From: Jim C. Nasby <jnasby@pervasive.com>
To: Sriram Dandapani <sdandapani@counterpane.com>
Cc: Pgsql-Performance (E-mail) <pgsql-performance@postgresql.org>
Subject: Re: planner not using index for like operator
Date: Tue, 25 Apr 2006 13:24:45 -0500
Message-ID: <20060425182444.GK97354@pervasive.com> (raw)
In-Reply-To: <6992E470F12A444BB787B5C937B9D4DF0406B241@ca-mail1.cis.local>
References: <6992E470F12A444BB787B5C937B9D4DF0406B241@ca-mail1.cis.local>
On Tue, Apr 25, 2006 at 10:08:02AM -0700, Sriram Dandapani wrote:
Here's the key:
> " Filter: ((col1)::text ~~ '172.%'::text)"
In order to do a like comparison, it has to convert col1 (which I'm
guessing is of type 'inet') to text, so there's no way it can use an
index on col1 (maybe a function index, but that's a different story).
Is there some reason you're not doing
WHERE col1 <<= '172/8'::inet
?
--
Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
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To: pgsql-performance@postgresql.org
Cc: jnasby@pervasive.com, sdandapani@counterpane.com
Subject: Re: planner not using index for like operator
In-Reply-To: <20060425182444.GK97354@pervasive.com>
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