From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter@eisentraut.org>
cc: pgsql-hackers <pgsql-hackers@postgresql.org>,
        "David G. Johnston" <david.g.johnston@gmail.com>,
        David Christensen <david@pgguru.net>,
        Jelte Fennema-Nio <postgres@jeltef.nl>
Subject: Re: [PATCH] GROUP BY ALL
In-reply-to: <634aca95-6db5-4beb-b18d-67e65582817f@eisentraut.org>
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Comments: In-reply-to Peter Eisentraut <peter@eisentraut.org>
	message dated "Fri, 26 Sep 2025 09:02:08 +0200"
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Date: Fri, 26 Sep 2025 10:11:55 -0400
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Peter Eisentraut <peter@eisentraut.org> writes:
> The initially proposed patch appears to have the right idea overall. 
> But it does not handle more complex cases like
>      SELECT a, SUM(b)+a FROM t1 GROUP BY ALL;

> (For explanation:  GROUP BY ALL expands to all select list entries that 
> do not contain aggregates.  So the above would expand to
>      SELECT a, SUM(b)+a FROM t1 GROUP BY a;
> which should then be rejected based on the existing rules.)

I thought I understood this definition, up till your last
comment.  What's invalid about that expanded query?

regression=# create table t1 (a int, b int);
CREATE TABLE
regression=# SELECT a, SUM(b)+a FROM t1 GROUP BY a;
 a | ?column? 
---+----------
(0 rows)


			regards, tom lane