cs186_fa07_mt1_sol 6

cs186_fa07_mt1_sol 6 - (e.g Mozart i[4 points A performance...

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3. Entity-Relationship Modeling a. The fol owing ER diagram models a database that might be used by Zel erbach Hal to store information about the performances it hosts. The diagram contains al the entity sets, their at ributes, and relationship sets you need to consider, but is missing lines connecting the relationships with the corresponding entities, and is missing key constraints. Also note that some entities might be weak entities, although if there are any, they are not (yet) drawn accordingly. Final y, be sure to clearly differentiate any THICK lines from thin ones! Express the fol owing constraints, by drawing on the above picture : i) [2 points] A composition is identified by both a name (e.g. Symphony in C major) and a composer
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Unformatted text preview: (e.g. Mozart). i ) [4 points] A performance may be preceded by a single lecture analyzing the works that are going to be performed. A lecture must be given by one lecturer . i i) [2 points] A performance is always conducted by one conductor . iv) [6 points] A performance includes a (positive) number of compositions . For a particular performance , each composition is performed by one ensemble (orchestra). An ensemble is comprised of a positive number of musicians . Every musician may participate in one ensemble . Name_________________________________________- 6 -Any combination al owed. -1 for each missing edge, either -1-1-1-1-1-1-1-1-2-1-1...
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