Primary Key

Primary Key

• One or more fields (columns) whose value or values uniquely identify each record in a table. A primary key does not allow Null values and must always have a unique value. A primary key is used to relate a table to foreign keys in other tables.

• NOTE:

You do not have to define a primary key, but it's usually a good idea. If you don't define a primary key, Microsoft Access asks you if you would like to create one when you save the table.

• For our tutorial, make the Soc Sec # field the primary key, meaning that every student has a social security number and no 2 are the same.