Joining Tables or Database Records › Joining Tables

Joining Tables

You can join tables that share a column of common values. For example, you can join:

• Two or more different tables.
• A table to itself when one column contains similar values to another column. For example, table EMP contains a column of manager IDs. You would join table EMP to itself to determine the name of an employee's manager.

Both of these topics are described below. This chapter also describes a method to translate a nested SELECT that retrieves more than one value into a SELECT statement that is a join operation.