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On Wed, 1 Dec 2004 17:59:11 -0800, "Mikito Harakiri"
<mikharakiri_at_iahu.com> wrote:
>> >Suppose we have one column relation which is essentially a set of
>intervals:
>> >
>> >{[1,2], [3,5], [4,7]}
>> >
>> >and I want to project away the interval column and calculate aggregated
>> >value of SUM(1). What the result there would be? 3? 2? 7?
>BTW, shouldn't you also
>introduce user-defined aggregate SUM on the intervals?
Yes.
>In my case, however, the column expression is a constant equal to 1, so that
>the SUM has to be a number.
Ok I misunderstood you.
I that case Sum(1) would be equivalent to Count(R) and the result would be 3.
Regards Received on Thu Dec 02 2004 - 05:52:48 CST