I'm baffled by this one.

I'm baffled by a unexpected responce from a simple query using Oracle 7 server version 7.3.2.3.2. It's this:

Select item from tablea
where item not in (select item from tableb)
/

Gives no data found. Where

Select item from tablea
minus
select item from tableb
/

Gives some items. Further

Select a.item from tablea a
where a.item not in (select b.item from tableb b where b.item = a.item)
/

Gives the same response as the second query.

Obviously tablea and tableb both have the same definition of item. I've not been able to reproce this on other tables, just two particular ones. My only guess is there is an index being used or not that is causing the server to give the wrong responce to the first query.

Anyone?

Neil. Received on Sat Dec 20 1997 - 00:00:00 CST