NORMALIZATION

Question

WHICH OF THE FOLLOWING IS CORRECT IF RELATION R IS  IN 3NF

1. NO NON PRIME ATTRIBUTE OF R IS TRANSITIVELY DEPENDENT ON KEY(SUPER KEY,PRIMARY KEY,CANDIDATE KEY).

2.PRIME ATTRIBUTE OF R CAN BE  TRANSITIVELY DEPENDENT ON KEY(SUPER KEY,PRIMARY KEY,CANDIDATE KEY). 

3. A relation  R is in 3NF, if every non-prime attribute of R, is fully functionally dependent on some key of R.

4.A relation  R is in 3NF, if every non-prime attribute of R, is fully functionally dependent on every key of R.

Comments

1. NO NON PRIME ATTRIBUTE OF R IS TRANSITIVELY DEPENDENT ON KEY(SUPER KEY,PRIMARY KEY,CANDIDATE KEY).

=> False.However the relation satisfying R will not be in 3NF

2.PRIME ATTRIBUTE OF R CAN BE  TRANSITIVELY DEPENDENT ON KEY(SUPER KEY,PRIMARY KEY,CANDIDATE KEY). 

=> It can be true but relation will not be in BCNF.

3. A relation  R is in 3NF, if every non-prime attribute of R, is fully functionally dependent on some key of R.

True. If X->Y, and if Y is not prime then X has to be Super KEY

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i think third statement is wrong , it should be in 2NF......because partial dependency is elminated ...nothing is said about transitive dependency

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 Akash Kanase sir plz help

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1 is true .    

Answer 1

only OPTION – 4 is False.

every other options are correct

Answer 2

Only Option 2 and 3 are True.

Answer 3

Only Option 2 and 3 are True.