please EXPLAIN ANALYZE Pavel 2010/1/5 Milan Zamazal <pdm@xxxxxxxxxxxx>: >>>>>> "PS" == Pavel Stehule <pavel.stehule@xxxxxxxxx> writes: > > PS> please, send explain result > > For ~ 10 million rows table: > > explain declare c cursor for select * from foo2 order by value; > QUERY PLAN > ---------------------------------------------------------------------- > Sort (cost=1829429.20..1854429.20 rows=9999999 width=10) > Sort Key: value > -> Seq Scan on foo2 (cost=0.00..154049.99 rows=9999999 width=10) > (3 rows) > > For ~ 1 million rows table, containing the first million rows from foo2 > (`value' column contains random integer data): > > explain declare c cursor for select * from foo order by value; > QUERY PLAN > ----------------------------------------------------------------------------------- > Index Scan using foo_value_idx on foo (cost=0.00..47604.02 rows=999999 width=10) > (1 row) > > When seqscan is disabled for the 10 million rows table: > > set enable_seqscan = off; > explain 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) > (1 row) > > Regards, > Milan Zamazal > > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
