Re: [PATCH] GROUP BY ALL

David Christensen <david@pgguru.net>

From: David Christensen <david@pgguru.net>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: Peter Eisentraut <peter@eisentraut.org>, pgsql-hackers <pgsql-hackers@postgresql.org>, "David G. Johnston" <david.g.johnston@gmail.com>, Jelte Fennema-Nio <postgres@jeltef.nl>

Date: 2025-09-26T15:52:36Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Add GROUP BY ALL.
- ef38a4d9756d 19 (unreleased) landed
Refactor to avoid code duplication in transformPLAssignStmt.
- b0fb2c6aa5a4 19 (unreleased) landed
Fix missed copying of groupDistinct in transformPLAssignStmt.
- b7f6798c056a 16.11 landed
- 9ca79896aba3 15.15 landed
- 78a284b0b8d4 18.1 landed
- 7504d2be9eb4 19 (unreleased) landed
- 3fc9aa5b0233 17.7 landed
- 0be39b4b1a01 14.20 landed

On Fri, Sep 26, 2025 at 9:12 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> 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)

Agreed that this shouldn't be an error; added a similar test case to
v2 of this patch.

David