Re: Why using "Group By"
Date: Thu, 13 Mar 2003 13:43:23 -0800
Message-ID: <3E70FB7B.288A_at_assist.org>
Bob Badour wrote:
> The short answer to your question is to allow inadvisable duplicate rows in
> the result or in the case of sybase to punish users for typos.
>
> If you have access to sybase (or sqlserver probably), try a query like:
>
> select a, b, count(*) from sometable group by a
>
> They seem to treat the expression as some sort of request for a cross
> product of sometable with itself just to tie up resources on the server. If
> the statement gave an error instead, one could at least point out that the
> redundancy aids compile-time error detection.
Sybase ASE 12.5:
create table mytable (
a int,
b int
)
insert into mytable values (1, 2) insert into mytable values (1, 3) insert into mytable values (2, 3)
select a, b, count(*)
from mytable
group by a
a b
----------- ----------- -----------
1 2 2 1 3 2 2 3 1
Doesn't behave as you described, though I agree it -should- error.
Larry Coon
University of California
larry_at_assist.org
and lmcoon_at_home.com
Received on Thu Mar 13 2003 - 22:43:23 CET