Why Create Relationships?

Lesson 2 encouraged you to make separate tables for information that was not directly related. As you've learned along the way, when you create forms, queries, and reports, you can pull information from more than one table easily. But this works best when there is a well-defined relationship between the tables.

Let's say, for instance, that I had two tables containing information about my customers. One table, Customers, contained their names and addresses, and the other, Orders, contained their orders. The two tables would have a common field: Customer ID#. All records in the Orders table would correspond to a record in the Customers table. (This is called a "many-to-one" relationship because there could be many orders for one customer.)

As another example, in my kennel database, I have several tables describing my dogs and their activities. I have a table listing all the different colorings a dog can have. I could create a relationship between the Dogs table and the Coloring table, matching up each dog's coloring field with one of the accepted colors listed in the Coloring table. This would ensure that I didn't record any dog's coloring as a type that's not allowed.