Given the functional dependency R → (S,T) , then it is also true that R → S.
A. True
B. False
Answer: Option A
Solution (By Examveda Team)
Option1: TrueIn the given functional dependency R ? (S,T), it means that the value of R uniquely determines the values of both S and T. Therefore, it is also true that R ? S, as the value of R uniquely determines the value of S. This is a valid implication based on the given functional dependency.
Option2: False
If R ? (S,T) is true, it does not necessarily mean that R ? S is also true. The functional dependency R ? (S,T) indicates that the value of R uniquely determines both S and T, but it does not specify that R uniquely determines S alone. Therefore, it is not always true that R ? S based on the given functional dependency.
In conclusion, Option1: True is the correct answer as the given functional dependency R ? (S,T) implies that R ? S is also true.
This Question Belongs to Database >> The Relational Model And Normalization
Related Questions on The Relational Model and Normalization
A. A → B.
B. A → C.
C. A → (B,C).
D. (B,C) → A.
A. normal forms.
B. referential integrity constraints.
C. functional dependencies.
D. None of the above is correct.
A relation is in this form if it is in BCNF and has no multivalued dependencies:
A. second normal form.
B. third normal form.
C. fourth normal form.
D. domain/key normal form.
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