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Alex Filonov wrote:
> If I understand it right, pk column is a primary key in the second
> table as well.
yes
> In this case, there is no difference between not in and
> not exists.
why?
> BTW, in some cases the most efficient statment would be:
>
> select * from t1
> where t1.pk in
> (select pk from t1
> minus
> select pk from t2)
thx Received on Mon Dec 09 2002 - 15:22:54 CST