Re: Shouldn't the planner have a higher cost for reverse index scans? - Mailing list pgsql-performance

From Josh Berkus
Subject Re: Shouldn't the planner have a higher cost for reverse index scans?
Date
Msg-id 49DF8603.3000006@agliodbs.com
Whole thread Raw
In response to Re: Shouldn't the planner have a higher cost for reverse index scans?  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Shouldn't the planner have a higher cost for reverse index scans?  (Lists <lists@on-track.ca>)
List pgsql-performance
Tom,

> Right, because they do.  If you think otherwise, demonstrate it.
> (bonnie tests approximating a reverse seqscan are not relevant
> to the performance of indexscans.)

Working on it.  I *think* I've seen this issue in the field, which is
why I brought it up in the first place, but getting a good test case is,
of course, difficult.


--
Josh Berkus
PostgreSQL Experts Inc.
www.pgexperts.com

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