QMF Commands for Senior Mainframe Programmers

QMF is an excellent tool for mainframe programmers to increase productivity. QMF for windows a solution,we can query on multiple data sources.

Database management system implementations within a single company are no longer restricted to a single data source that is easy to administer and easy to access from a single front end application. Today, the typical database infrastructure has become very diverse, with relational database management systems from various vendors, and may also be installed on different operating systems. In addition, these RDBMSs are not the only data sources; a considerable amount of data can also be stored in hierarchical databases such as Information Management System (IMS) and Virtual Storage Access Method (VSAM).

Administering and accessing these diverse data sources can easily become a nightmare for people who need to work with them. Each database management system may provide a different user interface, and this fact alone makes end users and companies unhappy, because they must either learn different user interfaces or must invest extensively in education.

QMF provides these benefits:

  • Build new queries easily with the standard prompted query builder.
  • Use existing QMF objects stored on any server.
  • Automate DB2 query from Windows applications.
  • Integrate with Lotus 1-2-3, Excel, Lotus Approach, Access, Delphi, or many other OLE 2.0 applications.
  • Create and share QMF forms.
  • Edit DB2 data directly in the Table Editor.
  • Use the QMF for Windows GUI or a favorite application interface.
  • Edit table rows from a query result, or a row at a time.
  • Query multiple servers simultaneously.
  • Get outstanding DB2 performance and reliability.

QMF commands for Mainframe programmers:

One database per QMF user?

  • QMF has it own set of commands that are translated into SQL statements (DML and DDL). If a QMF user does a SAVE DATA, a new table is created (DDL) and the DBD control block will be briefly locked exclusively by DB2. If other users use the same database, this locking would not be possible.

How can I control number of rows returned to QMF user?

  • You can use the QMF Governor to limit the amount of data returned to a QMF user.

How can I save result set from my query?

  • Yes. You can use the SAVE DATA command to save the results of your query

What is the use of QMF export command?

  • By using the EXPORT command you can move queries or forms out to a dataset, and then, after switching to another DB2 subsystem, you can use the IMPORT command to import the queries or forms into the subsystem.

How to use QMF governor?

  • The QMF Governor is gentler because it will allow for prompting to continue, up to a cancel limit. Also the QMF Governor can cancel a request when too many rows are pulled in for reporting or too much CPU time has been used for a query, so this is the best option for QMF. Remember that the QMF Governor only works in the TSO environment, not in CICS.

How to change PF keys in QMF?

  • Yes. The PF (program function) keys can be changed. You can change the settings for active keys, create new settings for inactive keys, and change the text explanations for keys. For each panel, the PF keys can be changed for everyone, a particular user, or a group of users.

Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.