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@yahoo.com
>   Cell:   310-990-7550
>   Office: 310-336-5189  Christopher.J.Albertson@aero.org
>
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