Database Normalisation Questions Medium
The fourth normal form (4NF) is a level of database normalization that builds upon the concepts of the previous normal forms (1NF, 2NF, and 3NF). It further eliminates redundancy and dependency issues in a database design. The advantages of using 4NF include:
1. Elimination of multi-valued dependencies: 4NF helps in eliminating multi-valued dependencies, which occur when a table has multiple independent sets of multi-valued attributes. By decomposing such tables into smaller, more focused tables, 4NF reduces redundancy and improves data integrity.
2. Improved data consistency: By eliminating multi-valued dependencies, 4NF ensures that each attribute in a table is functionally dependent on the primary key. This improves data consistency and reduces the chances of data anomalies or inconsistencies.
3. Simplified database maintenance: With 4NF, the database structure becomes more streamlined and focused. This simplifies the process of maintaining and updating the database, as changes only need to be made in the relevant tables rather than across multiple tables.
4. Increased query efficiency: By reducing redundancy and dependency issues, 4NF improves query efficiency. With a well-normalized database, queries can be executed more quickly and accurately, leading to improved performance.
5. Flexibility and scalability: 4NF allows for easier expansion and modification of the database structure. As new requirements arise or the database needs to accommodate additional data, the well-normalized design makes it easier to make changes without impacting the entire database.
Overall, the advantages of using 4NF include improved data integrity, simplified maintenance, increased query efficiency, and flexibility in adapting to changing requirements. It helps in creating a more efficient and reliable database design.