QMF Intercept

The QMF Intercept program, ANLQMF, is a condensed version of ANLSQLPA.

The QMF Intercept program manages single SQL statements under QMF and has minimal reporting requirements.

Db2 SQL Performance Analyzer interfaces with QMF by using the QMF governor exit and contains customized code that is designed for optimum performance with minimal elapsed time. Among the performance features is the elimination of virtually all I/Os to disk by replacing them with memory resident cache.

A PL/I environment is required to run the Db2 SQL Performance Analyzer cost components. That environment is set up once, upon entry into QMF. It remains ready for the processing of each query until QMF ends, which eliminates the constant processor usage of re-initializing the PL/I environment.

All nonessential code was removed from the load module, and the source code for the exit interface is provided so you can hard code the parameters that describe the environment into the exit. Hard coding the parameters avoids reading them in for each operation.

Generally, the QMF Intercept program is installed with options that show costs for only those SQL statements that exceed the guidelines that are defined in the configuration parameters. Db2 SQL Performance Analyzer runs in the background and only displays information if your queries are resource-intensive.