A Level Computer Science OCR Practice Exam

In normalization, why is it important to create new tables in the Third Normal Form (3NF)?

1. To prevent data duplication and create efficiency

2. To ensure all entities have proper relationships

3. To enforce constraints on the primary key

4. To document the state of the database

The correct answer is: To prevent data duplication and create efficiency

Creating new tables in the Third Normal Form (3NF) is essential primarily to prevent data duplication and enhance efficiency. 3NF achieves this goal by ensuring that all non-key attributes are fully functionally dependent on the primary key, eliminating redundancy. In doing so, the database becomes more efficient in terms of storage and retrieval processes, as it avoids unnecessary duplication of data across multiple records. By organizing data into appropriate tables according to 3NF, it also leads to better data integrity and consistency. This structure makes it easier to update, delete, or insert data without the risk of creating inconsistencies that can arise from duplicated information in multiple locations. Hence, focusing on reduction of redundancy and optimizing data access is a core principle of normalization, and particularly in the context of Third Normal Form.