206 lines
6.1 KiB
C
206 lines
6.1 KiB
C
/*
|
|
** 2007 May 7
|
|
**
|
|
** 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 file defines various limits of what SQLite can process.
|
|
*/
|
|
|
|
/*
|
|
** The maximum length of a TEXT or BLOB in bytes. This also
|
|
** limits the size of a row in a table or index.
|
|
**
|
|
** The hard limit is the ability of a 32-bit signed integer
|
|
** to count the size: 2^31-1 or 2147483647.
|
|
*/
|
|
#ifndef SQLITE_MAX_LENGTH
|
|
#define SQLITE_MAX_LENGTH 1000000000
|
|
#endif
|
|
|
|
/*
|
|
** This is the maximum number of
|
|
**
|
|
** * Columns in a table
|
|
** * Columns in an index
|
|
** * Columns in a view
|
|
** * Terms in the SET clause of an UPDATE statement
|
|
** * Terms in the result set of a SELECT statement
|
|
** * Terms in the GROUP BY or ORDER BY clauses of a SELECT statement.
|
|
** * Terms in the VALUES clause of an INSERT statement
|
|
**
|
|
** The hard upper limit here is 32676. Most database people will
|
|
** tell you that in a well-normalized database, you usually should
|
|
** not have more than a dozen or so columns in any table. And if
|
|
** that is the case, there is no point in having more than a few
|
|
** dozen values in any of the other situations described above.
|
|
*/
|
|
#ifndef SQLITE_MAX_COLUMN
|
|
#define SQLITE_MAX_COLUMN 2000
|
|
#endif
|
|
|
|
/*
|
|
** The maximum length of a single SQL statement in bytes.
|
|
**
|
|
** It used to be the case that setting this value to zero would
|
|
** turn the limit off. That is no longer true. It is not possible
|
|
** to turn this limit off.
|
|
*/
|
|
#ifndef SQLITE_MAX_SQL_LENGTH
|
|
#define SQLITE_MAX_SQL_LENGTH 1000000000
|
|
#endif
|
|
|
|
/*
|
|
** The maximum depth of an expression tree. This is limited to
|
|
** some extent by SQLITE_MAX_SQL_LENGTH. But sometime you might
|
|
** want to place more severe limits on the complexity of an
|
|
** expression.
|
|
**
|
|
** A value of 0 used to mean that the limit was not enforced.
|
|
** But that is no longer true. The limit is now strictly enforced
|
|
** at all times.
|
|
*/
|
|
#ifndef SQLITE_MAX_EXPR_DEPTH
|
|
#define SQLITE_MAX_EXPR_DEPTH 1000
|
|
#endif
|
|
|
|
/*
|
|
** The maximum number of terms in a compound SELECT statement.
|
|
** The code generator for compound SELECT statements does one
|
|
** level of recursion for each term. A stack overflow can result
|
|
** if the number of terms is too large. In practice, most SQL
|
|
** never has more than 3 or 4 terms. Use a value of 0 to disable
|
|
** any limit on the number of terms in a compount SELECT.
|
|
*/
|
|
#ifndef SQLITE_MAX_COMPOUND_SELECT
|
|
#define SQLITE_MAX_COMPOUND_SELECT 500
|
|
#endif
|
|
|
|
/*
|
|
** The maximum number of opcodes in a VDBE program.
|
|
** Not currently enforced.
|
|
*/
|
|
#ifndef SQLITE_MAX_VDBE_OP
|
|
#define SQLITE_MAX_VDBE_OP 25000
|
|
#endif
|
|
|
|
/*
|
|
** The maximum number of arguments to an SQL function.
|
|
*/
|
|
#ifndef SQLITE_MAX_FUNCTION_ARG
|
|
#define SQLITE_MAX_FUNCTION_ARG 127
|
|
#endif
|
|
|
|
/*
|
|
** The maximum number of in-memory pages to use for the main database
|
|
** table and for temporary tables. The SQLITE_DEFAULT_CACHE_SIZE
|
|
*/
|
|
#ifndef SQLITE_DEFAULT_CACHE_SIZE
|
|
#define SQLITE_DEFAULT_CACHE_SIZE 2000
|
|
#endif
|
|
#ifndef SQLITE_DEFAULT_TEMP_CACHE_SIZE
|
|
#define SQLITE_DEFAULT_TEMP_CACHE_SIZE 500
|
|
#endif
|
|
|
|
/*
|
|
** The default number of frames to accumulate in the log file before
|
|
** checkpointing the database in WAL mode.
|
|
*/
|
|
#ifndef SQLITE_DEFAULT_WAL_AUTOCHECKPOINT
|
|
#define SQLITE_DEFAULT_WAL_AUTOCHECKPOINT 1000
|
|
#endif
|
|
|
|
/*
|
|
** The maximum number of attached databases. This must be between 0
|
|
** and 62. The upper bound on 62 is because a 64-bit integer bitmap
|
|
** is used internally to track attached databases.
|
|
*/
|
|
#ifndef SQLITE_MAX_ATTACHED
|
|
#define SQLITE_MAX_ATTACHED 10
|
|
#endif
|
|
|
|
/*
|
|
** The maximum value of a ?nnn wildcard that the parser will accept.
|
|
*/
|
|
#ifndef SQLITE_MAX_VARIABLE_NUMBER
|
|
#define SQLITE_MAX_VARIABLE_NUMBER 999
|
|
#endif
|
|
|
|
/* Maximum page size. The upper bound on this value is 65536. This a limit
|
|
** imposed by the use of 16-bit offsets within each page.
|
|
**
|
|
** Earlier versions of SQLite allowed the user to change this value at
|
|
** compile time. This is no longer permitted, on the grounds that it creates
|
|
** a library that is technically incompatible with an SQLite library
|
|
** compiled with a different limit. If a process operating on a database
|
|
** with a page-size of 65536 bytes crashes, then an instance of SQLite
|
|
** compiled with the default page-size limit will not be able to rollback
|
|
** the aborted transaction. This could lead to database corruption.
|
|
*/
|
|
#ifdef SQLITE_MAX_PAGE_SIZE
|
|
#undef SQLITE_MAX_PAGE_SIZE
|
|
#endif
|
|
#define SQLITE_MAX_PAGE_SIZE 65536
|
|
|
|
/*
|
|
** The default size of a database page.
|
|
*/
|
|
#ifndef SQLITE_DEFAULT_PAGE_SIZE
|
|
#define SQLITE_DEFAULT_PAGE_SIZE 1024
|
|
#endif
|
|
#if SQLITE_DEFAULT_PAGE_SIZE > SQLITE_MAX_PAGE_SIZE
|
|
#undef SQLITE_DEFAULT_PAGE_SIZE
|
|
#define SQLITE_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
|
|
#endif
|
|
|
|
/*
|
|
** Ordinarily, if no value is explicitly provided, SQLite creates databases
|
|
** with page size SQLITE_DEFAULT_PAGE_SIZE. However, based on certain
|
|
** device characteristics (sector-size and atomic write() support),
|
|
** SQLite may choose a larger value. This constant is the maximum value
|
|
** SQLite will choose on its own.
|
|
*/
|
|
#ifndef SQLITE_MAX_DEFAULT_PAGE_SIZE
|
|
#define SQLITE_MAX_DEFAULT_PAGE_SIZE 8192
|
|
#endif
|
|
#if SQLITE_MAX_DEFAULT_PAGE_SIZE > SQLITE_MAX_PAGE_SIZE
|
|
#undef SQLITE_MAX_DEFAULT_PAGE_SIZE
|
|
#define SQLITE_MAX_DEFAULT_PAGE_SIZE SQLITE_MAX_PAGE_SIZE
|
|
#endif
|
|
|
|
/*
|
|
** Maximum number of pages in one database file.
|
|
**
|
|
** This is really just the default value for the max_page_count pragma.
|
|
** This value can be lowered (or raised) at run-time using that the
|
|
** max_page_count macro.
|
|
*/
|
|
#ifndef SQLITE_MAX_PAGE_COUNT
|
|
#define SQLITE_MAX_PAGE_COUNT 1073741823
|
|
#endif
|
|
|
|
/*
|
|
** Maximum length (in bytes) of the pattern in a LIKE or GLOB
|
|
** operator.
|
|
*/
|
|
#ifndef SQLITE_MAX_LIKE_PATTERN_LENGTH
|
|
#define SQLITE_MAX_LIKE_PATTERN_LENGTH 50000
|
|
#endif
|
|
|
|
/*
|
|
** Maximum depth of recursion for triggers.
|
|
**
|
|
** A value of 1 means that a trigger program will not be able to itself
|
|
** fire any triggers. A value of 0 means that no trigger programs at all
|
|
** may be executed.
|
|
*/
|
|
#ifndef SQLITE_MAX_TRIGGER_DEPTH
|
|
#define SQLITE_MAX_TRIGGER_DEPTH 1000
|
|
#endif
|