Data integrity refers to the accuracy, consistency, and reliability of data stored in a database by enforcing constraints and validation rules.

Data integrity ensures that data remains accurate and valid throughout its lifecycle. It is enforced using:

• Primary keys (uniqueness)
• Foreign keys (referential integrity)
• Constraints (NOT NULL, CHECK, UNIQUE)
• Transactions (ACID properties)

Example Constraint for Data Integrity:

sqlCopyEditCREATE TABLE Employees (
    emp_id INT PRIMARY KEY,
    salary DECIMAL(10,2) CHECK (salary > 0)
);

This ensures that salary values cannot be negative.