Hello

What parameters does DB2 use to perform automatic runstats? Does it collect distribution or index statistics?

Thank you!

I don't think it does, unless you have the appropriate statistics profile in place for the table.

Will automatic runstats execute without any parameters by default? runstats on table table-name?

For this you'll need the new option "SET PROFILE". The runstats generated by automatic runstats will use your pre-defined profile for each table.

What parameters will it use if I do not have pre-defined profile?

Auto runstats uses "with distribution and sampled detailed indexes all" if there is no profile set for the table

Thank you! Where can I find information about this? I don't see in DB2 manual.

I don't think this info is in the manuals. I'll see if there is a technote on this.

Automatic statistics collection

"By default, the statistics that are collected are basic table statistics with distribution information, and detailed index statistics using sampling (RUNSTATS options WITH DISTRIBUTION AND SAMPLED DETAILED INDEXES ALL). You can customize the type of statistics collected by enabling statistics profiling, which uses information about previous database activity to determine which statistics are required by the database workload."