Re: U_SUMMARIZE: how aggregate is calculated?
From: Alfredo Novoa <alfredo_at_ncs.es>
Date: Thu, 02 Dec 2004 11:52:48 GMT
Message-ID: <41af01f4.3703453_at_news.wanadoo.es>
Date: Thu, 02 Dec 2004 11:52:48 GMT
Message-ID: <41af01f4.3703453_at_news.wanadoo.es>
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 - 12:52:48 CET