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  • mysqlnd_qc_set_cache_condition

    Set conditions for automatic caching


bool mysqlnd_qc_set_cache_condition(int condition_type,
                                    mixed condition,
                                    mixed condition_option);

Sets a condition for automatic caching of statements which do not contain the necessary SQL hints to enable caching of them.



Type of the condition. The only allowed value is MYSQLND_QC_CONDITION_META_SCHEMA_PATTERN.


Parameter for the condition set with condition_type. Parameter type and structure depend on condition_type

If condition_type equals MYSQLND_QC_CONDITION_META_SCHEMA_PATTERN condition must be a string. The string sets a pattern. Statements are cached if table and database meta data entry of their result sets match the pattern. The pattern is checked for a match with the db and org_table meta data entries provided by the underlying MySQL client server library. Please, check the MySQL Reference manual for details about the two entries. The db and org_table values are concatenated with a dot (.) before matched against condition. Pattern matching supports the wildcards % and _. The wildcard % will match one or many arbitrary characters. _ will match one arbitrary character. The escape symbol is backslash.


Option for condition. Type and structure depend on condition_type.

If condition_type equals MYSQLND_QC_CONDITION_META_SCHEMA_PATTERN condition_options is the TTL to be used.


Example 7.328 mysqlnd_qc_set_cache_condition example

/* Cache all accesses to tables with the name "new%" in schema/database "db_example" for 1 second */
if (!mysqlnd_qc_set_cache_condition(MYSQLND_QC_CONDITION_META_SCHEMA_PATTERN, "", 1)) {
  die("Failed to set cache condition!");
$mysqli = new mysqli("host", "user", "password", "db_example", "port");
/* cached although no SQL hint given  */
$mysqli->query("SELECT id, title FROM news");
$pdo_mysql = new PDO("mysql:host=host;dbname=db_example;port=port", "user", "password");
/* not cached: no SQL hint, no pattern match */
$pdo_mysql->query("SELECT id, title FROM latest_news");
/* cached: TTL 1 second, pattern match */
$pdo_mysql->query("SELECT id, title FROM news");

Return Values

Returns TRUE on success or FALSE on FAILURE.

See Also

Quickstart: pattern based caching