Your task is to decide which of the entity sets are weak and which

Your task is to decide which of the entity sets are

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relationships are supporting many-one relationships, but all double rectangles and double diamonds are not shown. Your task is to decide which of the entity sets are weak, and which relationships support them. If there is a choice, prefer to use the attributes of the entity set itself in the key, and minimize the number of supporting relationships. There may be more than one reasonable answer, especially since "tour#" can have several reasonable interpretations. You should pick from the list below the one that is most reasonable. a) Stops is weak, and its key is the date and the name of the band making the tour the stop represents. b) Cities is not weak. c) Bands is weak, supported by By. d) Cities is weak, and its key is the city name and the name of the state it is In. Answer submitted: d) You have answered the question correctly. 3.
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Which of the following is necessarily true about the City and State entity sets and their relationship In? a) No two Cities In the same State can have the same name. b) No two cities can have the same name. c) No person can be the governor of two different states. d) No two States can have governors with the same name. Answer submitted: a) You have answered the question correctly.
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4. Translate the above E/R diagram to relations, using the "E/R" approach to handling ISA hierarchies. Then, identify which of the following relations is NOT in the resulting database schema.
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  • Fall '08
  • Staff
  • Entity-relationship model, E/R Diagram

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