[comp.databases] Bug in distinct function in Unify

cheung@mathcs.emory.edu (Shun Yan Cheung) (03/21/91)

I think there is a bug in Unify's distinct function.
I first tried this query:

	select pnum, jnum
	from   spj
	group  by pnum, jnum
	having avg(qty) > 200;

And get the result:

	recognized query!

	pnum ,jnum
	------------
	p1   ,j4   
	p3   ,j4   
	p3   ,j5   
	p3   ,j6   
	p3   ,j7   
	p4   ,j2   
	p4   ,j4   
	p5   ,j4   
	p5   ,j5   
	p6   ,j3   
	p6   ,j4   
	p6   ,j7   


Next:

	select distinct pnum, jnum
	from   spj
	group  by pnum, jnum
	having avg(qty) > 200;

And now it does not give me any tuples.
-- 
Shun Yan Cheung     |  cheung@mathcs.emory.edu                  Internet
Emory University    |  cheung@emory.bitnet			BITNET
Dept of Math and CS |  Voice: (404) 727-3823
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