On Tue, Nov 20, 2012 at 8:38 PM, Craig Ringer <craig@xxxxxxxxxxxxxxx> wrote: > On 11/21/2012 12:06 AM, Claudio Freire wrote: >> I meant for postgres to do automatically. Rewriting as a join wouldn't >> work as an optimization fence the way we're used to, but pushing >> constraints upwards can only help (especially if highly selective). > Because people are now used to using CTEs as query hints, it'd probably > cause performance regressions in working queries. Perhaps more > importantly, Pg would have to prove that doing so didn't change queries > that invoked functions with side-effects to avoid changing the results > of currently valid queries. Fair point. Will look into it a bit. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
