Normalization

What is Normalization?

If a database has two or more tables having some same fields it has data redundancy. It causes inconsistency; for example, a customer bought some products from a store, his details are attached to each product wrong, it should have been added only once. We perform normalization to avoid data redundancy. Data redundancy causes data corruption and anomalies in functioning, so it must be avoided when creating a database.

How does Normalization work?

Normalization eliminates redundancy and arranges the storage in the best way. The proper use of foreign keys helps in achieving it. The efficiency of the database is sometimes measured by its normalization.

Types and examples:

There are three main types of normalization: 1NF, 2NF, and 3NF.

First Normal Form (1NF): A database table would be called in first normal form if it has only atomic valued attributes, stored values are in the same domain, all columns have unique headers, and storing order is not sensitive.

Second Normal Form (2NF): A table would be called in the second normal form if it has all characteristics of 1NF and it has no partial dependency.

Third Normal Form (3NF): A table would be called in third normal form if it has second normal form and it does not have transitive dependency.