Reviewing the SQL Performance Analyzer Report: Global Statistics Details

You can use the SQL Performance Analyzer Report to obtain detailed statistics for the SQL workload comparison. The details chart enables you to drill down into the performance of SQL statements that appears in the report. Use the information in this section to investigate why the performance of a particular SQL statement regressed.

To review global statistics details:

1. In the Projected Workload Elapsed Time subsection, click the impact percentage of the SQL statements for which you want to view details. To view SQL statements whose performance:

   • Improved, click the percentage for Improvement Impact

   • Regressed, click the percentage for Regression Impact

   • Improved or regressed, click the percentage for Overall Impact

   A table including the detailed statistics appears. Depending on the type of SQL statements chosen, the following columns are included:

   • SQL ID

     This column indicates the ID of the SQL statement.

   • Net Impact on Workload (%)

     This column indicates the impact of the system change relative to the performance of the SQL workload.

   • Elapsed Time

     This column indicates the total time (in seconds) of the SQL statement execution.

   • Net Impact on SQL (%)

     This column indicates the local impact of the change on the performance of a particular SQL statement.

   • New Plan

     This column indicates whether the SQL execution plan changed.

2. To view details about a particular SQL statement, click the SQL ID link for the SQL statement that you are interested in.

   The SQL Details page appears.

   You can use this page to access the SQL text and obtain low-level details about the SQL statement, such as CPU time, buffer gets, and optimizer cost.