It is a systematic approach of decomposing tables to remove data redundancy and undesirable characteristics like Insertion, Update and Deletion. Normalization is a multi-step process that put data into the tabular form and removing duplicated data from the tables.

Advantages
  • It helps to the reduction of redundant data.
  • It has a much more flexible database design.
  • It is better to handle on database security.
  • It is dealing with data consistency within the database.
Rule of Normalization
  • 1NF(First Normal Form)
  • 2NF(Second Normal Form)
  • 3NF(Third Normal Form)
  • BCNF(Boyce and Codd Normal Form)
  • 4NF(Fourth Normal Form)
BY Best Interview Question ON 27 Jan 2019