Integrity Rules and Constraints

Enterprise Constraints

Enterprise constraints – sometimes referred to as semantic constraints – are additional rules specified by users or database administrators and can be based on multiple tables.

Here are some examples.

• A class can have a maximum of 30 students.
• A teacher can teach a maximum of four classes per semester.
• An employee cannot take part in more than five projects.
• The salary of an employee cannot exceed the salary of the employee's manager.