From: Jim Nasby <Jim.Nasby@BlueTreble.com>
To: Artūras Lapinskas <arturaslape@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: postgres performance list <pgsql-performance@postgresql.org>
Subject: Re: Index order ignored after `is null` in query
Date: Fri, 14 Nov 2014 20:12:32 -0600
Message-ID: <5466B690.5000705@BlueTreble.com> (raw)
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On 11/7/14, 5:14 AM, Artūras Lapinskas wrote:
> thanks for your time and answer. Not treating IS NULL as equality operator definitely helps me to make more sense out of previous explains.
You can also try creating a partial index WHERE b IS NULL. WHERE b IS NOT NULL can also sometimes be useful, though for different reasons.
--
Jim Nasby, Data Architect, Blue Treble Consulting
Data in Trouble? Get it in Treble! http://BlueTreble.com
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To: pgsql-performance@postgresql.org
Cc: Jim.Nasby@BlueTreble.com, arturaslape@gmail.com, tgl@sss.pgh.pa.us
Subject: Re: Index order ignored after `is null` in query
In-Reply-To: <5466B690.5000705@BlueTreble.com>
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