The sa_diagnostic_cachecontents table is owned by the dbo user. When diagnostic tracing is enabled, periodic snapshots of the cache contents are taken. The sa_diagnostic_cachecontents table records the number of table pages for each table in the cache at the time the snapshot was taken, and the number of rows in each table. The optimizer can use this information to recreate the conditions under which a query was originally optimized, and then make optimization decisions.
Data in the sa_diagnostic_cachecontents table is updated every 20 seconds, as long as there is query activity.
There are two versions of this table: sa_diagnostic_cachecontents, and sa_tmp_diagnostic_cachecontents.
Discuter à propos de cette page dans DocCommentXchange.
|Copyright © 2012, iAnywhere Solutions, Inc. - SQL Anywhere 12.0.1|