Re: Select groupping by one column - Mailing list pgsql-general

From Bruno Wolff III
Subject Re: Select groupping by one column
Date
Msg-id 20031218212518.GB28777@wolff.to
Whole thread Raw
In response to Select groupping by one column  (Josué Maldonado <josue@lamundial.hn>)
Responses Re: Select groupping by one column
List pgsql-general
On Thu, Dec 18, 2003 at 15:09:52 -0800,
  Josué Maldonado <josue@lamundial.hn> wrote:
> Hello list,
>
> I have a table called pedh that looks like this:
>
> REFNO    FECHA        OCNUM    PVD
> 0199    10/12/2003    5224    632
> 0199    10/12/2003    5224    632
> 1264    10/18/2003    8991    210
> 1264    10/18/2003    8991    210
> 1264    10/18/2003    8991    210
> 9093    10/20/2003    6895    520
> 9093    10/20/2003    6895    520
>
> I need to select one record groupped by column refno, I tried using this
> code:
>
> select refno, max(fecha), max(ocnum), max(pvd) from pedh

I don't see how that could work. Maybe you left off group by. But if you
did the aggreates could come from different rows, which might not be what
you want.

>
> It seems to work fine, but is there another way to get the same result
> avoing use of aggregate functions?

You might be able to use distinct on instead of aggregates.

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