On Wed, 26 Jul 2000, Tom Lane wrote: > Andriy I Pilipenko <[EMAIL PROTECTED]> writes: > > create function func() returns int as 'select 1' language 'sql'; > > > set enable_seqscan to 'off'; > > > explain select * from t where f = 1; > > > Index Scan using i on t (cost=0.00..2.01 rows=1 width=4) > > > explain select * from t where f = func(); > > > Seq Scan on t (cost=100000000.00..100000001.34 rows=1 width=4) > > Not a bug, because you didn't declare the function 'iscachable'. > For all the system knows, func() is like random() and will return a > different result at every row. An indexscan can't be used unless it's > safe to fold the function call down to a constant. See > http://www.postgresql.org/users-lounge/docs/7.0/postgres/sql-createfunction.htm Thank you for help. I used iscachable attribute and all are mostly ok except this: create table a (a int) create table b (b int) create function f() returns int as ' select a from a where a = (select max(b) from b) ' language 'sql' with (iscachable) select f() ERROR: replace_vars_with_subplan_refs: variable not in subplan target list Kind regards, Andriy I Pilipenko PAI1-RIPE
