Dawid Kuroczko <[EMAIL PROTECTED]> writes: > qnex=# EXPLAIN SELECT * FROM log NATURAL JOIN useragents LIMIT 1;
> Limit (cost=15912.20..15912.31 rows=1 width=272) > -> Hash Join (cost=15912.20..5328368.96 rows=47044336 width=272) > If I set enable_hashjoin=false: > qnex=# EXPLAIN ANALYZE SELECT * FROM log NATURAL LEFT JOIN useragents LIMIT 1; > Limit (cost=0.00..3.07 rows=1 width=272) (actual time=74.214..74.216 > rows=1 loops=1) > -> Nested Loop Left Join (cost=0.00..144295895.01 rows=47044336 > width=272) (actual time=74.204..74.204 rows=1 loops=1) This is quite strange. The nestloop plan definitely should be preferred in the context of the LIMIT, considering that it has far lower estimated cost. And it is preferred in simple tests for me. It seems there must be something specific to your installation that's causing the planner to go wrong. Can you develop a self-contained test case that behaves this way for you? I recall we saw a similar complaint a month or two back, but the complainant never followed up with anything useful for tracking down the problem. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings