Question 11068 – Set-Theory
January 9, 2024Constraints
January 9, 2024ER-Model
| Question 5 |
In a schema with attributes A, B, C, D and E following set of functional dependencies are given
A → B A → C CD → E B → D E → A
Which of the following functional dependencies is NOT implied by the above set?
| CD → AC | |
| BD → CD | |
| BC → CD | |
| AC → BC |
Question 5 Explanation:
Apply membership test for all the functional dependencies.
Option (B):
BD → CD
BD+ = BD
i.e., BD cannot derive CD and hence is not implied.
Option (B):
BD → CD
BD+ = BD
i.e., BD cannot derive CD and hence is not implied.
Correct Answer: B
Question 5 Explanation:
Apply membership test for all the functional dependencies.
Option (B):
BD → CD
BD+ = BD
i.e., BD cannot derive CD and hence is not implied.
Option (B):
BD → CD
BD+ = BD
i.e., BD cannot derive CD and hence is not implied.