Obtaining old object structure definitions and SYSCOPY records

In overtime mode, you can use the following sources for old object structure definitions, compression dictionaries, and SYSCOPY records:

• Db2 log (recommended source)

  Log Master can extract the required information from the log records that Db2 generates when you create or drop the object, and from the current Db2 catalog. The log and the Db2 catalog are maintained by Db2, which makes them more reliable than other sources. We strongly recommend that you use these Db2-maintained sources when you run in overtime mode.

  These sources can be used with either the proactive or the reactive method of obtaining structure definitions.

You can use the following methods to obtain old object structure definitions:

• With the proactive method, you obtain the structure definitions and SYSCOPY events in advance so that you have them when you need them. For more information, see Using the proactive method to obtain old object structure definitions and corresponding SYSCOPY records.

• With the reactive method, you wait until you need to access old objects before you obtain the structure definitions. The reactive method requires less preparation, but lengthens the response time when you need to retrieve data about old objects. In addition, if the corresponding SYSCOPY events are not stored in the repository, other methods, such as REPOS UPDATE with INCLUDE SYSCOPY START option or IMAGECOPY statements, might be required for Log Master to correctly process the logs for old objects.

  With the reactive method:

  • You have not maintained old object structure definitions in the Repository.

  • You can obtain old object structure definitions and SYSCOPY records from the Db2 log. See Using the reactive method (with the Db2 log) to obtain old object structure definitions and SYSCOPY records.

When you read input from logical log files, you do not need to perform a separate step to obtain old object structure definitions. For more information, see Log scan input sources.

This section contains the following topics:

• Using the proactive method to obtain old object structure definitions and corresponding SYSCOPY records
• Using the reactive method (with the Db2 log) to obtain old object structure definitions and SYSCOPY records