I have 3 columns. [REQ Amount], [PO Amount], [INV Amount]. I want another column [Amount] to be the most relevant "amount" . At first a REQ is done for say $2. Then a PO is sent for the said REQ but gets messed up and issued for say $3, then my actual cost might be $3. Then the invoice comes in at $2. So when the invoice is paid, I want the $2 to be my most relevant expense amount.
How do I write a statement that says if INV Amount and PO Amount are Null, then REQ Amount, Else if INV Amount is Null then PO Amount, else, INV Amount?
Thoughts?