From: Mario Weilguni <mweilguni@sime.com>
To: Fernan Aguero <fernan@unsam.edu.ar>
Cc: PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: efficient pattern queries (using LIKE, ~)
Date: Tue, 11 Sep 2007 21:08:37 +0200
Message-ID: <46E6E7B5.8000807@sime.com> (raw)
In-Reply-To: <20070911185442.GA38153@iib.unsam.edu.ar>
References: <20070911185442.GA38153@iib.unsam.edu.ar>
Fernan Aguero schrieb:
> Hi,
>
> I have a table containing some ~13 million rows. Queries on
> indexed fields run fast, but unanchored pattern queries on a
> text column are slooooow. Indexing the column doesn't help
> (this is already mentioned in the manual).
> http://www.postgresql.org/docs/8.2/interactive/indexes-types.html
>
> However, no alternative solution is mentioned for indexing
> and/or optimizing queries based on unanchored patterns:
> i.e. description LIKE '%kinase%'.
Maybe trigram search might help you? Never tried it myself, but it seems
to be able to handle substring searches.
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To: pgsql-performance@postgresql.org
Cc: mweilguni@sime.com, fernan@unsam.edu.ar
Subject: Re: efficient pattern queries (using LIKE, ~)
In-Reply-To: <46E6E7B5.8000807@sime.com>
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