made easy test series

Question

i think in this ques BD->E also voilates 3NF plz correct me if i am wrong

Comments

But B along with D determines E which is prime so dont it be also a prime attribute?

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But how A->B is violating??
A is prime attribue

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but it is not a super key

in 3NF x->y

holds only if xis a super key or y is a prime attribute.

Answer 1

A relational is in 3NF if there is no transitive dependency

AT above only A⇢B having Transitive dependency.so only 1FD violate 3NF

Comments

thnx bro..

Answer 2

 A table is in 3NF if and only if, for each of its functional dependencies X → A, at least one of the following conditions holds:

• X contains A (that is, X → A is trivial functional dependency), or
• X is a superkey or
• A is a prime attribute

In BD->E, E is a prime attribute hence it does not violate 3nf defintion.

Answer 3

x-----y is in 3NF . X is key or y is prime attribute