Date: Thu, 27 Jun 2024 08:06:29 -0500
From: Bruno Wolff III <bruno@wolff.to>
To: Laurenz Albe <laurenz.albe@cybertec.at>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, pgsql-general@lists.postgresql.org
Subject: Re: Can any_value be used like first_value in an aggregate?
Message-ID: <20240627130629.GA1433@wolff.to>
Mail-Followup-To: Bruno Wolff III <bruno@wolff.to>,
	Laurenz Albe <laurenz.albe@cybertec.at>,
	Tom Lane <tgl@sss.pgh.pa.us>, pgsql-general@lists.postgresql.org
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On Wed, Jun 26, 2024 at 09:50:59 +0200,
  Laurenz Albe <laurenz.albe@cybertec.at> wrote:
>On Tue, 2024-06-25 at 14:11 -0500, Bruno Wolff III wrote:
>> The actual
>> use case is a set of tripplets returned from a query, where I want on
>> row for each distinct value in the first column, paired with the value
>> in the second column, for which the third column is the largest. The
>> second and third columns are effectively dependent on each other, so there
>> won't be any ambiguity.
>
>Try
>
>  SELECT DISTINCT ON (first_column)
>         first_column,
>         second_column,
>         third_column
>  FROM the_table
>  ORDER BY first_column, third_column DESC;

That approach worked for that part of the query. Thanks.