Question

    Which of the following best describes Third Normal Form (3NF) in a relational database? 

    A Every non-prime attribute is fully functionally dependent on the primary key. Correct Answer Incorrect Answer
    B All transitive dependencies are eliminated. Correct Answer Incorrect Answer
    C The relation is in 1NF and 2NF and contains no repeating groups. Correct Answer Incorrect Answer
    D The relation is in BCNF and contains no multi-valued attributes. Correct Answer Incorrect Answer
    E All non-prime attributes are directly dependent on the primary key. Correct Answer Incorrect Answer

    Solution

    Third Normal Form (3NF) in a relational database ensures that a relation is in 2NF and that there are no transitive dependencies. A transitive dependency occurs when a non-prime attribute is indirectly dependent on the primary key via another non-prime attribute. By eliminating these dependencies, 3NF reduces redundancy and ensures that the data is organized efficiently. This enhances data integrity and minimizes anomalies during database operations such as insertions, deletions, and updates. Why Other Options are Incorrect: A) Fully functionally dependent: This describes 2NF, not 3NF. C) No repeating groups: This is a requirement for 1NF, not 3NF. D) BCNF and multi-valued attributes: BCNF goes beyond 3NF by dealing with additional dependencies, but multi-valued attributes are related to 4NF. E) Directly dependent on the primary key: This is part of 2NF but does not address transitive dependencies, which 3NF eliminates.

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