(a) Amal has a large Book collection. His friends like to borrow his Books, and he needs a way to keep track of who has what. He maintains a list of friends, identified by unique FID's (Friend Identifiers) and a list of Book's, identified by BID's (Book identifiers). With each friend, he has the name, address and the all-important telephone numbers which he can call to get the Book back. With each Book, he has author name and title. Whenever a friend borrows a Book, Amal will enter that fact into his database along with the date borrowed. Whenever the Book gets returned, that fact, too, gets noted along with the date returned. Draw an ER Diagram for this database requirement and mark all constraints.

Explanation

The ER diagram shows the entities, attributes, and relationships in the database. The constraints ensure data integrity and consistency.