pgsql_bbs table has about 15,000 rows! And almost of them are satify (topic='qna' and deleted<2) condition.
This explain result have a large cost. I want to low this query cost. Thanks for your concern :-) >> select * from pgsql_bbs where topic = 'qna' and deleted < 2 >> order by gid desc, pos asc limit 20, 0; >> >> But this query is not using index! >> >> The next is result of explain of this query: >> >> dsn=# explain select * from pgsql_bbs where topic = 'qna' and deleted < 2 >> dsn-# order by gid desc, pos asc limit 20, 0; >> NOTICE: QUERY PLAN: >> >> Limit (cost=15.71..15.71 rows=11 width=245) >> -> Sort (cost=15.71..15.71 rows=11 width=245) >> -> Index Scan using pgsql_topic_deleted on pgsql_bbs (cost=0.00..15.51 >rows=11 widt >h=245) > >It appears to be using the topic_deleted index according to this >explain output. >How many rows actually have topic='qna' and deleted<2? -- ==================================================== mailto:[EMAIL PROTECTED] http://database.sarang.net Dept of Neurosurgery, Dong-eui Medical Center ==================================================== ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
