Number of SQL statement executions

When the SQL statement cache is enabled, the database server inserts a qualified SQL statement and its memory structures immediately in the SQL statement cache by default.

If your workload has a disproportionate number of ad hoc queries, use the STMT_CACHE_HITS configuration parameter to specify the number of times an SQL statement is executed before the database server places a fully cached entry in the statement cache.

When the STMT_CACHE_HITS configuration parameter is greater than 0 and the number of times the SQL statement has been executed is less than STMT_CACHE_HITS, the database server inserts key-only entries in the cache. This specification minimizes unshared memory structures from occupying the statement cache, which leaves more memory for SQL statements that applications use often.

Monitor the number of hits on the SQL statement cache to determine if your workload is using this cache effectively. The following sections describe ways to monitor the SQL statement cache hits.


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