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Re: t1.col like '%t2.col%'

From: "Joshua D(dot) Drake" <jd(at)commandprompt(dot)com>
To: "Dan Kaplan" <dkaplan(at)citizenhawk(dot)com>
Cc: <pgsql-performance(at)postgresql(dot)org>
Subject: Re: t1.col like '%t2.col%'
Date: 2008-02-29 23:56:42
Message-ID: 20080229155642.20ac07be@commandprompt.com (view raw or flat)
Thread:
Lists: pgsql-performance
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On Fri, 29 Feb 2008 15:52:31 -0800
"Dan Kaplan" <dkaplan(at)citizenhawk(dot)com> wrote:

> I learned a little about pg_trgm here:
> http://www.sai.msu.su/~megera/postgres/gist/pg_trgm/README.pg_trgm
> 
> But this seems like it's for finding similarities, not substrings.
> How can I use it to speed up t1.col like '%t2.col%'?

Faster disks.

No matter what, that will seqscan. So if you want it to go faster, you
need faster hardware.

Sincerely,

Joshua D. Drake

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