Parameter using multiple Fields

Hi,

Is it possible to create a parameter for multiple fields. For example I have 10 optional fields for Vendors. FOURN1, FOURN2, FOURN3 etc.

I need to add a parameter to enter from Vendor to Vendor the same Vendor can apear in any of the fields. My idea is to create something like this:

{?A Fournisseur}   >= ({ICITEMO_V.FOURN1} or  {ICITEMO_V.FOURN2} or {ICITEMO_V.FOURN3} or {ICITEMO_V.FOURN4} ) etc

and

{?De Fournisseur} <= ({ICITEMO_V.FOURN1} or  {ICITEMO_V.FOURN2} or {ICITEMO_V.FOURN3} or {ICITEMO_V.FOURN4} ) etc

Am I on the right track ? Is this even possible ?

Thanks again,

Debbie