You should not have the same data in two different tables. Seems to me that
the four fields belong in the supplier table. The supplier table should also
have a primary key field something like a SupplierNumber field that is just a
number or autonumber. Then the posnow would just need one field that contains
the appropriate supplier number data. Then you can link the two tables
together as needed to see the supplier fax number for example.
I highly recommend getting some relational database training or reading
"Database Design for Mere Mortals" by Hernandez before proceeding any further
on this database.

Signature
Jerry Whittle, Microsoft Access MVP
Light. Strong. Cheap. Pick two. Keith Bontrager - Bicycle Builder.
> I have a database with two tables named "posnow" (main design table) and
> supplier table(data sheet).
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> spent a enormous amount of time on this problem and this is my last headache
> for this database. Thanks from a amatuer at database design...