Re: NOT IN is very inefficient

IMHO, it is correct.

If you filter 'B.i is null' it's the same thing as using your first query with an empty table B.

if table A = {1,2,3 and B = {}

 select A.i, B.i from A, B where A.i *= B.i

gives the correct answer

   A.i B.i

    1  (null)
    2  (null)
    3  (null)

Geert 'Darling' Van Damme

James Cribb wrote in message <6vma5n$qnb$1_at_the-fly.zip.com.au>...
>| Table A (i int) has values 1, 2, 3.
>| Table B (i int) has values 1, 3
>|
>| select A.i, B.i from A, B where A.i *= B.i
>|
>| ("*=" means "left outer join") returns
>|

 ...
>| Filtering "B.i is null" returns all three rows of A.
>
>does produce the unexpected result
>
> A.i B.i
> 1 (null)
> 2 (null)
> 3 (null)
>
>| Is this a bug in SQL Anywhere?
>
Received on Mon Oct 12 1998 - 00:00:00 CDT