pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ioana Danes <ioanasoftware@yahoo.ca>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query plan issue when upgrading to postgres 8.14 (from
Date: Thu, 27 Jul 2006 18:22:05 -0400
Message-ID: <13633.1154038925@sss.pgh.pa.us> (raw)
In-Reply-To: <20060727185507.9604.qmail@web55902.mail.re3.yahoo.com>
References: <20060727185507.9604.qmail@web55902.mail.re3.yahoo.com>

Ioana Danes <ioanasoftware@yahoo.ca> writes:
>   Does anyone now what the problem is with the following select when  upgrading to postgresql 8.1.4 the query plan does not use the indexes  as in postgresql 8.0.3.
  
The planner doesn't have enough information about the correlation
between testtype and testid to guess that the index-driven max()
optimization doesn't work well in this case.  But I see you've
already found the solution ...

			regards, tom lane



view thread (6+ messages)

Message-ID: <13633.1154038925@sss.pgh.pa.us>
Permalink:  ../13633.1154038925@sss.pgh.pa.us/
Also on:    postgresql.org/message-id/13633.1154038925@sss.pgh.pa.us

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-performance@postgresql.org
  Cc: tgl@sss.pgh.pa.us, ioanasoftware@yahoo.ca
  Subject: Re: Query plan issue when upgrading to postgres 8.14 (from
  In-Reply-To: <13633.1154038925@sss.pgh.pa.us>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox