Monitoring Performance › Using the Compound Boolean Selection Facility Diagnostics Report

Using the Compound Boolean Selection Facility Diagnostics Report

The Compound Boolean Selection Facility Diagnostics Report can help you diagnose the efficiency of executing a SELFR command. See the CA Datacom/DB Database and System Administration Guide for full details on this report. Use the CA Dataquery Diagnostics Request panel to turn on CBS diagnostics at a terminal. Diagnostics are only collected for the first SELFR command for each table.

When to Use Compound Boolean Selection Facility Diagnostic Report

Use this report when:

• A query is running slowly. The report can display information to determine if the cause is access to CA Datacom/DB.
• A query is going to be put into a high-volume production environment. The report can determine if the access to CA Datacom/DB is suitably efficient.
• Accounting Facility reports indicate that you are experiencing an inefficient execution of SELFR commands.

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You can use this report in two ways:

• To determine whether CA Dataquery has correctly communicated the request stated in the query to the Compound Boolean Selection Facility. You can look at the WHERE: columns and can see which WITHs could not be passed to the Compound Boolean Selection Facility.
• To determine how the Compound Boolean Selection Facility performed the selection: what keys were used, what keys were not used due to INCLUDE-NIL-KEY, and whether a temporary index was needed. This can show that performance would improve if you add a key or change one to INCLUDE-NIL-KEY=YES, for example.