I created a database and imported two Excel spreadsheets to create two tables. I'd like to make one of the common fields the primary key so I can query information from both tables. I opened up one of the tables in Design View, selected the field, then clicked on the key icon to add the primary key to that field. When I try and close the table, it comes up with an error window that says "Index or primary key can't contain a Null value". Anybody know what null value its talking about?

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Bob Howes
Framingham, MA

A reoccurring thought:

Rev 22:20 He which testifieth these things saith, Surely I come quickly. Amen. Even so, come, Lord Jesus.