Western Governors University (WGU) ITEC2104 C175 Data Management - Foundations Practice Exam

When a database is in Third Normal Form (3NF), one crucial rule is that all attributes must be functionally dependent on the primary key. This means that for each non-key attribute in the database, its value must be determined by the primary key, ensuring that there are no transitive dependencies present. In other words, if a non-key attribute relies on another non-key attribute, rather than directly depending on the primary key, it violates the principles of 3NF.

Maintaining functional dependency ensures the integrity of the data and minimizes redundancy within the database. It directly contributes to improving data consistency, as each piece of information is stored in one place only, which helps eliminate anomalies during operations like insertions, deletions, or updates.

The other options present concepts that may relate to database structure but do not specifically pertain to the definition or requirements of Third Normal Form. For instance, while uniqueness of primary keys is important for identifying records, it is not a specific criterion for achieving 3NF. Similarly, while having non-null attributes can be a design consideration, it isn’t a requirement of 3NF. Lastly, relationships between tables are vital to relational database design, and 3NF does not prohibit these relationships but rather focuses on struct