Re: Configuration Advice

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

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Arjen van der Meijden <acmmailing@tweakers.net>
Cc: Jeremy Haile <jhaile@fastmail.fm>, Adam Rich <adam.r@sbcglobal.net>, "'Bricklen Anderson'" <banderson@presinet.com>, pgsql-performance@postgresql.org
Date: 2007-01-18T22:11:37Z
Lists: pgsql-performance
Arjen van der Meijden <acmmailing@tweakers.net> writes:
> PS, In case any of the planner-hackers are reading, here are the plans 
> of the first two queries, just to see if something can be done to 
> decrease the differences between them.

Increase work_mem?  It's not taking the hash because it thinks it won't
fit in memory ...

There is a bug here, I'd say: the rowcount estimate ought to be the same
either way.  Dunno why it's not, but will look --- I see the same
misbehavior with a toy table here.

			regards, tom lane