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Message-ID: <c2d9e70e05033019015c554f03@mail.gmail.com>
Date: Wed, 30 Mar 2005 22:01:24 -0500
From: Jaime Casanova <systemguards@gmail.com>
Reply-To: Jaime Casanova <systemguards@gmail.com>
To: =?UTF-8?B?5p6X77+9W+mLhQ==?= <s9154083@cyut.edu.tw>
Subject: Re: A SQL Question About distinct, limit, group by, having, aggregate
Cc: pgsql-sql@postgresql.org
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On Thu, 31 Mar 2005 10:29:16 +0800, "=E6=9E=97=EF=BF=BD[=E9=8B=85" <s915408=
3@cyut.edu.tw> wrote:
> i have a little question, how to get 3 higher score student in every clas=
s.
> Data looks like as below
>=20
> problem:
> id=09=09class=09=09score
> john=09=09a=09=09100
> jenny=09=09a=09=0970
> ken=09=09a=09=0959
> mary=09=09b=09=0985
> jacky=09=09b=09=0980
> lily=09=09b=09=0970
> kevin=09=09b=09=0950
> david=09=09b=09=0930
> tina=09=09c=09=0985
> tony=09=09c=09=0980
> bare=09=09c=09=0970
> vivian=09=09c=09=0960
> eric=09=09c=09=0957
> andy=09=09c=09=0950
>=20
> result:
> id=09=09class=09=09score
> john=09=09a=09=09100
> jenny=09=09a=09=0970
> ken=09=09a=09=0959
> mary=09=09b=09=0985
> jacky=09=09b=09=0980
> lily=09=09b=09=0970
> tina=09=09c=09=0985
> tony=09=09c=09=0980
> bare=09=09c=09=0970
>=20
Actually, i don't see any difference between problem and results but maybe

select * from yourTable order by class, score desc

regards,
Jaime Casanova