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