From: mark@mark.mielke.cc
To: Ibrahim Tekin <itekin@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: LIKE query on indexes
Date: Tue, 21 Feb 2006 12:40:48 -0500
Message-ID: <20060221174048.GA8108@mark.mielke.cc> (raw)
In-Reply-To: <e4dcba670602210757n2caf7c15t2a93353c9081c51f@mail.gmail.com>
References: <e4dcba670602210757n2caf7c15t2a93353c9081c51f@mail.gmail.com>
On Tue, Feb 21, 2006 at 05:57:12PM +0200, Ibrahim Tekin wrote:
> i have btree index on a text type field. i want see rows which starts with
> certain characters on that field. so i write a query like this:
> SELECT * FROM mytable WHERE myfield LIKE 'john%'
> since this condition is from start of the field, query planner should use
> index to find such elements but explain command shows me it will do a
> sequential scan.
> is this lack of a feature or i am wrong somewhere?
Is the query fast enough? How big is your table? What does explain
analyze select tell you?
Cheers,
mark
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To: pgsql-performance@postgresql.org
Cc: mark@mark.mielke.cc, itekin@gmail.com
Subject: Re: LIKE query on indexes
In-Reply-To: <20060221174048.GA8108@mark.mielke.cc>
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