Marinos Yannikos wrote:
(what exactly does ANALYZE look at for text columns? in our case, about 7% of the rows match the index condition, so it seems that left-anchored regexp/like matches are not evaluated using the gathered most-common-value list at all)
oops, I think I gave myself the answer there. Of course the most-common-value list will not help if all the values that match the "bad" index condition exist only once, but have a common prefix...
Perhaps Postgres could sample the first few characters separately for such queries, but it's probably not worth it.
Regards, Marinos -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
