If the access plan has regressed and you are using DB2 for z/OS Version
9 or higher, you can revert to a previously stored access plan.
Before you begin
- Compare access plans for SQL statements from packages.
- You must have the authorization and privilege to execute the REBIND
PACKAGE command and execute privilege on the stored procedure ADMIN_COMMAND_DSN.
- If you are using DB2® Version
9 for z/OS®,
the patch for APAR PK52522 must be installed.
- The original access plan has been captured in the access plan
repository in the DB2 for z/OS subsystem
catalog, specifically in the SYSIBM.SYSQUERY, SYSIBM.SYSQUERYPLAN,
and SYSIBM.SYSQUERYOPTS tables.
- When preserving the original access plan, the PLANMGMT option
must be set to BASIC or EXTENDED.
If you are using DB2 Version
10 for z/OS,
the PLANMGMTSCOPE option must be set to ALL or STATIC.
Procedure
- In the Manage and Tune page of the workflow assistant,
select a workload that contains the access plan comparison results.
- Click the View Comparison Result icon
and drill down to review the Packages section.
- Select the source or target package with the access plan
that regressed and click the Plan Management icon.