Skip site navigation (1) Skip section navigation (2)

Re: Hash aggregates blowing out memory

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Mike Harding <mvh(at)ix(dot)netcom(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Hash aggregates blowing out memory
Date: 2005-02-25 22:08:22
Message-ID: 13801.1109369302@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-general
Mike Harding <mvh(at)ix(dot)netcom(dot)com> writes:
> Any way to adjust n_distinct to be more accurate?

You could try increasing the statistics target for the relevant columns.
What does pg_stats show for the "numdistinct" estimates of the columns
you are grouping over, and does that have anything to do with reality?

			regards, tom lane

In response to

pgsql-general by date

Next:From: Tom LaneDate: 2005-02-25 22:19:34
Subject: Re: Questions regarding notify processing.
Previous:From: Mike HardingDate: 2005-02-25 22:04:14
Subject: Re: Hash aggregates blowing out memory

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group