we are migrating to v9.5 and manual says we should do RUNSTATS on SYSCAT tables as "during database migration, the statistics collected for system catalog tables are not retained".

My question is should we do RUNSTATS on SYSCAT tables on regular basis as a maintanence (same as for regular application tables)? Thanks

Yes, you should do RUNSTATS on the system tables. The frequency depends on the frequency of changes to them.

Andy

Any time you make a big schema change. Also the first time you run them on catalog tables, make sure run them twice because the first time will add a large number of rows to some of the stats tables, and you have to run again to get stats on the stats tables.