Re: Re: Need help with what I think is likely a simple query - for each distinct val, return only one record with the most recent date.

From: Reid Thompson <Reid(dot)Thompson(at)ateb(dot)com>
To:
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Re: Need help with what I think is likely a simple query - for each distinct val, return only one record with the most recent date.
Date: 2011-09-13 16:13:42
Message-ID: 1315930434.11095.108.camel@raker.ateb.com
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On Tue, 2011-09-13 at 16:39 +0200, Hannes Erven wrote:
> Reid,
>
>
> > where any one of these 3
> >
> > 1 1 2011-01-01
> > 1 1 2011-01-01
> > 1 3 2011-01-01
> >
> > or any one of these 2
> > 3 1 2011-01-05
> > 3 2 2011-01-05
> >
> > are suitable for val = 1, val = 3 respectively.
>
>
> Can you please describe in words what you are trying to accomplish? When
> I look at your data and expected output, I'd say you want this:
>
> For each distinct value of "val1", return any value of "val2" and
> the lowest value of "date".

for each distinct value of "val1', return the highest value(most recent)
of "date" and the value of "val2" associated with that date

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