What are the two integrity rules?
Ans: The two integrity rules are: Entity Integrity Rule & Referential Integrity Rule.
Entity Integrity Rule - If the attribute A of relation R is a major attribute of R then A cannot agree to take null values.
Referential Integrity Rule - In referential integrity, it is make sure that a value that appears in one relation for a given set of attributes as well appears for a particular set of attributes in another relation.