On Tue, 2007-02-13 at 21:44 -0500, Tom Lane wrote: > Rajarshi Guha <rguha@xxxxxxxxxxx> writes: > > However the clause: > > dock.target = '1YC1' and > > dock.dockid = dockscore_plp.id > > reduces the number of rows from 4.6M to 96K. > > The planner seems to be estimating about ten times that many. Perhaps > increasing the statistics target for dock.target would help? My original message had a typo: I expected that it should ~ 960K, so postgres is working as expected. However increasing the statistics target for dock.target did lead to an improvement in performance. Could this be because dock.target has only 5 unique values? So though the table has ~4.6M rows, each set of ~960K rows for dock.dockid is associated with a single value of dock.target. Thanks, ------------------------------------------------------------------- Rajarshi Guha <rguha@xxxxxxxxxxx> GPG Fingerprint: 0CCA 8EE2 2EEB 25E2 AB04 06F7 1BB9 E634 9B87 56EE ------------------------------------------------------------------- All great ideas are controversial, or have been at one time.
