On Tue, Oct 20, 2009 at 5:12 PM, Pavel Stehule <pavel.stehule@xxxxxxxxx> wrote: >> [ shrug... ] There are other possible reasons why the planner would >> fail to flatten a subquery, but none of them apply to the example you >> showed. And your example function *was* VOLATILE, by default. > > I checked this on 8.5 and function is evaluated more time although is immutable. > > postgres=# create or replace function foo(out a int, out b int) > returns record as $$ > begin > raise notice 'start foo'; > a := 10; b := 20; > return; > end; > $$ language plpgsql immutable; > CREATE FUNCTION > > postgres=# select (foo()).*; This is because select (func()).* is expanded to mean: select func(f1), func(f2) ... func(fn); This is a general issue with '*' because in postgres it means: 'evaluate me for each field of me', not 'return all fields of me'. I don't think our behavior in this regard is correct (afaict i'm in the minority though). merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general