What is the purpose of database normalization?

Database normalization is the process of organizing data in a database to:

• Reduce data redundancy: Avoid duplication of information in different places, saving space and preventing inconsistencies.
• Increase data integrity: Ensure accuracy and reliability of data by eliminating insertion, update, and deletion anomalies.
• Simplify the database structure: Create a more logical and consistent organization of data.

The main normal forms (NF):

• 1NF (First Normal Form): Each cell of the table contains an atomic value, and there are no repeating groups of columns.
• 2NF (Second Normal Form): It is in 1NF and all non-key attributes depend fully on the primary key.
• 3NF (Third Normal Form): It is in 2NF and all non-key attributes do not depend transitively on the primary key (i.e., they do not depend on other non-key attributes).

Higher normal forms (e.g., Boyce-Codd Normal Form) are often used, but 3NF is sufficient for most practical purposes.