Five normalization forms exist, represented by the symbol 1NF for first normal form, 2NF for second normal form, and so on. If you follow the rules for the first rule of normalization, your database can be described as “in first normal form.”
Each rule of normalization depends on the previous rule for successful implementation, so to be in second normal form (2NF), your database must also follow the rules for first normal form.
A typical relational database used in a business environment falls somewhere between second and third normal forms. It is rare to progress past the third normal form because fourth and fifth normal forms are more academic than practical in real-world environments.
Following is a brief description of ...