What is Referential Integrity?

Answer Posted / suriyaraj

Referential integrity is a database concept that ensures
that relationships between tables remain consistent. When
one table has a foreign key to another table, the concept
of referential integrity states that you may not add a
record to the table that contains the foreign key unless
there is a corresponding record in the linked table. It
also includes the techniques known as cascading update and
cascading delete, which ensure that changes made to the
linked table are reflected in the primary table.

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