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List:       postgresql-sql
Subject:    Re: [SQL] How To Exclude True Values
From:       Richard Broersma Jr <rabroersma () yahoo ! com>
Date:       2006-06-30 22:49:36
Message-ID: 20060630224936.41930.qmail () web31813 ! mail ! mud ! yahoo ! com
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> Also, I produced a second query using PostgreSQL:
> select a.id_i, a.ir_id, a.test, a.stamp
> from test a 
> join
> (
> select max(stamp) as mstamp, id_i
> from test
> group by id_i
> ) b
> on a.stamp = b.mstamp
> where a.test = false
> ;
> -- result
>  id_i | ir_id | test |        stamp
> ------+-------+------+---------------------
>     4 |     8 | f    | 2006-06-05 08:00:00

I found this query produced the same result.  It is a list slower than the first with my small
dataset.  but maybe it will improve for larger datasets?

select 
       t1.id_i, 
       t1.ir_id, 
       t1.test, 
       t1.stamp, 
       t1.inttest 
from   test as t1 
where t1.stamp = ( select max(T2.stamp) from test as t2 where t2.id_i = t1.id_i) 
and t1.test = 'f';

Regards,

Richard Broersma Jr.

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