Eyal Wilde <eyal@xxxxxxxxxxxxxxxx> writes: > CREATE OR REPLACE FUNCTION test_func(STR text) > ... > perform t1.val FROM t1 WHERE > (COALESCE(rpad(t1.val, 100),'') ) like COALESCE(STR || '%','') > order by COALESCE(rpad(t1.val, 100), '') using ~<~ LIMIT 5; [ doesn't use index ] No, it doesn't. The LIKE index optimization requires the LIKE pattern to be a constant at plan time, so that the planner can extract the pattern's fixed prefix. An expression depending on a function parameter is certainly not constant. If you really need this to work, you could use EXECUTE USING so that the query is re-planned for each execution. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
