Consider a relation, R (A, B, C, D, E) with the given functional dependencies; A → B, B → DE and D → C. What is the closure (E)?Question 2Select one:a.E+ = DECb.E+ = DEc.E+ = BEd.E+ = E
Question
Consider a relation, R (A, B, C, D, E) with the given functional dependencies; A → B, B → DE and D → C. What is the closure (E)?Question 2Select one:a.E+ = DECb.E+ = DEc.E+ = BEd.E+ = E
Solution
To find the closure of E, we need to determine all the attributes that can be functionally determined by E.
Given the functional dependencies A → B, B → DE, and D → C, we can use these dependencies to find the closure of E.
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Start with E and add it to the closure set: E+ = E.
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Look for functional dependencies where the left side contains attributes already in the closure set. In this case, we have B → DE. Since B is already in the closure set, we can add D and E to the closure set: E+ = DE.
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Continue looking for functional dependencies where the left side contains attributes already in the closure set. We have D → C. Since D is already in the closure set, we can add C to the closure set: E+ = DEC.
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There are no more functional dependencies to consider, so the closure of E is DEC.
Therefore, the correct answer is E+ = DEC.
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