Thread

Re: [HACKERS] Phantom row from aggregate in self-join in 6.5

Zeugswetter Andreas <andreas.zeugswetter@telecom.at> — 1999-07-23T08:17:27Z

> >     select t1.a, count(*) from foo t1, foo t2 group by t1.a;
> 
> Still, I must say that a row returning "0" in response to a 
> count(*) isn't at all suprising, I guess it's a matter of 
> whether or not the count(*) or the specific column being
> extracted determines the behavior.
> 
The reason this should intuitively return no rows is the group by clause.
The group by is supposed to give 1 row per group. Since there is no
group, there should be no rows returned.

Andreas