Re: Bogus nestloop rows estimate in 8.4.7

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marti Raudsepp <marti@juffo.org>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2012-05-28T17:56:55Z
Lists: pgsql-hackers
Marti Raudsepp <marti@juffo.org> writes:
> This bug isn't causing me any immediate problems -- the plan works out
> well regardless -- but PostgreSQL 8.4.7 is somehow overestimating the
> number of rows coming from a nestloop join, when joining 2 large
> partitioned tables.

This sounds familiar, but a quick trawl through the commit logs didn't
immediately turn up any related-looking patches.  Can you put together
a self-contained test case?

Also, what do you have constraint_exclusion set to?

			regards, tom lane