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38 lines
1.3 KiB
38 lines
1.3 KiB
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Exercise 4.59: Ben Bitdiddle has missed one
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meeting too many. Fearing that his habit of forgetting meetings could cost him
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his job, Ben decides to do something about it. He adds all the weekly meetings
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of the firm to the Microshaft data base by asserting the following:
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(meeting accounting (Monday 9am))
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(meeting administration (Monday 10am))
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(meeting computer (Wednesday 3pm))
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(meeting administration (Friday 1pm))
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Each of the above assertions is for a meeting of an entire division. Ben also
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adds an entry for the company-wide meeting that spans all the divisions. All
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of the company’s employees attend this meeting.
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(meeting whole-company (Wednesday 4pm))
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On Friday morning, Ben wants to query the data base for all the meetings that
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occur that day. What query should he use?
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Alyssa P. Hacker is unimpressed. She thinks it would be much more useful to be
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able to ask for her meetings by specifying her name. So she designs a rule
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that says that a person’s meetings include all whole-company meetings
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plus all meetings of that person’s division. Fill in the body of Alyssa’s
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rule.
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(rule (meeting-time ?person ?day-and-time)
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⟨rule-body⟩)
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Alyssa arrives at work on Wednesday morning and wonders what meetings she has
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to attend that day. Having defined the above rule, what query should she make
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to find this out?
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