The number of super keys of a relation R(A, B, C, D) with keys (A) and (B, C) is
ID: 3815748 • Letter: T
Question
The number of super keys of a relation R(A, B, C, D) with keys (A) and (B, C) is 2 10 12 All of the above None of the above A relation R Is in BCNF if R is in 3NF Is in 3NF if R is in BCNF May be in BCNF but not in BCNF May be neither in BCNF nor in 3NF All of the above Note of the above Consider the relation R(A, B, C, D, E) where it known that the only keys of R are {A, C, D} and {D, E}. Give a set of functional dependencies that will make {A, C, D} and {D, E} the only keys of R. This set should be such that if you delete any functional dependency, then the keys of B will be something other than {A, C, D} and {D, E}. Indicate all BCNF and 3NF violations for the set of functional dependencies in [a]. Decompose R as necessary into a collection of relations that are in BCNF, find all projected functional] dependencies on each of the decomposed relations of R. Decompose R as necessary into a collection of relations that are in 3_NF. find all projected functional dependencies on each of the decomposed relations of R. Consider the following definition of equivalent sets of functional dependencies on a relation; Two sets of functional dependencies F and F on a relation R are equivalent if all FD's in F follow from the ones in F. and all the FD's in F following from the ones in F.' Given a relation R(A.B.C))with the followings sets of functional dependencies:Explanation / Answer
1)(a) 2
Explain:No.of SuperKeys(A)+No.ofSuperKeys(BC) - No.of Superkeys(AB)+No.ofSuperkeys of(AB)
Ans = 23 + 2 2 - 22 + 2 ----->10
1)(b)4
2) a
3)incomplete data