Re: GROUP BY or alternative means to group

On Mon, Mar 12, 2012 at 16:18:05 -0400,
Michael Gould <mgould(at)isstrucksoftware(dot)net> wrote:
>You need to include all columns that are not aggregrative columns in the group by. Even though that is the standard it is a pain to list all columns even if you don't need them

In later versions of postgres this is relaxed a bit. If you are grouping
by a primary key, you don't need to group by columns that are fixed
by that key. For example the following query is accepted in 9.1 as gameid
is a key for games and hence we don't need to also group by ga,es.title.

SELECT games.gameid, games.title
FROM games, crate
WHERE
games.gameid = crate.gameid
AND
games.contact = 'BOB'
AND
crate.touched >= current_timestamp + '4 year ago'
GROUP BY games.gameid
HAVING count(1) < 30
ORDER BY games.gameid
;