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Database Management SystemCompute the closure of the following set F of functional dependencies for relation schema: R = (A, B, C, D, E). A → BC, CD → E, B → D, E → A List the candidate keys for R.20195mDatabase Management SystemFor relation R(A,B,C,D,E) functional dependencies are given as follows: * A \rightarrow BC * CD \rightarrow E * B \rightarrow D Find candidate keys.20254mDatabase Management SystemYou are given the following set F of functional dependencies for a relation: R(A, B, C, D, E, F): F = {ABC → D, ABD → E, CD → F, CDF → B, BF → D} (i) Find all keys of R based on these functional dependencies. (ii) Is this relation in Boyce-Codd normal form? Is it 3NF? Explain your answer. (iii) Can the set F be simplified (by removing functional dependencies or by removing attributes from the left-hand side of functional dependencies) without changing the closure of F (i.e. F+)?20199mDatabase Management SystemConsider the universal relation R = \{A, B, C, D, E, F, G, H, I\} and the set of functional dependencies F = \{\{A, B\} \rightarrow \{C\}, \{A\} \rightarrow \{D, E\}, \{B\} \rightarrow \{F\}, \{F\} \rightarrow \{G, H\}, \{D\} \rightarrow \{I, J\}\} What is the key for R? Decompose R into 2NF, then 3NF relations.201814m
PreviousWhich of the following is true? (i) Every relation in 3NF is also in BCNF (ii) A relation R is in 3NF if very non-prime attribute of R is fully functionally dependent on every key of R (iii) Every relation in BCNF is also in 3NF (iv) No relation can be in both BCNF and 3NFNextGiven the Students' relation as shown below: | StudentID | StudentName | StudentE-mail | StudentAge | CPI | |---|---|---|---|---| | 2345 | Shankar | shankar@math | X | 9.4 | | 1287 | Swati | swati@ee | 19 | 9.5 | | 7853 | Shankar | shankar@cse | 19 | 9.4 | | 9876 | Swati | swati@mech | 18 | 9.3 | | 8765 | Ganesh | ganesh@civil | 19 | 8.7 | For (StudentName, StudentAge) to be the key for this instance, the value X should not be equal to: (i) 18 (ii) 19 (iii) 15 (iv) 20