RDBMS CONCEPT REFERENTIAL INTEGRITY Referential Integrity is a system of rules that a DBMS uses to ensure that relationships between records in related table are valid, and that users don't accidentally delete or change related data. Conditions to set Referential Integrity: ✓ The matching field from the primary table is a primary key or has a unique index ✓ The related fields have the same data type ✓ Both tables belong to the same database When referential integrity is enforced, given rules should be followed: ✓ One can't enter a value in the foreign key field of the related table that doesn't exist in the primary key of the primary table. ✓ One can't delete a record from a primary table, if matching records exist in related table. ✓ One can't change a primary key value in the primary table, if that record has related records. For example, suppose Table B has a foreign key that points to a field in Table A. Referential integrity would prevent you from adding a ...