite3_* API calls are made, the error ** code returned by this function is associated with the same error as ** the strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()]. */ int sqlite3_errcode(sqlite3 *db); const char *sqlite3_errmsg(sqlite3*); const void *sqlite3_errmsg16(sqlite3*); /* ** CAPI3REF: SQL Statement Object ** ** Instance of this object represent single SQL statements. This ** 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: ** **
    **
  1. Create the object using [sqlite3_prepare_v2()] or a related ** function. **
  2. Bind values to host parameters using ** [sqlite3_bind_blob | sqlite3_bind_* interfaces]. **
  3. Run the SQL by calling [sqlite3_step()] one or more times. **
  4. Reset the statement using [sqlite3_reset()] then go back ** to step 2. Do this zero or more times. **
  5. Destroy the object using [sqlite3_finalize()]. **
** ** Refer to documentation on individual methods above for additional ** information. */ typedef struct sqlite3_stmt sqlite3_stmt; /* ** CAPI3REF: Compiling An SQL Statement ** ** 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 [sqlite3 | SQLite database handle] ** obtained from a prior call to [sqlite3_open()] 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. If the next argument, "nBytes", is less ** than zero, then zSql is read up to the first zero terminator. If ** "nBytes" is not less than zero, then it is the length of the string zSql ** in bytes (not characters). ** ** *pzTail is made to point to the first byte past the end of the first ** SQL statement in zSql. This routine only compiles the first statement ** in zSql, so *pzTail is left pointing to what remains uncompiled. ** ** *ppStmt is left pointing to a compiled ** [sqlite3_stmt | SQL statement structure] that can be ** executed using [sqlite3_step()]. Or if there is an error, *ppStmt may be ** set to NULL. If the input text contained no SQL (if the input is and ** empty string or a comment) then *ppStmt is set to NULL. 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 ** [SQLITE_ERROR | 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. This causes the [sqlite3_step()] interface to ** behave a differently in two ways: ** **
    **
  1. ** 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. **
    2. ** **
  2. ** When an error occurs, ** [sqlite3_step()] will return one of the detailed ** [SQLITE_ERROR | result codes] or ** [SQLITE_IOERR_READ | extended result codes] such as directly. ** 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. **
    3. **
*/ int sqlite3_prepare( sqlite3 *db, /* Database handle */ const char *zSql, /* SQL statement, UTF-8 encoded */ int nBytes, /* 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 nBytes, /* 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 nBytes, /* 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 nBytes, /* Length of zSql in bytes. */ sqlite3_stmt **ppStmt, /* OUT: Statement handle */ const void **pzTail /* OUT: Pointer to unused portion of zSql */ ); /* ** CAPI3REF: Dynamically Typed Value Object ** ** SQLite uses dynamic typing for the values it stores. Values can ** be integers, floating point values, strings, BLOBs, or NULL. When ** passing around values internally, each value is represented as ** an instance of the sqlite3_value object. */ typedef struct Mem sqlite3_value; /* ** CAPI3REF: SQL Function Context Object ** ** The context in which an SQL function executes is stored in an ** sqlite3_context object. A pointer to such an object is the ** first parameter to user-defined SQL functions. */ typedef struct sqlite3_context sqlite3_context; /* ** CAPI3REF: Binding Values To Prepared Statements ** ** In the SQL strings input to [sqlite3_prepare_v2()] and its variants, ** one or more literals can be replace by a parameter in one of these ** forms: ** ** ** ** In the parameter forms shown above NNN is an integer literal, ** AAA is an alphanumeric identifier and VVV is a variable name according ** to the syntax rules of the TCL programming language. ** The values of these parameters (also called "host parameter names") ** 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" ** parametes is the value of NNN. ** The NNN value must be between 1 and the compile-time ** parameter SQLITE_MAX_VARIABLE_NUMBER (default value: 999). ** See limits.html for additional information. ** ** 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 bytes in the ** string, 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 ** text after SQLite has finished with it. If the fifth argument is the ** special value [SQLITE_STATIC], then the library 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. ** ** 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] is returned if these routines are called on a virtual ** machine that is the wrong state or which has already been finalized. */ 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, sqlite_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 Host Parameters ** ** Return the largest host parameter index in the precompiled statement given ** as the argument. When the host parameters are of the forms like ":AAA" ** or "?", then they are assigned sequential increasing numbers beginning ** with one, so the value returned is the number of parameters. However ** if the same host parameter name is used multiple times, each occurrance ** is given the same number, so the value returned in that case is the number ** of unique host parameter names. If host parameters of the form "?NNN" ** are used (where NNN is an integer) then there might be gaps in the ** numbering and the value returned by this interface is the index of the ** host parameter with the largest index value. */ int sqlite3_bind_parameter_count(sqlite3_stmt*); /* ** CAPI3REF: Name Of A Host Parameter ** ** This routine returns a pointer to the name of the n-th parameter in a ** [sqlite3_stmt | prepared statement]. ** Host parameters of the form ":AAA" or "@AAA" or "$VVV" have a name ** which is the string ":AAA" or "@AAA" or "$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 bound 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()]. */ const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); /* ** CAPI3REF: Index Of A Parameter With A Given Name ** ** This routine returns the index of a host parameter with the given name. ** The name must match exactly. If no parameter with the given name is ** found, return 0. Parameter names must be UTF8. */ int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); /* ** CAPI3REF: Reset All Bindings On A Prepared Statement ** ** Contrary to the intuition of many, [sqlite3_reset()] does not ** reset the [sqlite3_bind_blob | bindings] on a ** [sqlite3_stmt | prepared statement]. Use this routine to ** reset all host parameters to NULL. */ int sqlite3_clear_bindings(sqlite3_stmt*); /* ** CAPI3REF: Number Of Columns In A Result Set ** ** Return the number of columns in the result set returned by the ** [sqlite3_stmt | compiled SQL statement]. This routine returns 0 ** if pStmt is an SQL statement that does not return data (for ** example an UPDATE). */ int sqlite3_column_count(sqlite3_stmt *pStmt); /* ** CAPI3REF: Column Names In A Result Set ** ** 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 UTF8 string and sqlite3_column_name16() ** returns a pointer to a UTF16 string. The first parameter is the ** [sqlite_stmt | 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 ** [sqlite_stmt | prepared statement] is destroyed by [sqlite3_finalize()] ** or until the next call sqlite3_column_name() or sqlite3_column_name16() ** on the same column. */ 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 ** ** 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 returned string is valid until ** the [sqlite3_stmt | prepared statement] is destroyed using ** [sqlite3_finalize()] or until the same information is requested ** again about the same column. ** ** The first argument to the following calls is a ** [sqlite3_stmt | compiled SQL 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. 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. ** ** These APIs are only available if the library was compiled with the ** SQLITE_ENABLE_COLUMN_METADATA preprocessor symbol defined. */ 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 ** ** The first parameter is a [sqlite3_stmt | compiled SQL 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. 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. */ const char *sqlite3_column_decltype(sqlite3_stmt *, int i); const void *sqlite3_column_decltype16(sqlite3_stmt*,int); /* ** CAPI3REF: Evaluate An SQL Statement ** ** After an [sqlite3_stmt | SQL 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 ** [sqlite_stmt | 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 [sqlite_stmt | 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. ** ** Goofy Interface Alert: ** 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 ** [SQLITE_ERROR | result 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 [SQLITE_ERROR | result codes] are returned directly ** by sqlite3_step(). The use of the "v2" interface is recommended. */ int sqlite3_step(sqlite3_stmt*); /* ** CAPI3REF: ** ** Return the number of values in the current row of the result set. ** ** After a call to [sqlite3_step()] that returns [SQLITE_ROW], this routine ** will return the same value as the [sqlite3_column_count()] function. ** After [sqlite3_step()] has returned an [SQLITE_DONE], [SQLITE_BUSY], or ** a [SQLITE_ERROR | error code], or before [sqlite3_step()] has been ** called on the [sqlite_stmt | prepared statement] for the first time, ** this routine returns zero. */ int sqlite3_data_count(sqlite3_stmt *pStmt); /* ** CAPI3REF: Fundamental Datatypes ** ** Every value in SQLite has one of five fundamental datatypes: ** ** ** ** 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 ** ** These routines return information about the information ** in a single column of the current result row of a query. In every ** case the first argument is a pointer to the ** [sqlite3_stmt | SQL statement] that is being ** evaluate (the [sqlite_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 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. ** ** 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. ** *** The sqlite3_column_nm ** ** 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. ** ** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes() ** but leaves the result in UTF-16 instead of UTF-8. ** The zero terminator is not included in this count. ** ** 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: ** **
** **
Internal Requested **
Type Type Conversion ** **
NULL INTEGER Result is 0 **
NULL FLOAT Result is 0.0 **
NULL TEXT Result is NULL pointer **
NULL BLOB Result is NULL pointer **
INTEGER FLOAT Convert from integer to float **
INTEGER TEXT ASCII rendering of the integer **
INTEGER BLOB Same as for INTEGER->TEXT **
FLOAT INTEGER Convert from float to integer **
FLOAT TEXT ASCII rendering of the float **
FLOAT BLOB Same as FLOAT->TEXT **
TEXT INTEGER Use atoi() **
TEXT FLOAT Use atof() **
TEXT BLOB No change **
BLOB INTEGER Convert to TEXT then use atoi() **
BLOB FLOAT Convert to TEXT then use atof() **
BLOB TEXT Add a zero terminator if needed **
**
** ** 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: ** ** ** ** 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: ** ** ** ** 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(). */ 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); sqlite_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 ** ** The sqlite3_finalize() function is called to delete a ** [sqlite3_stmt | compiled SQL 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 ** [SQLITE_ERROR | error code] or [SQLITE_IOERR_READ | extended error code] ** is returned. ** ** This routine can be called at any point during the execution of the ** [sqlite3_stmt | virtual machine]. 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 ** [SQLITE_ERROR | result code] returned will be [SQLITE_ABORT]. */ int sqlite3_finalize(sqlite3_stmt *pStmt); /* ** CAPI3REF: Reset A Prepared Statement Object ** ** The sqlite3_reset() function is called to reset a ** [sqlite_stmt | compiled SQL statement] object. ** back to it's 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. */ int sqlite3_reset(sqlite3_stmt *pStmt); /* ** CAPI3REF: Create Or Redefine SQL Functions ** ** The following two functions 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 argument is the [sqlite3 | database handle] that holds the ** SQL function or aggregate is to be added or redefined. If a single ** program uses more than one database handle internally, then SQL ** functions or aggregates must be added individually to each database ** handle with which they will be used. ** ** 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 sqlite_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 ** [sqlite_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. */ int sqlite3_create_function( sqlite3 *, const char *zFunctionName, int nArg, int eTextRep, void*, void (*xFunc)(sqlite3_context*,int,sqlite3_value**), void (*xStep)(sqlite3_context*,int,sqlite3_value**), void (*xFinal)(sqlite3_context*) ); int sqlite3_create_function16( sqlite3*, const void *zFunctionName, int nArg, int eTextRep, void*, void (*xFunc)(sqlite3_context*,int,sqlite3_value**), void (*xStep)(sqlite3_context*,int,sqlite3_value**), void (*xFinal)(sqlite3_context*) ); /* ** CAPI3REF: Text Encodings ** ** 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); /* ** CAPI3REF: Obtaining SQL Function Parameter Values ** ** 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 ** [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 just like the corresponding ** [sqlite3_column_blob | sqlite3_column_* routines] except that ** these routines take a single [sqlite3_value*] 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 order ** words if the value is original a string that looks like a number) ** then it 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()], [sqlite_value_text()], ** or [sqlite3_value_text16()]. */ 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*); sqlite_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 ** ** The implementation of aggregate SQL functions use this routine to allocate ** a structure for storing their state. The first time this routine ** is called for a particular aggregate, a new structure of size nBytes ** is allocated, zeroed, and returned. On subsequent calls (for the ** same aggregate instance) the same buffer is returned. The implementation ** of the aggregate can use the returned buffer to accumulate data. ** ** The buffer allocated is freed automatically by SQLite whan 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. */ void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); /* ** CAPI3REF: User Data For Functions ** ** The pUserData parameter to the [sqlite3_create_function()] ** and [sqlite3_create_function16()] routines ** used to register user functions is available to ** the implementation of the function using this call. */ void *sqlite3_user_data(sqlite3_context*); /* ** CAPI3REF: Function Auxiliary Data ** ** 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 with the Nth argument value to the current SQL function ** call, where N is the second parameter. If no meta-data has been set for ** that value, then a NULL pointer is returned. ** ** The sqlite3_set_auxdata() is used to associate meta-data with an SQL ** function argument. The third parameter is a pointer to the meta-data ** to be associated with the Nth user function argument value. The fourth ** parameter specifies a destructor that will be called on the meta- ** data pointer to release it when it is no longer required. If the ** destructor is NULL, it is not invoked. ** ** In practice, meta-data is preserved between function calls for ** expressions that are constant at compile time. This includes literal ** values and SQL variables. */ void *sqlite3_get_auxdata(sqlite3_context*, int); void sqlite3_set_auxdata(sqlite3_context*, int, void*, void (*)(void*)); /* ** CAPI3REF: Constants Defining Special Destructor Behavior ** ** 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 ** ** 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_error() and sqlite3_result_error16() functions ** cause the implemented SQL function to throw an exception. The ** parameter to sqlite3_result_error() or sqlite3_result_error16() ** is the text of an error message. ** ** The sqlite3_result_toobig() cause the function implementation ** to throw and error indicating that a string or BLOB is to long ** to represent. */ 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_int(sqlite3_context*, int); void sqlite3_result_int64(sqlite3_context*, sqlite_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 ** ** 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 must 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. ** ** 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 user ** 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 user-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. The user 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()]. ** ** The sqlite3_create_collation_v2() interface is experimental and ** subject to change in future releases. The other collation creation ** functions are stable. */ 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 ** ** 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. 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()]. */ 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 ** ** This function causes the current thread to suspect execution ** 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. */ int sqlite3_sleep(int); /* ** CAPI3REF: Name Of The Folder Holding Temporary Files ** ** 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. ** ** Once [sqlite3_open()] has been called, changing this variable will ** invalidate the current temporary database, if any. Generally speaking, ** it is not safe to invoke this routine after [sqlite3_open()] has ** been called. */ extern char *sqlite3_temp_directory; /* ** CAPI3REF: Test To See If The Databse Is In Auto-Commit Mode ** ** Test to see whether or not the database connection is in autocommit ** mode. Return TRUE if it is and FALSE if not. Autocommit mode is on ** by default. Autocommit is disabled by a BEGIN statement and reenabled ** by the next COMMIT or ROLLBACK. */ int sqlite3_get_autocommit(sqlite3*); /* ** CAPI3REF: Find The Database Handle Associated With A Prepared Statement ** ** Return the [sqlite3*] database handle to which a ** [sqlite3_stmt | prepared statement] belongs. ** This 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. */ sqlite3 *sqlite3_db_handle(sqlite3_stmt*); /* ** CAPI3REF: Commit And Rollback Notification Callbacks ** ** These routines ** register callback functions to be invoked whenever a transaction ** is committed or rolled back. 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 ** callback is not invoked if a transaction is automatically rolled ** back because the database connection is closed. ** ** These are experimental interfaces and are subject to change. */ void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); /* ** CAPI3REF: Data Change Notification Callbacks ** ** Register 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. */ void *sqlite3_update_hook( sqlite3*, void(*)(void *,int ,char const *,char const *,sqlite_int64), void* ); /* ** CAPI3REF: Enable Or Disable Shared Pager Cache ** ** 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 on a thread-by-thread basis. ** Each call to this routine enables or disables cache sharing only for ** connections created in the same thread in which this routine is called. ** There is no mechanism for sharing cache between database connections ** running in different threads. ** ** Sharing must be disabled prior to shutting down a thread or else ** the thread will leak memory. Call this routine with an argument of ** 0 to turn off sharing. Or use the sqlite3_thread_cleanup() API. ** ** This routine must not be called when any database connections ** are active in the current thread. Enabling or disabling shared ** cache while there are active database connections will result ** in memory corruption. ** ** When the shared cache is enabled, the ** following routines must always be called from the same thread: ** [sqlite3_open()], [sqlite3_prepare_v2()], [sqlite3_step()], ** [sqlite3_reset()], [sqlite3_finalize()], and [sqlite3_close()]. ** This is due to the fact that the shared cache makes use of ** thread-specific storage so that it will be available for sharing ** with other connections. ** ** 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 [SQLITE_ERROR | error code] ** is returned otherwise. ** ** Shared cache is disabled by default for backward compatibility. */ int sqlite3_enable_shared_cache(int); /* ** CAPI3REF: Attempt To Free Heap Memory ** ** Attempt to free N bytes of heap memory by deallocating non-essential ** memory allocations held by the database library (example: memory ** used to cache database pages to improve performance). ** ** This function is not a part of standard builds. It is only created ** if SQLite is compiled with the SQLITE_ENABLE_MEMORY_MANAGEMENT macro. */ int sqlite3_release_memory(int); /* ** CAPI3REF: Impose A Limit On Heap Size ** ** Place a "soft" limit on the amount of heap memory that may be allocated by ** SQLite within the current thread. If an internal allocation is requested ** that would exceed the specified 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. ** ** Prior to shutting down a thread sqlite3_soft_heap_limit() must be set to ** zero (the default) or else the thread will leak memory. Alternatively, use ** the [sqlite3_thread_cleanup()] API. ** ** 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 exhaused. ** The default value for the soft heap limit is zero. ** ** SQLite makes a best effort to honor the soft heap limit. But if it ** is unable to reduce memory usage below the soft limit, execution will ** continue without error or notification. This is why the limit is ** called a "soft" limit. It is advisory only. ** ** This function is only available if the library was compiled with the ** SQLITE_ENABLE_MEMORY_MANAGEMENT option set. ** memory-management has been enabled. */ void sqlite3_soft_heap_limit(int); /* ** CAPI3REF: Clean Up Thread Local Storage ** ** This routine makes sure that all thread-local storage has been ** deallocated for the current thread. ** ** This routine is not technically necessary. All thread-local storage ** will be automatically deallocated once memory-management and ** shared-cache are disabled and the soft heap limit has been set ** to zero. This routine is provided as a convenience for users who ** want to make absolutely sure they have not forgotten something ** prior to killing off a thread. */ void sqlite3_thread_cleanup(void); /* ** CAPI3REF: Extract Metadata About A Column Of A Table ** ** 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. ** ** 
** 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
**
** ** ** 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: ** ** 
**     data type: "INTEGER"
**     collation sequence: "BINARY"
**     not null: 0
**     primary key: 1
**     auto increment: 0
**
** ** 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 colums is auto-increment */ ); /* ** CAPI3REF: Load An Extension ** ** Attempt to load an SQLite extension library contained in the file ** zFile. The entry point is zProc. zProc may be 0 in which case the ** name of the entry point defaults to "sqlite3_extension_init". ** ** Return [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. ** ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with ** error message text. The calling function should free this memory ** by calling [sqlite3_free()]. ** ** 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 ** ** 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. It is off by default. See ticket #1863. ** ** Call this routine with onoff==1 to turn extension loading on ** and call it with onoff==0 to turn it back off again. */ int sqlite3_enable_load_extension(sqlite3 *db, int onoff); /* ** CAPI3REF: Make Arrangements To Automatically Load An Extension ** ** Register an extension entry point that is automatically invoked ** whenever a new database connection is opened using ** [sqlite3_open()] or [sqlite3_open16()]. ** ** 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. ** ** Duplicate extensions are detected so calling this routine multiple ** times with the same extension is harmless. ** ** This routine stores a pointer to the extension in an array ** that is obtained from malloc(). If you run a memory leak ** checker on your program and it reports a leak because of this ** array, then invoke [sqlite3_automatic_extension_reset()] prior ** to shutdown to free the memory. ** ** Automatic extensions apply across all threads. ** ** 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 ** ** Disable all previously registered automatic extensions. This ** routine undoes the effect of all prior [sqlite3_automatic_extension()] ** calls. ** ** This call disabled automatic extensions in all threads. ** ** 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; /* ** 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*, sqlite_int64 *pRowid); int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite_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); }; /* ** 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 simplificatinos 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 */ const int nConstraint; /* Number of entries in aConstraint */ const 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 */ } *const aConstraint; /* Table of WHERE clause constraints */ const int nOrderBy; /* Number of terms in the ORDER BY clause */ const struct sqlite3_index_orderby { int iColumn; /* Column number */ unsigned char desc; /* True for DESC. False for ASC. */ } *const 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 */ } *const 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 /* ** 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 */ ); /* ** Every module implementation uses a subclass of the following structure ** to describe a particular instance of the module. Each subclass will ** be taylored 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 */ }; /* 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 */ }; /* ** 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); /* ** 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 stablizes, 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 ** ** An instance of the following opaque structure is used to ** represent an blob-handle. A blob-handle is 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 [sqltie3_blob_size()] interface returns the size of the ** blob in bytes. */ typedef struct sqlite3_blob sqlite3_blob; /* ** CAPI3REF: Open A BLOB For Incremental I/O ** ** Open a handle to the blob located in row iRow,, column zColumn, ** table zTable in database zDb. i.e. the same blob that would ** be selected by: ** ** 
**     SELECT zColumn FROM zDb.zTable WHERE rowid = iRow;
**
** ** 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()]. */ int sqlite3_blob_open( sqlite3*, const char *zDb, const char *zTable, const char *zColumn, sqlite_int64 iRow, int flags, sqlite3_blob **ppBlob ); /* ** CAPI3REF: Close A BLOB Handle ** ** Close an open [sqlite3_blob | blob handle]. */ int sqlite3_blob_close(sqlite3_blob *); /* ** CAPI3REF: Return The Size Of An Open BLOB ** ** Return the size in bytes of the blob accessible via the open ** [sqlite3_blob | blob-handle] passed as an argument. */ int sqlite3_blob_bytes(sqlite3_blob *); /* ** CAPI3REF: Read Data From A BLOB Incrementally ** ** 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. ** ** On success, SQLITE_OK is returned. Otherwise, an ** [SQLITE_ERROR | SQLite error code] or an ** [SQLITE_IOERR_READ | extended error code] is returned. */ int sqlite3_blob_read(sqlite3_blob *, void *z, int n, int iOffset); /* ** CAPI3REF: Write Data Into A BLOB Incrementally ** ** 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. ** ** On success, SQLITE_OK is returned. Otherwise, an ** [SQLITE_ERROR | SQLite error code] or an ** [SQLITE_IOERR_READ | extended error code] is returned. */ int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); /* ** 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