/*

** 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.

**

** @(#) $Id: sqliteLimit.h,v 1.8 2008/03/26 15:56:22 drh Exp $

*/

/*

** 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 100

#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 maximum number of attached databases.  This must be between 0

** and 30.  The upper bound on 30 is because a 32-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 32768.  This a limit

** imposed by the necessity of storing the value in a 2-byte unsigned integer

** and the fact that the page size must be a power of 2.

*/

#ifndef SQLITE_MAX_PAGE_SIZE

# define SQLITE_MAX_PAGE_SIZE 32768

#endif

/*

** 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