DataBase System Introduction Normalization(规范化) is another approach to logical design of a relational database. g E-R approach and normalization approach reinforce each other g Normalization starts with a real-world situation to be modeled and lists the data items that are candidates to become column names in relational tables, together with a list of rules about the relatedness of these data items g The aim is to represent all these data items as attributes of tables that obey restrictive conditions associated with what we call normal forms(范式 E INF-->2NF-->3NF-->BCNF-->4NF--> 5NF Haichang Gao, Software School, Xidian UniversityDataBase System Haichang Gao , Software School , Xidian University 4  Normalization (规范化) is another approach to logical design of a relational database.  E-R approach and normalization approach reinforce each other.  Normalization starts with a real-world situation to be modeled and lists the data items that are candidates to become column names in relational tables, together with a list of rules about the relatedness of these data items.  The aim is to represent all these data items as attributes of tables that obey restrictive conditions associated with what we call normal forms (范式).  1NF --> 2NF --> 3NF --> BCNF --> 4NF --> 5NF Introduction