Some elements of database quality Referential integrity is the system of rules that Microsoft Access 2000 uses to be sure the relationships between records in related tables are valid.
Referential integrity ensures that changes made in one datatable are reflected in a linked table.
You cannot enter a value in a foreign field of a table unless that value already exists in the primary key field of the primary table. You cannot delete a record from the primary table if matching records exist in a related table. The matching field from the primary table must be a primary keyAny value in the foreign field must already exist in the primary key field of the primary table. The related fields must have the same data type and size. To protect data in related tables from becoming disconnected, Access 2000 applies a system of rules called referential integrity .