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+1 vote
Que- R(ABCD) and fds are { A->B ,B->C,C->A} then number of candidate key is........?

Explain please
asked in Databases by Active (3.7k points) | 45 views
IT will be 3 {AD, CD, BD}
Can you please explain??
D is the Multi value Attribute, so it will be in every CK, and From the FD's we can easily see that A, B and C defining each other.

So, CK {AD, BD, CD}.
Thanks bro
y u said d ismultivalued? if any attribute not present in fd that means that attribute is multivalued??

please exlain.

1 Answer

+1 vote
Best answer

Closure of A ,B and C give = ABC but D is missing so Candidate key will be AD ,BD,CD now we take closure of AD = ABCD , BD = ABCD , CD = ABCDso we get all attributes of Relation so AD is candidate key 

Reference :- Question number 4

answered by Loyal (6.7k points)

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