What is database normalization and why is it used?

What is database normalization and why is it used?

• A. Organizing data to reduce redundancy by separating into related tables; achieves data integrity and easier maintenance.
• B. Storing all data in a single flat table for simplicity.
• C. Increasing data redundancy to speed queries.
• D. Normalization is about indexing only.

Answer: (A)

The main idea being tested is that database normalization reorganizes data into related tables to reduce redundancy and preserve data integrity. By splitting information into logical pieces and using keys to relate them, the same fact isn’t stored in multiple places. This means updates, deletions, and inserts affect only the relevant data, preventing anomalies and inconsistencies. It also makes maintenance easier because changes in one place don’t require updating many duplicates. Keep in mind that normalization can lead to more tables and more joins when querying, but the payoff is a flexible, scalable design with fewer chances for anomalies. The other options miss the point: a single flat table creates duplication and inconsistencies; increasing redundancy doesn’t improve integrity; normalization isn’t primarily about indexing.

The main idea being tested is that database normalization reorganizes data into related tables to reduce redundancy and preserve data integrity. By splitting information into logical pieces and using keys to relate them, the same fact isn’t stored in multiple places. This means updates, deletions, and inserts affect only the relevant data, preventing anomalies and inconsistencies. It also makes maintenance easier because changes in one place don’t require updating many duplicates. Keep in mind that normalization can lead to more tables and more joins when querying, but the payoff is a flexible, scalable design with fewer chances for anomalies. The other options miss the point: a single flat table creates duplication and inconsistencies; increasing redundancy doesn’t improve integrity; normalization isn’t primarily about indexing.