The EXTRACT function

Typical uses of the EXTRACT parameter are to:

• Review which persistent messages were put to or got from a queue and whether the request was committed. This allows messages to be replayed.

• Review persistent messages that were put or got, but the request was backed out.

• Display which applications backed out rather than committed.

• Discover the volume of persistent data processed by queues, to identify the high use queues.

• Identify which applications set object attributes.

• Recreate object definitions for recovery purposes after a major failure.

When CSQ1LOGP with the EXTRACT parameter set is run against a log data set it processes all records in the data set, or all those within a specified range. Processing is as follows:

1. When a commit request is found, if the CSQCMIT ddname is present then the data is written to this data set. If the CSQBOTH ddname is present the data is also written to this data set.

2. When a backout request is found, if the CSQBACK ddname is present then the data is written to this data set. If the CSQBOTH ddname is present the data is also written to this data set.

3. When changes to objects are detected, the information is written to the data set identified by the CSQOBJS ddname.

4. When the last record has been processed, information about remaining units of work is written to the data set identified by the CSQINFLT ddname.

If you do not want to collect one or more of these classes of information, then omit the appropriate DD statements.