1. Performance Tuning Guide
  2. Ongoing Tuning of Siebel SQL Statements

Ongoing Tuning of Siebel SQL Statements

Over time, new plans are evaluated and preserved when their performance improvements are significant. Subsequently, these plans can be evolved to “accepted” if their performance is superior (1.5 times better performance is default and can be increased to provide more guarantee) to the baseline’s SQL plan. To have full control of “SPM Evolve Advisor Task”, it is recommended to set the SET_EVOLVE_TASK_PARAMETER to MANUAL and set the accept_plans to FALSE. These settings allow the reports to be reviewed and the plans can be evolved manually.

Also, after any new Siebel, your releases or Oracle database major upgrades, it is highly recommended to thoroughly test in the performance testing environment making sure that all new SQL statements or modified ones are meeting the performance requirements.

There are number of ways to verify and address SQL performance issues that Oracle recommends:

  1. SQL Profile using SQL Tuning Adviser
  2. SQL Plan Management
  3. Real Application Testing (not currently supported on ADB)
    1. Database Replay: Record a workload and replay it
    2. SQL Performance Analyzer: Find plan regressions prior to a change

For more information about SQL Tuning Adviser and SQL Plan Management refer to Oracle 19c SQL Tuning Guide, Chapters 26 & 28, respectively, or Database Performance Tuning Guide in Oracle Database reference documentation. For Real Application Testing, refer to Oracle Testing Guide.