DBMS · Question 6 · Medium
DBMS question 6
Relation R(A, B, C) has the functional dependencies A → B and B → C, and A is the only candidate key. What is the highest normal form R satisfies?
- 1NF
- 3NF
- 2NF
- BCNF
Answer and explanation
Answer: C. 2NF
Explanation: The key A is a single attribute, so there is no partial dependency and R is in 2NF. But A → B → C is a transitive dependency of the non-prime attribute C on the key, so R is not in 3NF.
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