| /* |
| ** 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 |