2010/1/5 Milan Zamazal <pdm@xxxxxxxxxxxx>: >>>>>> "PS" == Pavel Stehule <pavel.stehule@xxxxxxxxx> writes: > > PS> please EXPLAIN ANALYZE Pavel > > I see, I'm sorry. Here are the results: Have you original values random_page_cost and seq_page_cost in postgres.conf? it is strange. Pavel > > set enable_seqscan = on; > explain analyze declare c cursor for select * from foo2 order by value; > QUERY PLAN > ------------------------------------------------------------------------------------------------------------------------- > Sort (cost=1829429.20..1854429.20 rows=9999999 width=10) (actual time=43432.727..49303.902 rows=9999999 loops=1) > Sort Key: value > Sort Method: external merge Disk: 204208kB > -> Seq Scan on foo2 (cost=0.00..154049.99 rows=9999999 width=10) (actual time=0.058..1775.928 rows=9999999 loops=1) > Total runtime: 53693.012 ms > (5 rows) > > set enable_seqscan = off; > explain analyze declare c cursor for select * from foo2 order by value; > > QUERY PLAN > --------------------------------------------------------------------------------------------------------------------------------------------- > Index Scan using foo2_value_idx on foo2 (cost=0.00..32220140.73 rows=9999999 width=10) (actual time=0.225..55055.583 rows=9999999 loops=1) > Total runtime: 56394.283 ms > (2 rows) > > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
