From: pgsql-performance-owner@postgresql.org [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of David Osborne Sent: Tuesday, November 10, 2015 12:32 PM To: Tom Lane <tgl@sss.pgh.pa.us> Cc: pgsql-performance@postgresql.org Subject: Re: [PERFORM] Slow 3 Table Join with v bad row estimate
Ok - wow.
Adding that index, I get the same estimate of 1 row, but a runtime of ~450ms. A 23000ms improvement.
This is great. So as a general rule of thumb, if I see a Join Filter removing an excessive number of rows, I can check if that condition can be added to an index from the same table which is already being scanned.
Thanks for this!
David,
I believe the plan you are posting is the old plan.
Could you please post explain analyze with the index that Tom suggested?