NoCOUG Journal – SQL Plan Management for Performance Testing
NoCOUG Journal, August 2012 – Maris Elsins
This article is the third in a series by Pythian experts that is being published as the “Performance Corner” column in the NoCOUG Journal. SQL Plan Management (SPM) is a feature introduced with Oracle Database 11gR1 that effectively addresses the long-standing problem of unpredictable effects caused on the performance of SQL statements by the changes of optimizer statistics, system configuration, and schema objects, or the patching and upgrading of the database software. In many cases the cause of the degraded performance is the different execution plan produced by the optimizer for the same statement, compared to the one used before.