Re: [Help]How to translate from Algebra->SQL and viceverse?
Date: Thu, 9 Nov 2000 01:40:13 -0800
Message-ID: <t0ks96armtmpa9_at_corp.supernews.com>
"macefindu" <changth9_at_hotmail.com> wrote in message news:20001108.235408.338888228.818_at_jedi.200.41.96.2...
> I was wondering why do we must learn Algebra if it cant handle all SQL's
> operators(ie: group by ... having ...). Just take a look at the demos
> *.sql that came with Oracle, most of them contain codes that easily
> exceed 20 select in one query!
I think the GROUP BY and HAVING clauses, like ORDER BY, were added for grubby real-world purposes like creating reports. I don't think ordering is supposed to matter in the relational model.
> The only one reason that came out of my mind was "to exercise our brain muscles".
Just wait until your prof tells you how SQL was supposed to be for
end users! Do a search on "Reisner" within this page:
<http://www.mcjones.org/System_R/SQL_Reunion_95/sqlr95-System.html>
--
Joe Foster <mailto:jfoster_at_ricochet.net> Got Thetans? <http://www.xenu.net/>
WARNING: I cannot be held responsible for the above They're coming to
because my cats have apparently learned to type. take me away, ha ha!
Received on Thu Nov 09 2000 - 10:40:13 CET