QMF for TSO/CICS introduces improved usage of the Db2 Dynamic Statement Cache with support for statement concentration with literals.
When Db2 dynamic statement caching is active, you can specify that Db2 exclude literal constants that are in dynamic SQL statements when searching for a statement text match in the dynamic statement cache. This can result in more sharing and reuse of cached statements.
This can improve performance of dynamic query processing.
This Db2 performance feature can be achieved through QMF/TSO with the activation of the QMF global variable DSQEC_CON_CSWL. When DSQEC_CON_CSWL set to a value of '1', QMF will append the Db2 prepare attribute CONCENTRATE STATEMENTS WITH LITERALS to all user driven SQL SELECT statements. If activated, QMF commands such as RUN QUERY, DISPLAY TABLE, EXPORT TABLE and PRINT TABLE would be eligible for this Db2 performance improvement. Set the QMF global variable from a QMF procedure, Q.GLOBAL_VARS table or from the QMF command line like this:
QMF for TSO/CICS APAR PH05288 (PTF UI60108) must be applied to implement this enhancement.
Note that there is no rebinding of QMF for TSO/CICS packages to achieve this support!
See the Db2 for z/OS publications for more information on the
Db2 dynamic statement cache and
concentrate statements with literals prepare attribute.