Normaliseerimine

Normalization is a process used in database design to organize data in a way that reduces redundancy and improves data integrity. It involves dividing a database into two or more tables and defining relationships between the tables. The goal is to ensure that data dependencies make sense and are properly enforced.

The normalization process typically involves several normal forms, each representing a higher level of organization and data integrity. The first normal form (1NF) requires that each table cell contains only a single value, and each record needs to be unique. The second normal form (2NF) builds on 1NF by ensuring that all non-key attributes are fully functionally dependent on the primary key. The third normal form (3NF) further refines the database by removing any transitive dependencies, where non-key attributes are dependent on other non-key attributes.

Higher normal forms, such as Boyce-Codd Normal Form (BCNF) and fourth normal form (4NF), address more complex dependencies and ensure that the database is in its most optimized state. Normalization helps in maintaining data consistency, reducing the risk of anomalies, and making the database more scalable and easier to manage.

However, normalization can sometimes lead to performance issues due to the increased number of tables and the need for complex joins. In such cases, denormalization, which involves combining tables to reduce the number of joins, can be used to improve query performance. The balance between normalization and denormalization depends on the specific requirements of the database and the trade-offs between data integrity and performance.