What is normalization?

Normalization :

Normalization is a process of effectively organizing the column and table of a database to reduce data redundancy and improve data integrity.

Normal form of a table

1NF

First Normal Form (1NF)

All attributes in a relation must have atomic domains.

In this scheme there should be no repeated element in single block.

For example:

2NF

Second Normal Form (2NF)

for implementing this scheme it must satisfied 1st scheme.

Before moving further one should know about the prime attribute and non-prime attribute.

Prime attribute: the entire element which is a part of the prime key.

Non-prime attribute: the entire element which is not part of the prime key.

For this scheme, non prime attribute should be functionally dependent on prime key.

1NF table

Modified to 2NF

3NF

It must satisfy 2NF criteria and there should no relationship between primary key and non primary element data.

For example we have table like this

We can divide above table in two

Boyce-Codd Normal Form

It is developed by the Raymond F Boyce.

X → Y is a trivial functional dependency (Y ⊆ X)

X is a super key for schema R

Normal table

Converting to Boyce-Codd Normal Form

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