Consider a situation under an University Management System where Student, Department, Course, Payment, Teacher, Registration and Result Entity are available. You have to the consider these Entity(s) and relation(s) as like the below picture. Few attributes and constraints are stated with this picture. You may add/modify/drop necessary attribute and constraint, if required.
2. Use all the Constraint Properly
3. Prove all the Constraint Setting with an Error Message. You may collect message while entering values to the database.