Topic group Related topics

Referential integrity validates and updates the data in the linked key fields of a relational database. In a relational database, a field or group of fields in one table (the child table) refers to the key of another table (the parent table). Referential integrity rules ensure that 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 two tables that both have a field that holds the customer number. The field names do not matter as long as the field types and sizes are identical.

dBASE Plus lets you establish referential integrity for any file type that supports it, such as dBASE and Paradox table types. Some SQL-server tables also offer referential integrity. See your SQL-server database documentation to determine if your table type supports referential integrity.

The way referential integrity is used depends on the way you have set up indexing for the tables in a relational database. This section assumes you are familiar with the concepts of index creation and management.