On Wed, 2003-08-20 at 14:51, Tom Lane wrote:
> Bruno Wolff III <[EMAIL PROTECTED]> writes:
> > On Wed, Aug 20, 2003 at 13:44:59 -0500,
> > Ron Johnson <[EMAIL PROTECTED]> wrote:
> >> The GROUP BY does implicit sorting, so an ORDER BY on the exact same
> >> column(s) as the GROUP BY is redundant.
>
> > That is an implementation detail, not a promise. With hashed aggregates
> > in 7.4, you might find this isn't true.
>
> s/might/will/
>From 7.3.3, where the records were randomly inserted; note how
GROUP BY acts like I described:
test1=# select f, count(*)
test1-# from t
test1-# group by f;
f | count
---+-------
1 | 3
2 | 5
4 | 4
(3 rows)
The new 7.4 attitude is *really* good to know, because, otherwise,
all our reports would break!
--
-----------------------------------------------------------------
Ron Johnson, Jr. [EMAIL PROTECTED]
Jefferson, LA USA
"Fair is where you take your cows to be judged."
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TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match
