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Unformatted text preview: NetID: CS411 Database Systems Spring 2009, Midterm Exam Solutions Problem 1 ( 11 points ) Misc. Concepts (1) False (2) True (3) False (4) False (5) True (6) False (7) False (8) False (9) False (10) False (11) False Problem 2 ( 16 points ) ER Model and Relational Model (a) There can be multiple solutions for this problem, depending on students’ assumptions. If the assumptions are reasonable and the ER diagram is drawn correctly based on the assumptions, we will give full credit. E-R diagram: Assumptions: 1 NetID: – The name of each series is unique, so name is a key for Series. – The name of actors/actresses is unique, so name is a key for Cast. – userID is unique, so userID is a key for Users. – Many actors/actresses can star in one series. One actor/actress can star in multiple different series. Hence, Act is many-many. – Many users can comment on one episode. One user can comment on different episodes. Hence, Comment is many-many....
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This note was uploaded on 02/17/2012 for the course CS 411 taught by Professor Winslett during the Fall '07 term at University of Illinois at Urbana–Champaign.
- Fall '07