We run stats with brconnect weekly:
brconnect -u / -c -f stats -t all
I'm trying to understand how some of our stats are old or stale. Where's my gap? We are running Oracle 11g and have Table Monitoring set on every table. My user_tab_modifications is tracking changes in just over 3,000 tables. I believe that when those entries surpass 50% changed, then they will be flagged for the above brconnect to update their stats. Correct?
Plus, we have our DBSTATC entries. A lot of those entries were last analyzed some 10 years ago. Does the above brconnect consider DBSTATC at all? Or do we need to regularly run the following, as well?
brconnect -u / -c -f stats -t dbstatc_tab
I've got tables that are flagged as stale, so something doesn't seem to be quite right in our best practice.
SQL> select count(*) from dba_tab_statistics
2 where owner = 'SAPR3' and stale_stats = 'YES';
COUNT(*)
----------
1681
I realize that stats last analyzed some ten years ago does not necessarily mean they are no longer good but I am curious if the weekly stats collection we are doing is sufficient. Any best practices for me to consider? Is there some kind of onetime scan I should do to check the health of all stats?