DB2 graphic  QMF Version 8

Maintaining the control tables

Most control-table maintenance cannot be done under QMF, because QMF relies on these tables for its operations. You can issue your maintenance queries in batch-mode TSO through the DSN processor, or interactively through the SPUFI facility of DB2I.

Workstation database server users: Additionally, you can use the DB2 Command Line Processor from the local operating system environment of the database.

You can find information on these subjects in the DB2 UDB for z/OS Administration Guide.

No one should be using QMF during maintenance work. To ensure this, apply the DB2-STOP DATABASE command to one of the table spaces containing a control table. You can then do maintenance operations on the other control tables and indexes. You can do either of the following:

For a description of the DB2-STOP DATABASE command, see DB2 UDB for z/OS Utility Guide and Reference.

Monitoring and reorganizing the control tables

You should forestall maintenance problems by monitoring the condition of the control tables through the DB2 system catalog. For more information, see the DB2 UDB for z/OS Administration Guide.

Running the RUNSTATS utility

You periodically run the RUNSTATS utility on the control tables and indexes to add current statistics to certain DB2 system tables. You then query these tables and examine these statistics to decide whether reorganization is required.

If reorganization is required, do the following:

  1. Run the REORG utility.
  2. Rerun the RUNSTATS utility.
  3. Query the updated system tables again to see if the reorganization improved the statistics.

At its most effective, reorganization can minimize the space requirements for the control tables and indexes and increase the efficiency of QMF operations.

The DB2 UDB for z/OS Administration Guide suggests that you rebind your most critical applications after reorganization so that the most efficient search paths can be selected. This suggests that the QMF application plan be rebound after each such reorganization.


Go to the previous page Go to the next page

Downloads | Library | Support | Support Policy | Terms of use | Feedback
Copyright IBM Corporation 1982,2004 Copyright IBM Corporation 1982, 2004
timestamp Last updated: March, 2004