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    Question

    Which of the following statements accurately describes

    Third Normal Form (3NF) in database normalization?
    A A table is in 3NF if it is in Second Normal Form (2NF) and all non-key attributes are directly dependent on the primary key, but not necessarily on the entire key. Correct Answer Incorrect Answer
    B A table is in 3NF if it is in First Normal Form (1NF) and all attributes are functionally dependent on the primary key, and there are no transitive dependencies between non-key attributes. Correct Answer Incorrect Answer
    C A table is in 3NF if it is in Second Normal Form (2NF) and has no partial dependencies of non-key attributes on any part of the primary key. Correct Answer Incorrect Answer
    D A table is in 3NF if it is in Third Normal Form (3NF) and includes a candidate key in addition to the primary key. Correct Answer Incorrect Answer
    E A table is in 3NF if it is in Fourth Normal Form (4NF) and all multi-valued dependencies are resolved. Correct Answer Incorrect Answer

    Solution

    Third Normal Form (3NF) is a level of database normalization that builds on the requirements of First Normal Form (1NF) and Second Normal Form (2NF). A table is considered to be in 3NF if it satisfies the following conditions: • It must be in 2NF: This means that the table must already be in First Normal Form (1NF) and have no partial dependencies, where non-key attributes depend on a portion of a composite primary key. • No Transitive Dependencies: All non-key attributes must be directly dependent on the primary key, not on other non-key attributes. This eliminates transitive dependencies, where a non-key attribute depends on another non-key attribute rather than on the primary key directly. By ensuring that there are no transitive dependencies, 3NF reduces redundancy and improves data integrity by ensuring that data is only stored in one place. This helps prevent anomalies and inconsistencies when updating the database.

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