Skip to content
Related Articles

Related Articles

GATE | GATE CS 2013 | Question 54
  • Difficulty Level : Medium
  • Last Updated : 09 Oct, 2019

Relation R has eight attributes ABCDEFGH. Fields of R contain only atomic values. F = {CH -> G, A -> BC, B -> CFH, E -> A, F -> EG} is a set of functional dependencies (FDs) so that F+ is exactly the set of FDs that hold for R.

How many candidate keys does the relation R have?

(A) 3
(B) 4
(C) 5
(D) 6


Answer: (B)

Explanation: A+ is ABCEFGH which is all attributes except D.

B+ is also ABCEFGH which is all attributes except D.

E+ is also ABCEFGH which is all attributes except D.



F+ is also ABCEFGH which is all attributes except D.

So there are total 4 candidate keys AD, BD, ED and FD

Quiz of this Question

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up
Recommended Articles
Page :