Hi! This post is related to the post "Performance of views" but this is another problem now.
Problem: PostgreSQL seems to not use my index. My postgres is 7.4. I started all over again and got my query really fast on one database (~40 seconds became 150 ms). BUT when trying on another db (same postgres server but with approx. 4 times as much data) it was really slow again (say 10 seconds). Then I run the EXPLAIN ANALYSE of a sub-query of my query which I realize was the problem. It seems that it does not make use of the index in the slower database!? fast db: ------------------------- -> Index Scan using testcase_b_bid_index on testcase (cost=0.00..1656.82 rows=426 width=38) (never executed)" ------------------------- slow db: ------------------------- -> Seq Scan on testcase (cost=0.00..2896.42 rows=33242 width=64) (actual time=77.027..791.014 rows=37093 loops=1)" ------------------------- rows=37093 is all of the existing rows of table testcase! (why does it say "never executed"?) Any ideas why it does not use my index??? How can I convince it to do so? /Rickard Citerar Tom Lane <[EMAIL PROTECTED]>: > Rickard =?iso-8859-1?b?U2r2c3Ry9m0=?= > <[EMAIL PROTECTED]> writes: > > I have a view that is really slow and I ca easily work around the > slowness by bypassing the view and query the real table directly. > > Let's see the exact definition of the view and EXPLAIN ANALYZE > results > for doing it both ways. Also, what PG version is this? > > regards, tom lane > ---------------------------------------------------------------------- Need cash? Click to get an emergency loan, bad credit ok http://tags.bluebottle.com/fc/CAaCMPJe8z3dVmZgRfajsIJMkopwDwDI/ ---------------------------(end of broadcast)--------------------------- TIP 7: You can help support the PostgreSQL project by donating at http://www.postgresql.org/about/donate
