Answer:
In the database system, the constraint are basically used for enforced the referential integrity in the system more efficiently.
It maintain the data logically in the system and it basically prevent the incomplete information and data from residing the database system. Constraints are mainly represent the data columns in the table in which the rules are get enforced in the system.
There are mainly two types of constraints in the database system that are as follows:
- Key Constraints
- Foreign key constraints