Q1. Explain the distinction between total and partial constraints.
Q2. Explain the difference between a weak and a strong entity set.
Q3. Explain the distinction between condition-defined and user-defined constraints. Which of these constraints can the system check automatically? Explain your answer
Q4. Design a database for an airline. The database must keep track of customers and their reservations, flights and their status, seat assignments on individual flights, and the schedule and routing of future flights. (Your design should include an E-R diagram, a set of relational schemas, and a list of constraints, including primary-key and foreign-key constraints.)