Hi,

I wrote a script in qurey a list from two related (PK--FK) tables.
I wanted to qurey two catelogues:
1.Exist in one table as PK but not exist in the other table;
2.Exist in one table as PK and also in the other tabls as FK;
Both 1 & 2 have to satisfy condition A&B;

There exist this logical "OR" to pursue the qurey.eg.

where
conditionA
and conditionB
and SSN not in
(selct...)

or SSN in
(Select...)

I wonder by doing this am I right in the logics? Is there any better solutions?

thanks a lot!

Use OUTER JOIN , which will give the records which are in both the tables and which are in table 1 and not in table 2. syntax you can check in any book.