Message-ID: <4DE6BD11.6060603@consistentstate.com>
Date: Wed, 01 Jun 2011 16:28:33 -0600
From: CS DBA <cs_dba@consistentstate.com>
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To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
CC: pgsql-performance@postgresql.org
Subject: Re: Problem query
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On 06/01/2011 03:38 PM, Kevin Grittner wrote:
> CS DBA<cs_dba@consistentstate.com>  wrote:
>
>> The app wants to run a query like this:
>>
>> select count(pri_num) from max_xtrv_st_t
>> where pri_num in (select max(pri_num) from max_xtrv_st_t where 1=1
>>                                  group by tds_cx_ind, cxs_ind_2)
>
> Why not something simpler?  There are a number of possibilities, and
> I don't claim this one is necessarily best (or even error free), but
> how about something like?:
>
> select count(*) from
>    (select distinct max(pri_num)
>    from max_xtrv_st_t
>    group by tds_cx_ind, cxs_ind_2) x
>
> -Kevin

I've tried a number of alternates, each one wants to do a seq scan of 
the table (including your suggestion above).


-- 
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Kevin Kempter       -       Constent State
A PostgreSQL Professional Services Company
           www.consistentstate.com
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