5 Creating a Post-Change SQL Trial

After computing the pre-change SQL performance data, you can perform the system change on the test system. Before making the system change, ensure that you have executed the SQL workload in the initial environment to generate the pre-change performance data. For example, if you are testing how changing a database initialization parameter will affect SQL performance, execute the SQL workload once before changing the database initialization parameter to a new value. Depending on the type of change you are making, it may be necessary to reconfigure the environment on the test system to match the new environment for which you want to perform SQL performance analysis. For more information, see "Making a System Change".


You can optionally run SQL trials on a remote system by providing access to a public database link. When conducting remote SQL trials, the database version of the remote database where the SQL statements are executed must be less than or equal to the database version of the database to which it connects. Starting with Oracle Database release, the remote database can be a read-only database, such as an Oracle Active Data Guard instance.

"SQL Performance Analyzer" lists examples of possible system changes that can be analyzed using SQL Performance Analyzer. For example, you may want to determine how a database initialization parameter change or database upgrade will affect SQL performance. You may also decide to change the system based on recommendations from an advisor such as Automatic Database Diagnostic Monitor (ADDM), SQL Tuning Advisor, or SQL Access Advisor.

After you have made the system change, you can build the post-change version of performance data by executing the SQL workload again. SQL Performance Analyzer will store the results from executing the SQL statements in a post-change SQL trial. For more information, see "Measuring the Post-Change SQL Performance".

This section described how to create the post-change SQL trial and contains the following topics:


The primary interface for creating a post-change SQL trial is Oracle Enterprise Manager. If for some reason Oracle Enterprise Manager is unavailable, you can create a post-change SQL trial using the DBMS_SQLPA PL/SQL package.


Before making the system change creating a post-change SQL trial, you need to create a pre-change SQL trial, as described in Creating a Pre-Change SQL Trial .