What does A DBMS use to perform validation checks?

A Database Management System (DBMS) uses various mechanisms to perform validation checks, including data types, constraints, and triggers. Data types ensure that only appropriate types of data are entered (e.g., integers, strings). Constraints like primary keys, foreign keys, unique constraints, and check constraints enforce rules on the data. Additionally, triggers can be used to implement custom validation logic that executes automatically in response to certain database events.