Franck Routier <franck.rout...@axege.com> writes: > Le 05/04/2013 16:17, Tom Lane a écrit : >> What have you got the statistics targets set to in this database?
> Ok, the problem definitely comes from the default_statistics_target > which is obviously too high on the database. Yeah, eqjoinsel() is O(N^2) in the lengths of the MCV lists, in the worst case where there's little overlap in the list memberships. The actual cost would depend a lot on the specific column datatypes. Not sure about your report that re-analyzing with the same stats target made a significant difference. It might have been a matter of chance variation in the sampled MCV list leading to more or fewer matches. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance