l Database normalization is the process of removing redundant data from your tables in to improve storage efficiency, data integrity, and scalability.
l In the relational model, methods exist for quantifying how efficient a database is. These classifications are called normal forms (or NF), and there are algorithms for converting a given database between them.
l Normalization generally involves splitting existing tables into multiple ones, which must be re-joined or linked each time a query is issued.
Levels of Normalization
• Levels of normalization based on the amount of redundancy in the database.
• Various levels of normalization are:
– First Normal Form (1NF)
– Second Normal Form (2NF)
– Third Normal Form (3NF)
– Boyce-Codd Normal Form (BCNF)
– Fourth Normal Form (4NF)
– Fifth Normal Form (5NF)
– Domain Key Normal Form (DKNF)
Most databases should be 3NF or BCNF in order to avoid the database anomalies.