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Functional dependency

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From:
William.Ampeh
Date:
April 30, 2002 15:23
Subject:
Functional dependency
Message ID:
OFF5D1A470.66DD35BC-ON85256BAB.0079C615@frb.gov
I got this problem from a friend and was wondering if anyone could help
out.

The following is a set of functional dependency for a relation R
(A,B,C,D,E,F) with  A->D, BE->CDF,  C->E,  D->B
where A->D implies A determines D or D is functionally dependent on A.

Questions:
1. Show with explanation that the functional dependency AC->F is implied by
the set.
2. Compute the closure(A,C) for the above set.
3. Is the set A,C a super key for the given relation R.

__________________

William Ampeh (x3939)
Federal Reserve Board


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