New 55% Off on All Courses - Enroll Now! Click Here

    Question

    Which of the following is the main objective of the

    3rd Normal Form (3NF) in database normalization?
    A Remove partial dependencies in a relation Correct Answer Incorrect Answer
    B Eliminate duplicate data and achieve minimal redundancy Correct Answer Incorrect Answer
    C Ensure that all non-key attributes depend only on the primary key Correct Answer Incorrect Answer
    D Guarantee that every relation contains a candidate key. Correct Answer Incorrect Answer
    E Ensure that no two rows have identical data across all columns. Correct Answer Incorrect Answer

    Solution

    The Third Normal Form (3NF) eliminates transitive dependencies, ensuring that every non-key attribute is directly dependent on the primary key and not on another non-key attribute. This simplifies data integrity and reduces redundancy. For instance, in a table with attributes EmployeeID, DepartmentID, and DepartmentName, dependency between DepartmentID and DepartmentName must be removed into a separate table, leaving only EmployeeID dependent on the DepartmentID. 3NF ensures a structured and efficient database design that minimizes update anomalies. Why Other Options Are Incorrect :

    1. Remove partial dependencies in a relation : This is the goal of Second Normal Form (2NF) .
    2. Eliminate duplicate data and achieve minimal redundancy : While normalization reduces redundancy, this is a broader goal and not specific to 3NF.
    3. Guarantee that every relation contains a candidate key : This is ensured by the very definition of a relation, not by 3NF.
    4. Ensure that no two rows have identical data across all columns : This is achieved by defining primary keys, unrelated to 3NF.

    Practice Next