@ Bikram sir can you plz explain meaning of option B

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+19 votes

Which of the following is **TRUE**?

- Every relation in 3NF is also in BCNF
- A relation R is in 3NF if every non-prime attribute of R is fully functionally dependent on every key of R
- Every relation in BCNF is also in 3NF
- No relation can be in both BCNF and 3NF

0

@ Gate Ranker18 in case B) * non-prime-->non prime* dependency is possible which is not the case in 3NF(transitive dependency)

0

rajoramanoj acc to me both B and C are correct

reena_kandari it is **X-> non_prime** not **non-prime-->non prime**

+3

every non-prime attribute of R is fully functionally dependent on every key of R

it gurantee there should not be the case of * prime--->non-prime * other than

it does not say anything about **non-prime-->non prime*** , *so it can occure here which for sure does not gurantee 3NF.

+23 votes

+5

Nopes, that does not guarantee 3NF. For 3NF there **should not** be any FD X->Y such that Y-X is a non-key and X is not a super key.

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