Hi,

> I have a table with 3 columns A, B, C like:
> A, B, C
> =======
> 1, 1, A
> 1, 2, A
> 1, 3, B
> 1, 4, A
> 2, 10, A
> 2, 11, B
> 2, 12, C
> 2, 13, A
> ...
>
> Is it possible to write query, what returns:
> 1) values in column A where "value in column c, corresponding to
> _group_minimum_ value in column B" equals A => should return 1,1,A;
> 2,10,A etc.
> 2) as above but comparing max values - should return 1,4,A; 2,13,A;
> etc.

SELECT
t1.A
MIN(t1.B),
(SELECT t2.C FROM ATable t2 WHERE t2.A = t1.A and t2.B = MIN(t1.B)),
MAX(t1.B),
(SELECT t2.C FROM ATable t2 WHERE t2.A = t1.A and t2.B = MAX(t1.B))
FROM
ATable t1
GROUP BY
t1.A

This is only possible if A and B together are unique, because the sub-select
should be a singleton select. If not you can use MAX/MIN on t2.C, but that
depends on which record you want.


Regards,
Arno Brinkman
ABVisie

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