Version 12.1 changes

These are enhancements to QMF Version 12 Release 1.

Above the bar storage requirement changes

Above the bar storage is required for LOB and XML data type retrieval. For the LOB and XML data type and the 64 bit spill support, you can increase the amount of above the bar storage (MEMLIMIT).

QMF utilizes above the bar storage (storage above the 2-gigabyte bar). To control the amount of real and auxiliary storage that an address space can use for memory objects at one time, your site may have established an installation default MEMLIMIT that sets the total number of usable virtual pages above the bar for a single address space. If the default is not sufficient, QMF cannot be started.

The current default for MEMLIMIT for z/OS® V1R10.0 and later is 2G. The default for z/OS versions prior to that is 0, meaning that no address space can use virtual storage above the bar. You should verify that the MEMLIMIT setting for your site is at least 2G for QMF. This amount is recommended for scalability of a wide range of objects. QMF only uses as much storage above the bar as it needs, and only as long as it is needed; the storage is released immediately after a job or process is complete.

To set the MEMLIMIT parameter, use one of the following methods:

  • Set an installation default on the MEMLIMIT parameter in the SMFPRMxx PARMLIB member.
  • Issue the SET SMF or SETSMF command.
  • Add either the MEMLIMIT parameter or REGION=0 to the logon procedure TSO JCL or the job JCL.
  • Specify MEMLIMIT in a IEFUSI exit routine; if you do so, this MEMLIMIT setting overrides all other MEMLIMIT settings.

The following example shows the MEMLIMIT parameter added to a TSO logon procedure:


See the IBM® z/OS documentation for your version of z/OS for additional information about MEMLIMIT.

Note: As a result of these requirement changes, existing QMF TSO address space allocations might need to be changed.

QMF Classic Edition, QMF for Z/OS, and QMF Enterprise Edition changes

QMF Classic Edition now consists of QMF for TSO and CICS®, QMF HPO and QMF Applications (QMF Enhanced Editor and QMF Analytics for TSO). QMF HPO and QMF Applications are new components to QMF Classic Edition. Also, QMF for z/OS and QMF Enterprise Edition now include the QMF Data Service component in the existing suite of QMF for Workstation/WebSphere, QMF for TSO and CICS, QMF HPO and QMF Applications.

Access to non Db2 data sources (VSAM, IMS, etc.)

Using the QMF Data Service feature, QMF for z/OS, and QMF Enterprise Edition, you can access non-Db2 data sources. These data sources include but are not limited to: VSAM, IMS, SMF data, and many more. Data is retrieved through QMF queries and can be formatted and manipulated in traditional QMF forms. For the complete list of data source access available, reference the QMF publications.

Report preview options

After proper setting of the DSQDC_DISPLAY_RPT global variable, you can enter a report mini-session, where queries can be run to view potential output without actually committing the results. The report mini-session can be useful for running and testing SELECT with change type queries. Upon exiting the report mini-session, you will be prompted to COMMIT or ROLLBACK the query.

Performance and storage improvements

This release of Db2® QMF includes the following performance and storage improvements:

Additional database thread capabilities

Using the new QMF program parameter option DSQSMTHD, you can use a second database thread. The second thread can be used for RUN QUERY and DISPLAY TABLE command processing. Usage of a second data base thread can assist with performance issues on SAVE operations with an incomplete report outstanding. Additionally, usage of the second thread can reduce storage requirements for SAVE DATA commands on large report objects because rows do not need to reside in storage but can be retrieved from the database and inserted into the new table as needed.

Increased fetch buffer size

Using the DSQEC_BUFFER_SIZE global variable, the QMF internal storage area used to fetch data base row data can be increased. By changing the default from 4 kilobytes to a value up to 256 kilobytes, QMF can increase the amount of data fetched in a single call to the database. Less calls to the database reduces the amount of time it takes to complete the report, which can result in significant performance improvements.

Query By Example (QBE) and Prompted Query (PQ) enhancements

The QBE and PQ interface has been updated to support the TABLE keyword when specified on the RUN QUERY command.

Binary data formatting improvements

The QMF FORM now allows the 'C' edit code for binary column data. This allows you to store known character data in binary columns to properly format report content.

QMF serviceability

This release of Db2 QMF includes the following serviceability enhancement:

The global variable DSQEC_TRACE_MODULE allows administrators to limit the amount of QMF tracing diagnostics by QMF module name. The global variable allows up to six module names to be specified.

For additional information about any of these enhancements, see the QMF Version 12 Release 1 information in the IBM Knowledge Center at:

Enhanced Editor for ISPF Editor Users

This release of Db2 QMF includes the following significant functionality and productivity improvements:

  • Assist function extended to work with procedures as well as queries, and now also provides two types of assistance:
    • Information: about a keyword or SQL identifier, such as the structure of a table or syntax of a command.
    • Alternatives: selecting a table name to replace it with another table belonging to that owner, or selecting an SQL keyword shows other keywords of a similar type.
  • More screen space is available for editing queries and procedures, while still maintaining the ability to see a preview of your query results including the ability to drill down on a preview row displaying it vertically. With an integrated list capability, you can also quickly browse your QMF objects and data tables including drilling down to individual row values.
  • With better adherence to ISPF Editor conventions, ISPF users can adhere to ISPF standards when editing QMF objects. You can customize function keys to your own preferences using ISPF KEYS; navigate query previews and object lists using standard ISPF lists; and work with your QMF objects and data in a style more compatible with the ISPF Editor.