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Normalization is a process in database design to minimize data redundancy and dependency. The database is divided into two or more tables and relationships are defined between them.

Let's see different types of Normal Forms.

• First Normal Form: Every record is unique in a table and is identified by a primary or a composite key
• Second Normal Form: The table must be in First Normal Form and it should have a single column as its primary key
• Third Normal Form: The table must be in Second Normal Form and must have no transitive functional dependencies. I.e a non-key column must not be dependent on another non-key column within the same table

What is de-normalization and when do you go for it?

De-normalization is a technique sometimes used to improve performance so the table design allows redundant data to avoid complex joins. If the application involves heavy read operations then de-normalization is used at an expense of the write operations performance.