Transactions
August 29, 2024Transactions
August 29, 2024Database-Management-System
|
Question 608
|
A relation R={A, B, C, D, E, F} is given with following set of functional dependencies : F =, {A →B,AD →C,B→F,A →E}
Which of the following is candidate key?
Which of the following is candidate key?
|
A
|
|
|
AC
|
|
|
AD
|
|
|
None of these
|
Question 608 Explanation:
Here, Attribute A and D are not present in the right hand side of any production so every key should include AD to be a candidate key.
Step-1: Check whether AD could be a candidate key or not.
(AD) + = {A,D,C,B,F,E}
Step-2: AD can uniquely identifies each attribute. So, AD is the candidate key for given relation.
Step-1: Check whether AD could be a candidate key or not.
(AD) + = {A,D,C,B,F,E}
Step-2: AD can uniquely identifies each attribute. So, AD is the candidate key for given relation.
Correct Answer: C
Question 608 Explanation:
Here, Attribute A and D are not present in the right hand side of any production so every key should include AD to be a candidate key.
Step-1: Check whether AD could be a candidate key or not.
(AD) + = {A,D,C,B,F,E}
Step-2: AD can uniquely identifies each attribute. So, AD is the candidate key for given relation.
Step-1: Check whether AD could be a candidate key or not.
(AD) + = {A,D,C,B,F,E}
Step-2: AD can uniquely identifies each attribute. So, AD is the candidate key for given relation.