UGC-NET NOVEMBER 2017 QUESTIONS WITH EXPLANATION
CBSE-NET NOVEMBER 2017 QUESTIONS WITH EXPLANATION
NTA-NET NOVEMBER 2017 QUESTIONS WITH EXPLANATION
Q: 9 If every non-key attribute is functionally dependent on the primary key, then the relation is in __________ .
(A) First normal form
(B) Second normal form
(C) Third normal form
(D) Fourth normal form
Answer: (B)
Explanation: Conditions for various normal forms:
- 1 NF – A relation R is in first normal form (1NF) if and only if all underlying domains contain atomic values only.
- 2 NF – A relation R is in second normal form (2NF) if and only if it is in 1NF and every non-key attribute is fully dependent on the primary key.
- 3 NF – A relation R is in third normal form (3NF) if and only if it is in 2NF and every non-key attribute is non-transitively dependent on the primary key.
- BCNF – A relation R is in Boyce-Codd normal form (BCNF) if and only if every determinant is a candidate key.
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