Question 14045 – NIC-NIELIT Scientist-B 2020
December 11, 2023
UGC NET CS 2013 June-paper-2
December 11, 2023
Question 14045 – NIC-NIELIT Scientist-B 2020
December 11, 2023
UGC NET CS 2013 June-paper-2
December 11, 2023

Database-Management-System

Question 314

What is the highest normal form of a relation R(A, B, C, D, E) with FD set?

{B → A, A → C, BC → D, AC→ BE}

A
2NF
B
3NF
C
BCNF
D
4NF
Question 314 Explanation: 
B → A
A → C
BC → D
AC → BE
B+ = BACDE
A+ = ACBED
So A & B are Candidate key.
There is no partial dependency, so in 2NF.
But in the BC → D, neither BC is key nor D is prime attribute, hence not in 3NF.
Note: Official Key given option-C is correct.
Correct Answer: B
Question 314 Explanation: 
B → A
A → C
BC → D
AC → BE
B+ = BACDE
A+ = ACBED
So A & B are Candidate key.
There is no partial dependency, so in 2NF.
But in the BC → D, neither BC is key nor D is prime attribute, hence not in 3NF.
Note: Official Key given option-C is correct.

Leave a Reply

Your email address will not be published. Required fields are marked *