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Unformatted text preview: Entity-Relationship Diagram Problems KEY
Based on the narratives, add the cardinality (one or many) symbol to each of the entity-relationship diagrams. 1. Sometimes, people finance their cars through a bank. Many, but not all, banks finance cars. Ba nk Fina nce s Car 2. BYU often offers several sections for a particular course, but a section cannot exist without a course. Co ur se Has Sectio n 3. Each student is only allowed to register for one section of a course, but there are possibly many students in the section. Stud e nt Regi ster s for Sectio n 4. A professor may teach several sections of a course, but excluding team-teaching classes, only one professor teaches each section. Profe ssor Tea che s Sectio n Based on the description above, what is the maximum cardinality between each instance of “Professor” and “Section?” a. Professor(1) – (1)Section b. Professor(m) – (1)Section c. Professor(1) – (m)Section d. Professor(m) – (m)Section ERD and Table Mapping Copyright Bonnie Anderson and BYU 1 5. An athlete may play on several teams, and each team needs at least one player. At hl ete Plays for Team Based on the description above, what is the maximum cardinality between each instance of “Athlete” and “Team?” a. Athlete(1) – (1)Team b. Athlete(m) – (1)Team c. Athlete(1) – (m)Team d. Athlete(m) – (m)Team ER Mapping Problems: Map the following diagrams to tables: 6. Po sitio n Title(P K) Salar y Has Em plo yee SSN(P K) Na me Position(Title(PK),Salary) Employee(SSN(PK),Name,Title(FK)) 7. Li neIte m Ite mNo(P K) De scriptio n Co mpri se s Invoi ce Invoi ceNo(P K) Custo merName LineItem(ItemNo(PK), Description, InvoiceNo(FK)) Invoice(InvoiceNo(PK), CustomerName) ERD and Table Mapping Copyright Bonnie Anderson and BYU 2 ...
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- Winter '11