Explain process

The Explain process performs several checks and activities when it runs.

Explain checks to make sure that all necessary tables are accessible.

If all necessary tables are accessible, Explain reads the first input command. The command is checked for validity, and one of the main processes is started.

Each input specification produces a complete report. Each report can consist of several pages.

If LEVEL=SUMmary is in effect, information for the current SQL statement is shown only in the summary page.

At normal completion of Explain, the last page shows a listing of all the input specifications with prefixed report numbers. You can use this page as a table of contents.