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Re: a change of query - Mailing list pgsql-sql

From Chad Thompson
Subject Re: a change of query
Date
Msg-id 06eb01c2dd1e$ee5488b0$32021aac@chad
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In response to a change of query  ("James Cooper" <jim@luckydigital.com>)
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how about
select count(distinct cp.person_id) from cluster_person cp, cluster c where cp.cluster_id = c.cluster_id and c.c_id = 1
 
Is that as fast?
Chad
----- Original Message -----
To: sql
Sent: Tuesday, February 25, 2003 3:03 PM
Subject: [SQL] a change of query

select distinct cp.person_id from cluster_person cp, cluster c where cp.cluster_id = c.cluster_id and c.c_id = 1

can this query be changed to give just the row count?( of the distinct rows )

yes: i am aware of count() but this wont count the distinct rows - I can however achive this with an nested person_id in(select... etc but that slows things down big time!!!!

the above quey gives me my resultset asap - is there a way to get just the number of rows with the same speed

My thoughts are that I could just make a plpgsql  function with a GET Diagniostics ROW_COUNT -

thoughts?

 

James

 

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