Message-ID: <4DE69D92.5040407@consistentstate.com>
Date: Wed, 01 Jun 2011 14:14:10 -0600
From: CS DBA <cs_dba@consistentstate.com>
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To: pgsql-performance@postgresql.org
Subject: Problem query
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Hi All;

We have a table with approx 200 columns. about a dozen columns are text 
data types and the rest are a mix of integers , bigint's and double 
precision types.

The table has about 25million rows.


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 )

I've tried to split the query up but made little progress, pri_num and  
tds_cx_ind are bigint's and  cxs_ind_2 is an integer

The table has an index on all 3 columns (3 separate indexes)

Anyone have any thoughts on tuning this query?


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