Multiple validations in same field

[UTS]

I need to enter into a field either Null OR "N" OR "Pnnn" The Pnnn is a unique number between P001 and P999.



Obviously the "no duplicates" rule for Pnnn will interfere with the "N" entries. Is there a way around this?

Alternately, the operators who enter Null or "N" use one form, and the operators who enter Null or Pnnn use a different form. Is it possible to create different validation rules that are tied to the respective forms?

Cheers

[RuralGuy]

You can effectively validate this scheme in the BeforeUpdate event of a control on a Form.