From: Madison Kelly <linux@alteeve.com>
To: pgsql-performance@postgresql.org
Cc: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: tgl@sss.pgh.pa.us
Cc: tobias@nordicbet.com
Subject: Re: Index ot being used
Date: Mon, 13 Jun 2005 13:57:31 -0400
Message-ID: <42ADC90B.4040808@alteeve.com> (raw)
In-Reply-To: <s2ad532e.099@gwmta.wicourts.gov>
References: <s2ad532e.099@gwmta.wicourts.gov>
Kevin Grittner wrote:
>>tle-bu=> \d file_info_7_display_idx
>> Index "public.file_info_7_display_idx"
>> Column | Type
>>-----------------+----------------------
>> file_type | character varying(2)
>> file_parent_dir | text
>> file_name | text
>>btree, for table "public.file_info_7"
>
>
> The index is fine, but you need to phrase the query as
>
> ... ORDER BY file_type, file_parent_dir, file_name;
>
> (Whether you use ASC or not doesn't matter.) Otherwise the planner
> won't make the connection to the sort ordering of the index.
>
> regards, tom lane
With Bruno's help I've gone back and tried just this with no luck. I've
re-written the query to include all three items in the 'ORDER BY...'
column in the same order but the sort still takes a long time and a
sequential scan is being done instead of using the index.
For what it's worth, and being somewhat of a n00b, I agree with the idea
of a smarter, more flexible planner. I guess the trade off is the added
overhead neaded versus the size of the average query.
Madison
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Madison Kelly (Digimer)
TLE-BU, The Linux Experience; Back Up
http://tle-bu.thelinuxexperience.com
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
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To: pgsql-performance@postgresql.org
Cc: linux@alteeve.com, Kevin.Grittner@wicourts.gov, tgl@sss.pgh.pa.us, tobias@nordicbet.com
Subject: Re: Index ot being used
In-Reply-To: <42ADC90B.4040808@alteeve.com>
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