Thread

1. [PATCH] Allow star syntax in GROUP BY, as a shorthand for all table columns

   Marti Raudsepp <marti@juffo.org> — 2011-06-08T16:57:54Z

   Hi,
   
   This patch enables the syntax "GROUP BY tablename.*" in cases where
   earlier you'd get the error "field must appear in the GROUP BY clause
   or be used in an aggregate function"
   
   I've often needed to write queries like this:
     SELECT a.x, a.y, a.z, sum(b.w) FROM a JOIN b USING (a_id) GROUP BY
   a.x, a.y, a.z;
   Now this becomes:
     SELECT a.x, a.y, a.z, sum(b.w) FROM a JOIN b USING (a_id) GROUP BY a.*;
   
   The patch is so trivial that I'm wondering why it hasn't been
   implemented before. I couldn't think of any assumptions being broken
   by using row comparison instead of comparing each field separately.
   But maybe I'm missing something.
   
   If this patch looks reasonable, I guess the obvious next step is to
   expand the "a.*" reference to the table's primary key columns and fill
   in context->func_grouped_rels
   
   Regards,
   Marti
   

2. Re: [PATCH] Allow star syntax in GROUP BY, as a shorthand for all table columns

   Tom Lane <tgl@sss.pgh.pa.us> — 2011-06-08T17:22:15Z

   Marti Raudsepp <marti@juffo.org> writes:
   > This patch enables the syntax "GROUP BY tablename.*" in cases where
   > earlier you'd get the error "field must appear in the GROUP BY clause
   > or be used in an aggregate function"
   
   Is this really necessary now that we know about "GROUP BY primary key"?
   
   > The patch is so trivial that I'm wondering why it hasn't been
   > implemented before.
   
   Probably because it's a nonstandard kluge ...
   
   			regards, tom lane
   
   

3. Re: [PATCH] Allow star syntax in GROUP BY, as a shorthand for all table columns

   Marti Raudsepp <marti@juffo.org> — 2011-06-09T08:29:24Z

   On Wed, Jun 8, 2011 at 20:22, Tom Lane <tgl@sss.pgh.pa.us> wrote:
   > Is this really necessary now that we know about "GROUP BY primary key"?
   
   You're right. I was just looking for something easy to hack on and
   didn't put much thought into usefulness.
   I'll try to do better next time. :)
   
   Regards,
   Marti