Database Management Systems - Exercises based on ER Model Concepts (Part 2)

DBMS: Exercises based on ER Model Concepts Topics discussed: A solved problem based on ER Model Concepts: 1. Consider the ER diagram in Figure. Assume that an employee may work in up to two departments or may not be assigned to any department. Assume that each department must have one and may have up to three phone numbers. Supply (min, max) constraints on this diagram. State clearly any additional assumptions you make. Under what conditions would the relationship HAS_PHONE be redundant in this example? 2. Consider the ER diagram in Figure. Assume that a course may or may not use a textbook, but that a text by definition is a book that is used in some course. A course may not use more than five books. Instructors teach from two to four courses. Supply (min, max) constraints on this diagram. State clearly any additional assumptions you make. If we add the relationship ADOPTS between INSTRUCTOR and TEXT, what (min, max) constraints would you put on it? Why? Follow Neso Academy on Instagram: @nesoacademy(https://bit.ly/2XP63OE) Contribute: http://bit.ly/3EpZgBD Memberships: https://bit.ly/2U7YSPI Discord: https://bit.ly/3HiGtJr WhatsApp: https://whatsapp.com/channel/0029Va9B1Bq4tRru0nqgtx3h Books: https://bit.ly/4cZYQil Website ► https://www.nesoacademy.org/ App ► https://play.google.com/store/apps/details?id=org.nesoacademy Facebook ► https://www.facebook.com/nesoacademy Twitter [X] ► https://x.com/nesoacademy Music: Axol x Alex Skrindo - You [NCS Release] #DBMSByNeso #DBMS #ERDiagram