On Wed, 24 Sep 2014 09:04:21 -0700
Daniel Lenski <dlen...@gmail.com> wrote:
> If I include the primary key of a table in my GROUP BY clause, PG 9.3
> allows me to refer to other columns of that table without explicit GROUP BY:
>
> Why doesn't the same thing work with a non-NULL unique constraint?
At first sight, primary key means no grouping at all, as there are no
duplicated A.primary_key values:
SELECT A.document
FROM A
GROUP BY A.primary_key
is the same as
SELECT A.document
FROM A
--
Alberto Cabello Sánchez
<albe...@unex.es>
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
