Re: Why using "Group By"
Date: Tue, 18 Mar 2003 05:16:38 GMT
Mikito Harakiri wrote:
> "oferbu" <junkbu_at_hotmail.com> wrote:
>>So if I sum all the replies by now, there is no really any need for >>the extra information added by the clause "Group by YYY, ZZZ" when the >>SQL already contains an aggregate function, right?
> Correct: nobody, suggested a reason convincing enough to justify "group by".
> Even in complicated examples like this
IIRC, didn't Chris Date have a sequence of articles with the heading GBH - Grievous Bodily Harm - in DBP&D in the last months of his "According to Date" series. The thesis was roughly that both GROUP BY and HAVING (the GB and H in GH) were unnecessary, even harmful.
I believe that this is correct - except that standard SQL requires it.
-- Jonathan Leffler #include <disclaimer.h> Email: jleffler_at_earthlink.net, jleffler_at_us.ibm.com Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/Received on Tue Mar 18 2003 - 06:16:38 CET