Constraints in a database are used to ensure data accuracy, integrity, and reliability. They prevent the insertion of inaccurate or incomplete data, enforce the uniqueness of values, establish and maintain relationships between tables, and specify default or mandatory values.
Constraints contribute to query optimization, protect against unauthorized changes, and simplify database maintenance. They serve as documentation for data rules and conditions, aiding communication among stakeholders. Overall, constraints are essential for maintaining the quality and consistency of data in a database.
