When used for a query, a Master/Master JoinDef selects records from two or more tables based on the common values in the join columns. While the respective join columns must share at least one common value, they need not share all values. However, only records containing common values are returned in a query.

For example, suppose two tables are joined by the Lastname column that both tables have. The Lastname column of the first table contains the names Adams, Baker, Choy, and Diaz, while the Lastname column of the second table contains the names Adams, Baruch, Choy, and Donelli. In this case, a query returns only the records in both tables that contain the names Adams and Choy.

When you create a Master/Master JoinDef, you enter the table name and whether it is a master or detail table on the JoinDef Definition frame. For more information, see How You Create a JoinDef.

In the following figure is an example of a Master/Master JoinDef on the JoinDef Definition frame.

The following figure shows the data retrieved from the JoinDef displayed in the preceding figure.