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What are Primary and Composite keys, and how do I create them in Access 2007? A Primary Key is a field in a Table you designate that uniquely identifies a record and that the Primary Key designated field never contains blank values and doesn't allow duplicate data. Fore example, you can have many employees with the same first name and so you wouldn't want to assign the name field as a Primary Key field, but each employee would have a different social security number and so this would be a great example of designating this field as a Primary Key field. A Composite Key is two or more fields assigned a Primary key within a table. Where combination of both fields can't be blank or hold duplicates.
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