From: Guy Fraser <guy@incentre.net>
To: Jodi Kanter <jkanter@virginia.edu>
Cc: Postgres SQL List <pgsql-sql@postgresql.org>
Subject: Re: picking max from list
Date: Wed, 10 Dec 2003 16:11:10 -0700
Message-ID: <3FD7A80E.4000208@incentre.net> (raw)
In-Reply-To: <3FD783F6.6030801@virginia.edu>
References: <3FD783F6.6030801@virginia.edu>
select group,rd_pk
from (select ...) as your_query,
(select max(run) as max_run,rd_pk as rd
from (select ...) as your_query) as max_rd
where rd = rd_pk
and max_run = run;
I dont know if you call that one query but it should work.
There may be more elegant solutions, but I havn't had a chance to read
up on the new join types.
Good luck
Jodi Kanter wrote:
> I have a query that produces results similar to this:
>
> run# rd_pk group#
> 0 9209 5
> 1 9209 8
> 0 9520 2
> 1 9520 5
> 0 9520 etc....
> 0 8652
> 1 8652
> 2 8652
> 0 8895
> 1 8894
>
> Ultimately I want to know the group number for EACH rd_pk with the
> highest run number. Can this be done in one query? Or will I need to
> code with a loop?
> Thanks
> Jodi
--
Guy Fraser
Network Administrator
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Cc: guy@incentre.net, jkanter@virginia.edu
Subject: Re: picking max from list
In-Reply-To: <3FD7A80E.4000208@incentre.net>
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