Re: Why using "Group By"
From: Mikito Harakiri <mikharakiri_at_ywho.com>
Date: Thu, 13 Mar 2003 10:31:25 -0800
Message-ID: <Id4ca.9$wV5.27_at_news.oracle.com>
Date: Thu, 13 Mar 2003 10:31:25 -0800
Message-ID: <Id4ca.9$wV5.27_at_news.oracle.com>
"oferbu" <junkbu_at_hotmail.com> wrote in message
news:b9b409f2.0303130207.42f8ab91_at_posting.google.com...
> Why do I need to add the "Group By" in
> the following SQL:
>
> SELECT
> CUSTOMER_CITY, COUNT(*)
> FROM
> CUSTOMER_TABLE
>
> Isn't it clear that I want to get the number of rows per city, so why
> is it necessary to add:
>
> GROUP BY
> CUSTOMER_CITY
>
> I mean to say that those added lines didn't give more information, and
> any resonable person (or a good sql parser...) could have understand
> what I really want at the first sql.
select max(sum(sal)) from emp
is not the same as
select max(sum(sal)) from emp