Referential Integrity

Question 1

What is referential integrity?

Answer 1

Referential integrity is feature in the database application that makes sure that a record exists in each table that has to have a primary key pointing to it.

Question 2

What is a example of a use of referential integrity?

Answer 2

One example is when an employee may have an employee number as their primary key that point to their salary in the pay table, and to their address in the address table.

This is where referential integrity comes in. If the primary key does not point to an entry in the salary table, then the database is broken.