Optimize the Data Structures in Relational Database by Normal Form

In the database design phase,construct a well-structured relational schema and a compliant database is very important.A well-structured database can avoid anomalies when insert or delete in data manipulation and reduce redundant data in the database.In a relational database,we can raise the grade of nomal form table by standard the table and make the date's structure more reasonable in the datebase.Normal form have 1NF 2NF 3NF BCNF 4NF and 5NF.This article starting from the concept of functional dependency,for the purpose of design a well-structured table,introduce the important applications of normal form in database design by several examples.