Henrik wrote: > Ahh I had exactly 8 joins. > Following your suggestion I raised the join_collapse_limit from 8 to 10 and > the planners decision sure changed but now I have some crazy nested loops. > Maybe I have some statistics wrong? Yeah. The problematic misestimation is exactly the innermost indexscan, which is wrong by two orders of magnitude: > -> Index Scan using > tbl_file_idx on tbl_file (cost=0.01..8.66 rows=1 width=39) (actual > time=0.057..931.546 rows=2223 loops=1) > Index Cond: > ((lower((file_name)::text) ~>=~ 'index.php'::character varying) AND > (lower((file_name)::text) ~<~ 'index.phq'::character varying)) > Filter: > (lower((file_name)::text) ~~ 'index.php%'::text) This wreaks havoc on the rest of the plan. If this weren't misestimated, it wouldn't be using those nested loops. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
