Glossary · Database

Normalization

The process of organizing database tables to reduce data redundancy and improve data integrity.

Database normalization is the process of structuring a relational database to reduce data redundancy and improve data integrity. Normalization involves dividing large tables into smaller, related tables and defining relationships between them through foreign keys. The process follows normal forms: First Normal Form (1NF–eliminate repeating groups), Second Normal Form (2NF–remove partial dependencies), Third Normal Form (3NF–remove transitive dependencies), Boyce-Codd Normal Form (BCNF), and higher forms. While normalization improves data integrity and reduces storage, it can increase query complexity through more joins. Denormalization (strategically introducing redundancy) is sometimes used in analytics and read-heavy workloads to improve query performance.

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