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Old 05-01-06, 01:22
krishna17 krishna17 is offline
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Red face Functional dependencies,,,,,need assistance for this homework problem urgently.....

Consider the relation R, which has attributes that hold schedules of courses and
sections at a university: R= {CourseNo, SecNo, OfferingDept, Credit-Hours,
CourseLevel, InstructorSSN, Semester, Year, Days_Hours, RoomNo, NoOfStudents}.
Suppose that the following functional dependencies hold on R:
{CourseNo} {OfferingDept, CreditHours, CourseLevel}
{CourseNo, SecNo, Semester, Year} {Days_Hours, RoomNo, NoOfStudents,
InstructorSSN}
{RoomNo, Days_Hours, Semester, Year} {InstructorSSN, CourseNo, SecNo}
a. Determine all the candidate keys for R. Show your steps.
b. Is the relation R in BCNF? If not, show all the FDs that violate the BCNF, and
explain why.
c. If R is not in BCNF, use the proper algorithm to find a lossless-join decomposition
of R (under the given FDs) into BCNF relational schemas. Show your decomposition
using a decomposition tree; for each step, indicates the functional dependency used.
Does your decomposition preserve dependencies? Motivate your answer.
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Old 05-01-06, 06:40
andrewst andrewst is offline
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What purpose would be served by having one of use do your homework for you? The idea of homework is (a) to give you practice, and (b) to give your teacher an insight into what you have learnt and what you have not. If we answer for you, neither of these aims it achieved, is it?

Now if you were to post your attempts at an answer, maybe someone could give you a hint as to whether you are going about it the right way.
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Old 05-01-06, 09:18
urquel urquel is offline
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How do you "motivate" your answer?
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Old 05-01-06, 09:36
Pat Phelan Pat Phelan is offline
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Quote:
Originally Posted by urquel
How do you "motivate" your answer?
The promise of increased salary, or the threat of whips and chains?

-PatP
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