On Thursday, March 10, 2011 05:26:00 PM Julius Tuskenis wrote: > 3) As STABLE function should be executed once for every different set of > parameters Thats not true. Thats not what any of the volatility information (like STABLE, IMMUTABLE, VOLATILE) does. See http://www.postgresql.org/docs/current/interactive/xfunc-volatility.html It *does* change how often a function is executed though. I.e. SELECT g.i, some_stable_func(1) FROM generate_series(1, 1000) g(i) will call some_stable_func only once because it can determine all the parameters beforehand. Andres -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance