Thanks Abigail and Sue but your both right. I'm using DB2 which defines null, "0" or omitted entries as null. So all are defined by the DBMS even if they are not actually "defined". So both your solutions are correct as DB2 manages to return nulls as undefined using sues solution and Abigails works as the columns are defined.
Basically my problem is solved and I thank you for your help.
Being presumptious and presuming you're both female :-X big kiss for all your help.

j o h n i r l .

Sum day soon I'Il lern how 2 spelI (nad tYpe)

In reply to Re: Substituting '--' for Nulls by johnirl
in thread Substituting '--' for Nulls by johnirl

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