sqlite3.h

**
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
** <dd>The maximum depth of recursion for triggers.</dd>)^
** </dl>
*/
#define SQLITE_LIMIT_LENGTH                    0
#define SQLITE_LIMIT_SQL_LENGTH                1
#define SQLITE_LIMIT_COLUMN                    2
#define SQLITE_LIMIT_EXPR_DEPTH                3
#define SQLITE_LIMIT_COMPOUND_SELECT           4
#define SQLITE_LIMIT_VDBE_OP                   5
#define SQLITE_LIMIT_FUNCTION_ARG              6
#define SQLITE_LIMIT_ATTACHED                  7
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
#define SQLITE_LIMIT_VARIABLE_NUMBER           9
#define SQLITE_LIMIT_TRIGGER_DEPTH            10

/*
** CAPI3REF: Compiling An SQL Statement
** KEYWORDS: {SQL statement compiler}
**
** 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 a [database connection] obtained from a
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
** [sqlite3_open16()].  The database connection must not have been closed.
**
** 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 use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
** use UTF-16.
**
** ^If the nByte argument is less than zero, then zSql is read up to the
** first zero terminator. ^If nByte is non-negative, then it is the maximum
** number of  bytes read from zSql.  ^When nByte is non-negative, the
** zSql string ends at either the first '\000' or '\u0000' character or
** the nByte-th byte, whichever comes first. If the caller knows
** that the supplied string is nul-terminated, then there is a small
** performance advantage to be gained by passing an nByte parameter that
** is equal to the number of bytes in the input string <i>including</i>
** the nul-terminator bytes as this saves SQLite from having to
** make a copy of the input string.
**
** ^If pzTail is not NULL then *pzTail is made to point to the first byte
** past the end of the first SQL statement in zSql.  These routines only
** compile the first statement in zSql, so *pzTail is left pointing to
** what remains uncompiled.
**
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
** to NULL.  ^If the input text contains no SQL (if the input is an 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.
** ppStmt may not be NULL.
**
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
** otherwise an [error code] is returned.
**
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
** recommended for all new programs. The two older interfaces are retained
** for backwards compatibility, but their use is discouraged.
** ^In the "v2" interfaces, the prepared statement
** that is returned (the [sqlite3_stmt] object) contains a copy of the
** original SQL text. This causes the [sqlite3_step()] interface to
** behave differently in three ways:
**
** <ol>
** <li>
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
** always used to do, [sqlite3_step()] will automatically recompile the SQL
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
** retries will occur before sqlite3_step() gives up and returns an error.
** </li>
**
** <li>
** ^When an error occurs, [sqlite3_step()] will return one of the detailed
** [error codes] or [extended error codes].  ^The legacy behavior was that
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
** and the application would have to make a second call to [sqlite3_reset()]
** in order to find the underlying cause of the problem. With the "v2" prepare
** interfaces, the underlying reason for the error is returned immediately.
** </li>
**
** <li>
** ^If the specific value bound to [parameter | host parameter] in the 
** WHERE clause might influence the choice of query plan for a statement,
** then the statement will be automatically recompiled, as if there had been 
** a schema change, on the first  [sqlite3_step()] call following any change
** to the [sqlite3_bind_text | bindings] of that [parameter]. 
** ^The specific value of WHERE-clause [parameter] might influence the 
** choice of query plan if the parameter is the left-hand side of a [LIKE]
** or [GLOB] operator or if the parameter is compared to an indexed column
** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
** the 
** </li>
** </ol>
*/
SQLITE_API int sqlite3_prepare(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare_v2(
  sqlite3 *db,            /* Database handle */
  const char *zSql,       /* SQL statement, UTF-8 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const char **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare16(
  sqlite3 *db,            /* Database handle */
  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);
SQLITE_API int sqlite3_prepare16_v2(
  sqlite3 *db,            /* Database handle */
  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);

/*
** CAPI3REF: Retrieving Statement SQL
**
** ^This interface can be used to retrieve a saved copy of the original
** SQL text used to create a [prepared statement] if that statement was
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
*/
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If An SQL Statement Writes The Database
**
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
** and only if the [prepared statement] X makes no direct changes to
** the content of the database file.
**
** Note that [application-defined SQL functions] or
** [virtual tables] might change the database indirectly as a side effect.  
** ^(For example, if an application defines a function "eval()" that 
** calls [sqlite3_exec()], then the following SQL statement would
** change the database file through side-effects:
**
** <blockquote><pre>
**    SELECT eval('DELETE FROM t1') FROM t2;
** </pre></blockquote>
**
** But because the [SELECT] statement does not change the database file
** directly, sqlite3_stmt_readonly() would still return true.)^
**
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
** since the statements themselves do not actually modify the database but
** rather they control the timing of when other statements modify the 
** database.  ^The [ATTACH] and [DETACH] statements also cause
** sqlite3_stmt_readonly() to return true since, while those statements
** change the configuration of a database connection, they do not make 
** changes to the content of the database files on disk.
*/
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Determine If A Prepared Statement Has Been Reset
**
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
** [prepared statement] S has been stepped at least once using 
** [sqlite3_step(S)] but has not run to completion and/or has not 
** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
** interface returns false if S is a NULL pointer.  If S is not a 
** NULL pointer and is not a pointer to a valid [prepared statement]
** object, then the behavior is undefined and probably undesirable.
**
** This interface can be used in combination [sqlite3_next_stmt()]
** to locate all prepared statements associated with a database 
** connection that are in need of being reset.  This can be used,
** for example, in diagnostic routines to search for prepared 
** statements that are holding a transaction open.
*/
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);

/*
** CAPI3REF: Dynamically Typed Value Object
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
**
** SQLite uses the sqlite3_value object to represent all values
** that can be stored in a database table. SQLite uses dynamic typing
** for the values it stores.  ^Values stored in sqlite3_value objects
** can be integers, floating point values, strings, BLOBs, or NULL.
**
** An sqlite3_value object may be either "protected" or "unprotected".
** Some interfaces require a protected sqlite3_value.  Other interfaces
** will accept either a protected or an unprotected sqlite3_value.
** Every interface that accepts sqlite3_value arguments specifies
** whether or not it requires a protected sqlite3_value.
**
** The terms "protected" and "unprotected" refer to whether or not
** a mutex is held.  An internal mutex is held for a protected
** sqlite3_value object but no mutex is held for an unprotected
** sqlite3_value object.  If SQLite is compiled to be single-threaded
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
** or if SQLite is run in one of reduced mutex modes 
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
** then there is no distinction between protected and unprotected
** sqlite3_value objects and they can be used interchangeably.  However,
** for maximum code portability it is recommended that applications
** still make the distinction between protected and unprotected
** sqlite3_value objects even when not strictly required.
**
** ^The sqlite3_value objects that are passed as parameters into the
** implementation of [application-defined SQL functions] are protected.
** ^The sqlite3_value object returned by
** [sqlite3_column_value()] is unprotected.
** Unprotected sqlite3_value objects may only be used with
** [sqlite3_result_value()] and [sqlite3_bind_value()].
** The [sqlite3_value_blob | sqlite3_value_type()] family of
** interfaces require protected sqlite3_value objects.
*/
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 an sqlite3_context object
** is always first parameter to [application-defined SQL functions].
** The application-defined SQL function implementation will pass this
** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
** [sqlite3_aggregate_context()], [sqlite3_user_data()],
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
** and/or [sqlite3_set_auxdata()].
*/
typedef struct sqlite3_context sqlite3_context;

/*
** CAPI3REF: Binding Values To Prepared Statements
** KEYWORDS: {host parameter} {host parameters} {host parameter name}
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
**
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
** literals may be replaced by a [parameter] that matches one of following
** templates:
**
** <ul>
** <li>  ?
** <li>  ?NNN
** <li>  :VVV
** <li>  @VVV
** <li>  $VVV
** </ul>
**
** In the templates above, NNN represents an integer literal,
** and VVV represents an alphanumeric identifier.)^  ^The values of these
** parameters (also called "host parameter names" or "SQL parameters")
** can be set using the sqlite3_bind_*() routines defined here.
**
** ^The first argument to the sqlite3_bind_*() routines is always
** a pointer to the [sqlite3_stmt] object returned from
** [sqlite3_prepare_v2()] or its variants.
**
** ^The second argument is the index of the SQL parameter to be set.
** ^The leftmost SQL parameter has an index of 1.  ^When the same named
** SQL 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_index()] API if desired.  ^The index
** for "?NNN" parameters is the value of NNN.
** ^The NNN value must be between 1 and the [sqlite3_limit()]
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
**
** ^The third argument is the value to bind to the parameter.
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
** is ignored and the end result is the same as sqlite3_bind_null().
**
** ^(In those routines that have a fourth argument, its value is the
** number of bytes in the parameter.  To be clear: the value is the
** number of <u>bytes</u> in the value, not the number of characters.)^
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
** is negative, then the length of the string is
** the number of bytes up to the first zero terminator.
** If the fourth parameter to sqlite3_bind_blob() is negative, then
** the behavior is undefined.
** If a non-negative fourth parameter is provided to sqlite3_bind_text()
** or sqlite3_bind_text16() then that parameter must be the byte offset
** where the NUL terminator would occur assuming the string were NUL
** terminated.  If any NUL characters occur at byte offsets less than 
** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.
**
** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
** string after SQLite has finished with it.  ^The destructor is called
** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
** sqlite3_bind_text(), or sqlite3_bind_text16() fails.  
** ^If the fifth argument is
** the special value [SQLITE_STATIC], then SQLite assumes that the
** information is in static, unmanaged space and does not need to be freed.
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
** SQLite makes its own private copy of the data immediately, before
** the sqlite3_bind_*() routine returns.
**
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
** (just an integer to hold its size) while it is being processed.
** Zeroblobs are intended to serve as placeholders for BLOBs whose
** content is later written using
** [sqlite3_blob_open | incremental BLOB I/O] routines.
** ^A negative value for the zeroblob results in a zero-length BLOB.
**
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
** for the [prepared statement] or with a prepared statement for which
** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
** routine is passed a [prepared statement] that has been finalized, the
** result is undefined and probably harmful.
**
** ^Bindings are not cleared by the [sqlite3_reset()] routine.
** ^Unbound parameters are interpreted as NULL.
**
** ^The sqlite3_bind_* 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.
**
** See also: [sqlite3_bind_parameter_count()],
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
*/
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);

/*
** CAPI3REF: Number Of SQL Parameters
**
** ^This routine can be used to find the number of [SQL parameters]
** in a [prepared statement].  SQL parameters are tokens of the
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
** placeholders for values that are [sqlite3_bind_blob | bound]
** to the parameters at a later time.
**
** ^(This routine actually returns the index of the largest (rightmost)
** parameter. For all forms except ?NNN, this will correspond to the
** number of unique parameters.  If parameters of the ?NNN form are used,
** there may be gaps in the list.)^
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_name()], and
** [sqlite3_bind_parameter_index()].
*/
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);

/*
** CAPI3REF: Name Of A Host Parameter
**
** ^The sqlite3_bind_parameter_name(P,N) interface returns
** the name of the N-th [SQL parameter] in the [prepared statement] P.
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
** respectively.
** In other words, the initial ":" or "$" or "@" or "?"
** is included as part of the name.)^
** ^Parameters of the form "?" without a following integer have no name
** and are referred to as "nameless" or "anonymous parameters".
**
** ^The first host parameter has an index of 1, not 0.
**
** ^If the value N is out of range or if the N-th parameter is
** nameless, then NULL is returned.  ^The returned string is
** always in UTF-8 encoding even if the named parameter was
** originally specified as UTF-16 in [sqlite3_prepare16()] or
** [sqlite3_prepare16_v2()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
*/
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);

/*
** CAPI3REF: Index Of A Parameter With A Given Name
**
** ^Return the index of an SQL parameter given its name.  ^The
** index value returned is suitable for use as the second
** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
** is returned if no matching parameter is found.  ^The parameter
** name must be given in UTF-8 even if the original statement
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
**
** See also: [sqlite3_bind_blob|sqlite3_bind()],
** [sqlite3_bind_parameter_count()], and
** [sqlite3_bind_parameter_index()].
*/
SQLITE_API 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 [prepared statement].
** ^Use this routine to reset all host parameters to NULL.
*/
SQLITE_API 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
** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
** statement that does not return data (for example an [UPDATE]).
**
** See also: [sqlite3_data_count()]
*/
SQLITE_API 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 zero-terminated UTF-8 string
** and sqlite3_column_name16() returns a pointer to a zero-terminated
** UTF-16 string.  ^The first parameter is the [prepared statement]
** that implements the [SELECT] statement. ^The second parameter is the
** column number.  ^The leftmost column is number 0.
**
** ^The returned string pointer is valid until either the [prepared statement]
** is destroyed by [sqlite3_finalize()] or until the statement is automatically
** reprepared by the first call to [sqlite3_step()] for a particular run
** or until the next call to
** sqlite3_column_name() or sqlite3_column_name16() on the same column.
**
** ^If sqlite3_malloc() fails during the processing of either routine
** (for example during a conversion from UTF-8 to UTF-16) then a
** NULL pointer is returned.
**
** ^The name of a result column is the value of the "AS" clause for
** that column, if there is an AS clause.  If there is no AS clause
** then the name of the column is unspecified and may change from
** one release of SQLite to the next.
*/
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);

/*
** CAPI3REF: Source Of Data In A Query Result
**
** ^These routines provide a means to determine the database, table, and
** table column that is the origin of a particular result column in
** [SELECT] statement.
** ^The name of the database or table or column can be returned as
** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
** the database name, the _table_ routines return the table name, and
** the origin_ routines return the column name.
** ^The returned string is valid until the [prepared statement] is destroyed
** using [sqlite3_finalize()] or until the statement is automatically
** reprepared by the first call to [sqlite3_step()] for a particular run
** or until the same information is requested
** again in a different encoding.
**
** ^The names returned are the original un-aliased names of the
** database, table, and column.
**
** ^The first argument to these interfaces is a [prepared statement].
** ^These functions return information about the Nth result column returned by
** the statement, where N is the second function argument.
** ^The left-most column is column 0 for these routines.
**
** ^If the Nth column returned by the statement is an expression or
** subquery and is not a column value, then all of these functions return
** NULL.  ^These routine might also return NULL if a memory allocation error
** occurs.  ^Otherwise, they return the name of the attached database, table,
** or column that query result column was extracted from.
**
** ^As with all other SQLite APIs, those whose names end with "16" return
** UTF-16 encoded strings and the other functions return UTF-8.
**
** ^These APIs are only available if the library was compiled with the
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
**
** If two or more threads call one or more of these routines against the same
** prepared statement and column at the same time then the results are
** undefined.
**
** If two or more threads call one or more
** [sqlite3_column_database_name | column metadata interfaces]
** for the same [prepared statement] and result column
** at the same time then the results are undefined.
*/
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);

/*
** CAPI3REF: Declared Datatype Of A Query Result
**
** ^(The first parameter is a [prepared statement].
** If this statement is a [SELECT] statement and the Nth column of the
** returned result set of that [SELECT] is a table column (not an
** expression or subquery) then the declared type of the table
** column is returned.)^  ^If the Nth column of the result set is an
** expression or subquery, then a NULL pointer is returned.
** ^The returned string is always UTF-8 encoded.
**
** ^(For example, given the database schema:
**
** CREATE TABLE t1(c1 VARIANT);
**
** and the following statement to be compiled:
**
** SELECT c1 + 1, c1 FROM t1;
**
** 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.
*/
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);

/*
** CAPI3REF: Evaluate An SQL Statement
**
** After a [prepared statement] has been prepared using either
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
** must be called one or more times to evaluate the statement.
**
** The details of the behavior of the 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 legacy 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 [result codes] or
** [extended result codes] 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 an
** 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 [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 (for example,
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
** can be obtained by calling [sqlite3_reset()] on the
** [prepared statement].  ^In the "v2" interface,
** the more specific error code is returned directly by sqlite3_step().
**
** [SQLITE_MISUSE] means that the this routine was called inappropriately.
** Perhaps it was called on a [prepared statement] that has
** already been [sqlite3_finalize | finalized] or on one that had
** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
** be the case that the same database connection is being used by two or
** more threads at the same moment in time.
**
** For all versions of SQLite up to and including 3.6.23.1, a call to
** [sqlite3_reset()] was required after sqlite3_step() returned anything
** other than [SQLITE_ROW] before any subsequent invocation of
** sqlite3_step().  Failure to reset the prepared statement using 
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
** sqlite3_step().  But after version 3.6.23.1, sqlite3_step() began
** calling [sqlite3_reset()] automatically in this circumstance rather
** than returning [SQLITE_MISUSE].  This is not considered a compatibility
** break because any application that ever receives an SQLITE_MISUSE error
** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
** can be used to restore the legacy behavior.
**
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
** API always returns a generic error code, [SQLITE_ERROR], following any
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
** specific [error codes] that better describes the error.
** We admit that this is a goofy design.  The problem has been fixed
** with the "v2" interface.  If you prepare all of your SQL statements
** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
** then the more specific [error codes] are returned directly
** by sqlite3_step().  The use of the "v2" interface is recommended.
*/
SQLITE_API int sqlite3_step(sqlite3_stmt*);

/*
** CAPI3REF: Number of columns in a result set
**
** ^The sqlite3_data_count(P) interface returns the number of columns in the
** current row of the result set of [prepared statement] P.
** ^If prepared statement P does not have results ready to return
** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
** interfaces) then sqlite3_data_count(P) returns 0.
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
** will return non-zero if previous call to [sqlite3_step](P) returned
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
** where it always returns zero since each step of that multi-step
** pragma returns 0 columns of data.
**
** See also: [sqlite3_column_count()]
*/
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Fundamental Datatypes
** KEYWORDS: SQLITE_TEXT
**
** ^(Every value in SQLite has one of five fundamental datatypes:
**
** <ul>
** <li> 64-bit signed integer
** <li> 64-bit IEEE floating point number
** <li> string
** <li> BLOB
** <li> NULL
** </ul>)^
**
** 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: Result Values From A Query
** KEYWORDS: {column access functions}
**
** These routines form the "result set" interface.
**
** ^These routines return information about a single column of the current
** result row of a query.  ^In every case the first argument is a pointer
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
** that was returned from [sqlite3_prepare_v2()] or one of its variants)
** and the second argument is the index of the column for which information
** should be returned. ^The leftmost column of the result set has the index 0.
** ^The number of columns in the result can be determined using
** [sqlite3_column_count()].
**
** If the SQL statement does not currently point to a valid row, or if the
** column index is out of range, the result is undefined.
** These routines may only be called when the most recent call to
** [sqlite3_step()] has returned [SQLITE_ROW] and neither
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
** If any of these routines are called after [sqlite3_reset()] or
** [sqlite3_finalize()] or after [sqlite3_step()] has returned
** something other than [SQLITE_ROW], the results are undefined.
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
** are called from a different thread while any of these routines
** are pending, then the results are undefined.
**
** ^The sqlite3_column_type() routine returns the
** [SQLITE_INTEGER | datatype code] for the initial data type
** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].  The value
** returned by sqlite3_column_type() is only meaningful if no type
** conversions have occurred as described below.  After a type conversion,
** the value returned by sqlite3_column_type() is undefined.  Future
** versions of SQLite may change the behavior of sqlite3_column_type()
** following a type conversion.
**
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
** routine returns the number of bytes in that BLOB or string.
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
** the string to UTF-8 and then returns the number of bytes.
** ^If the result is a numeric value then sqlite3_column_bytes() uses
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
** the number of bytes in that string.
** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
**
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
** routine returns the number of bytes in that BLOB or string.
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
** the string to UTF-16 and then returns the number of bytes.
** ^If the result is a numeric value then sqlite3_column_bytes16() uses
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
** the number of bytes in that string.
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
**
** ^The values returned by [sqlite3_column_bytes()] and 
** [sqlite3_column_bytes16()] do not include the zero terminators at the end
** of the string.  ^For clarity: the values returned by
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
** bytes in the string, not the number of characters.
**
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
** even empty strings, are always zero-terminated.  ^The return
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
**
** ^The object returned by [sqlite3_column_value()] is an
** [unprotected sqlite3_value] object.  An unprotected sqlite3_value object
** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
** If the [unprotected sqlite3_value] object returned by
** [sqlite3_column_value()] is used in any other way, including calls
** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
** or [sqlite3_value_bytes()], then the behavior is undefined.
**
** These routines attempt to convert the value where appropriate.  ^For
** example, if the internal representation is FLOAT and a text result
** is requested, [sqlite3_snprintf()] is used internally to perform the
** conversion automatically.  ^(The following table details the conversions
** that are applied:
**
** <blockquote>
** <table border="1">
** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
**
** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
** <tr><td>  NULL    <td>   TEXT    <td> Result is NULL pointer
** <tr><td>  NULL    <td>   BLOB    <td> Result is NULL pointer
** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
** <tr><td>  FLOAT   <td> INTEGER   <td> Convert from float to integer
** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
** <tr><td>  FLOAT   <td>   BLOB    <td> Same as FLOAT->TEXT
** <tr><td>  TEXT    <td> INTEGER   <td> Use atoi()
** <tr><td>  TEXT    <td>  FLOAT    <td> Use atof()
** <tr><td>  TEXT    <td>   BLOB    <td> No change
** <tr><td>  BLOB    <td> INTEGER   <td> Convert to TEXT then use atoi()
** <tr><td>  BLOB    <td>  FLOAT    <td> Convert to TEXT then use atof()
** <tr><td>  BLOB    <td>   TEXT    <td> Add a zero terminator if needed
** </table>
** </blockquote>)^
**
** The table above makes reference to standard C library functions atoi()
** and atof().  SQLite does not really use these functions.  It has its
** own equivalent internal routines.  The atoi() and atof() names are
** used in the table for brevity and because they are familiar to most
** C programmers.
**
** Note that when type conversions occur, pointers returned by prior
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
** sqlite3_column_text16() may be invalidated.
** Type conversions and pointer invalidations might occur
** in the following cases:
**
** <ul>
** <li> The initial content is a BLOB and sqlite3_column_text() or
**      sqlite3_column_text16() is called.  A zero-terminator might
**      need to be added to the string.</li>
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
**      sqlite3_column_text16() is called.  The content must be converted
**      to UTF-16.</li>
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
**      sqlite3_column_text() is called.  The content must be converted
**      to UTF-8.</li>
** </ul>
**
** ^Conversions between UTF-16be and UTF-16le are always done in place and do
** not invalidate a prior pointer, though of course the content of the buffer
** that the prior pointer references will have been modified.  Other kinds
** of conversion are done in place when it is possible, but sometimes they
** are not possible and in those cases prior pointers are invalidated.
**
** The safest and easiest to remember policy is to invoke these routines
** in one of the following ways:
**
** <ul>
**  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
**  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
**  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
** </ul>
**
** In other words, you should call sqlite3_column_text(),
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
** into the desired format, then invoke sqlite3_column_bytes() or
** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
** to sqlite3_column_text() or sqlite3_column_blob() with calls to
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
** with calls to sqlite3_column_bytes().
**
** ^The pointers returned are valid until a type conversion occurs as
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
** and BLOBs is freed automatically.  Do <b>not</b> pass the pointers returned
** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
** [sqlite3_free()].
**
** ^(If a memory allocation error occurs during the evaluation of any
** of these routines, a default value is returned.  The default value
** is either the integer 0, the floating point number 0.0, or a NULL
** pointer.  Subsequent calls to [sqlite3_errcode()] will return
** [SQLITE_NOMEM].)^
*/
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);

/*
** CAPI3REF: Destroy A Prepared Statement Object
**
** ^The sqlite3_finalize() function is called to delete a [prepared statement].
** ^If the most recent evaluation of the statement encountered no errors
** or if the statement is never been evaluated, then sqlite3_finalize() returns
** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
** sqlite3_finalize(S) returns the appropriate [error code] or
** [extended error code].
**
** ^The sqlite3_finalize(S) routine can be called at any point during
** the life cycle of [prepared statement] S:
** before statement S is ever evaluated, after
** one or more calls to [sqlite3_reset()], or after any call
** to [sqlite3_step()] regardless of whether or not the statement has
** completed execution.
**
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
**
** The application must finalize every [prepared statement] in order to avoid
** resource leaks.  It is a grievous error for the application to try to use
** a prepared statement after it has been finalized.  Any use of a prepared
** statement after it has been finalized can result in undefined and
** undesirable behavior such as segfaults and heap corruption.
*/
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Reset A Prepared Statement Object
**
** The sqlite3_reset() function is called to reset a [prepared statement]
** object back to its initial state, ready to be re-executed.
** ^Any SQL statement variables that had values bound to them using
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
** Use [sqlite3_clear_bindings()] to reset the bindings.
**
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
** back to the beginning of its program.
**
** ^If the most recent call to [sqlite3_step(S)] for the
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
** or if [sqlite3_step(S)] has never before been called on S,
** then [sqlite3_reset(S)] returns [SQLITE_OK].
**
** ^If the most recent call to [sqlite3_step(S)] for the
** [prepared statement] S indicated an error, then
** [sqlite3_reset(S)] returns an appropriate [error code].
**
** ^The [sqlite3_reset(S)] interface does not change the values
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
*/
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);

/*
** CAPI3REF: Create Or Redefine SQL Functions
** KEYWORDS: {function creation routines}
** KEYWORDS: {application-defined SQL function}
** KEYWORDS: {application-defined SQL functions}
**
** ^These functions (collectively known as "function creation routines")
** are used to add SQL functions or aggregates or to redefine the behavior
** of existing SQL functions or aggregates.  The only differences between
** these routines are the text encoding expected for
** the second parameter (the name of the function being created)
** and the presence or absence of a destructor callback for
** the application data pointer.
**
** ^The first parameter is the [database connection] to which the SQL
** function is to be added.  ^If an application uses more than one database
** connection then application-defined SQL functions must be added
** to each database connection separately.
**
** ^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 in a UTF-8
** representation, exclusive of the zero-terminator.  ^Note that the name
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.  
** ^Any attempt to create a function with a longer name
** will result in [SQLITE_MISUSE] being returned.
**
** ^The third parameter (nArg)
** is the number of arguments that the SQL function or
** aggregate takes. ^If this parameter is -1, then the SQL function or
** aggregate may take any number of arguments between 0 and the limit
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
** parameter is less than -1 or greater than 127 then the behavior is
** undefined.
**
** ^The fourth parameter, eTextRep, specifies what
** [SQLITE_UTF8 | text encoding] this SQL function prefers for
** its parameters.  Every SQL function implementation must be able to work
** with UTF-8, UTF-16le, or UTF-16be.  But some implementations may be
** more efficient with one encoding than another.  ^An application may
** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
** times with the same function but with different values of eTextRep.
** ^When multiple implementations of the same function are available, SQLite
** will pick the one that involves the least amount of data conversion.
** If there is only a single implementation which does not care what text
** encoding is used, then the fourth argument should be [SQLITE_ANY].
**
** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
** function can gain access to this pointer using [sqlite3_user_data()].)^
**
** ^The sixth, seventh and eighth 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 must be passed as the xStep and xFinal
** parameters. ^An aggregate SQL function requires an implementation of xStep
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
** SQL function or aggregate, pass NULL pointers for all three function
** callbacks.
**
** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
** then it is destructor for the application data pointer. 
** The destructor is invoked when the function is deleted, either by being
** overloaded or when the database connection closes.)^
** ^The destructor is also invoked if the call to
** sqlite3_create_function_v2() fails.
** ^When the destructor callback of the tenth parameter is invoked, it
** is passed a single argument which is a copy of the application data 
** pointer which was the fifth parameter to sqlite3_create_function_v2().
**
** ^It is permitted to register multiple implementations of the same
** functions with the same name but with either differing numbers of
** arguments or differing preferred text encodings.  ^SQLite will use
** the implementation that most closely matches the way in which the
** SQL function is used.  ^A function implementation with a non-negative
** nArg parameter is a better match than a function implementation with
** a negative nArg.  ^A function where the preferred text encoding
** matches the database encoding is a better
** match than a function where the encoding is different.  
** ^A function where the encoding difference is between UTF16le and UTF16be
** is a closer match than a function where the encoding difference is
** between UTF8 and UTF16.
**
** ^Built-in functions may be overloaded by new application-defined functions.
**
** ^An application-defined function is permitted to call other
** SQLite interfaces.  However, such calls must not
** close the database connection nor finalize or reset the prepared
** statement in which the function is running.
*/
SQLITE_API int sqlite3_create_function(
  sqlite3 *db,
  const char *zFunctionName,
  int nArg,
  int eTextRep,
  void *pApp,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
  void (*xFinal)(sqlite3_context*)
);
SQLITE_API int sqlite3_create_function16(
  sqlite3 *db,
  const void *zFunctionName,
  int nArg,