Re: LIKE query on indexes - Mailing list pgsql-performance

From mark@mark.mielke.cc
Subject Re: LIKE query on indexes
Date
Msg-id 20060221174048.GA8108@mark.mielke.cc
Whole thread Raw
In response to LIKE query on indexes  ("Ibrahim Tekin" <itekin@gmail.com>)
Responses Re: LIKE query on indexes  ("Ibrahim Tekin" <itekin@gmail.com>)
List pgsql-performance
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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