Add, edit, or delete referential integrity rules for the currently selected table. To use this dialog box you must first either login to a database or, in dBASE Plus Navigator, select a directory containing tables (such as DBF and DB) that support referential integrity.

Referential integrity means that a field or group of fields in one table (the child table) must refer to the key of another table (the parent table). Only values that exist in the parent table’s key are valid values for the specified fields of the child table.

You can establish referential integrity only between like fields that contain matching values. For example, you can establish referential integrity between the sample Customer.db and Orders.db tables on their Customer No fields. The field names don’t matter as long as the field types and sizes are identical.

Dialog box options

 

New

Displays the Define Referential Integrity Rule dialog box for constructing relationships between fields of related tables in the current database.

Modify

Displays the Define Referential Integrity Rule dialog box for modifying existing relationships between fields of related tables. You must be able to obtain exclusive access to all tables involved in the referential integrity when you modify it.

Drop

Remove the highlighted referential integrity rule.

How to get there: Choose File|Database Administration and in the Database Administration dialog box click Referential Integrity.