The importance of database normalization

Normalization is the process of eliminating flaws in poorly designed databases. A poorly designed database is inconsistent and creates problems when information is added, deleted, or updated.

The following are the key steps of database normalization in the database design process:

Resolving database exceptions

The normalized forms are 1NF, 2NF, 3NF, BCF, 4NF and 5NF , eliminating all insert, update, and delete exceptions.

Insertion ExceptionOccurs when you try to insert data from a record that does not exist.

Delete exception means that data is to be deleted, but due to poor database design, other records are also deleted.

Eliminate data redundancy

Storing the same data item multiple times is called data redundancy. Normalized tables do not suffer from data redundancy.

Data dependencies

Data is stored in the correct table and ensures normalization.

Data Isolation

A well-designed database indicates that changes to one table or field will not affect other tables. This is achieved through normalization.

Data consistency

When updating, if a record is missed, it may lead to data inconsistency. Normalization solves this problem and ensures data consistency.

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