Re: Need SQL help, I'm stuck.

select * from t1 a
where c2=
(select max(c2) from t1 b
where a.c1=b.c1)

an index on c1 might be handy for this...

hth.

-paul

> Help. I seem to have a case of "brain lock" and can't figure out
>something that I should know is simple.
>
> Here is what I am trying to do. Let's say I have a table called
> T1 with columns C1, C2, C3, C4. It contains data as follows
>
> a 1 abcd dfg
> a 2 cvfr erg
> a 3 derg hbg
> b 1 cccc rth
> c 1 rdvg egt
> c 2 derf ett
>
> I want a SQL query that returns these rows
>
> a 3 derg hbg
> b 1 cccc rth
> c 2 derf ett
>
> All I can think of is
>
> SELECT C1, max(C2), C3, C4 FROM T1 GROUP BY C1;
>
> That does not work. What I really want is the values for C1, C3
> and C4 that are associated with the row containing the maximum
> value of C2 for each group of like C1 values. I don't even need
> to know what is max(C2).
>
> Can I join the table with itself somehow? See: "brain lock".
> This should not be hard.
>
>
> Thanks,
>
>
> =====
> Chris Albertson
> Home: 310-376-1029 chrisalbertson90278(at)yahoo(dot)com
> Cell: 310-990-7550
> Office: 310-336-5189 Christopher(dot)J(dot)Albertson(at)aero(dot)org
>
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