Re: AW: [HACKERS] Re: Subselects open issue Nr. 5

Zeugswetter Andreas SARZ wrote:
>
> Guess what !
>
> It (Informix 9.12 and DB/2 4.1) says syntax error (at the first comma).

...like SyBase 11...

> (Even looked up the Manuals)
> Haha Hihi Hoho. I guess you beat them here Vadim+Bruce+Tom. * hear the cork
> popping ? *
>
> Andreas
>
> PS.: from the logical point of view, I think all rows from x should qualify
> for a where (a,b) not in (empty set)
> because for me NULL is not an empty set, at least it is treated as a value
> in a unique index.
> On the other hand you could argue: the whole set is NULL so a not in ()
> should filter where a not null.
> I guess no standard has thought about that so far. (Tom ?)
> Summary: I guess it is for us to decide. So I would do exactly as you said
> and return all except (NULL,NULL)

I prefer "logical point of view" and vote for Oracle-like behaviour.
BTW, it's easy to implement...

Vadim