Normalization

Normalization is a process of organizing data to minimize data redundancy.  There are many normalization Forms but among them the up to the 3rd form is most commonly used.

1NF: Eliminate Repeating Groups
For each set of related attributes you have to make a separate table and give each table a Primary Key.

2NF: Eliminate Redundant Data
If an attribute depends on  only part of a multi-valued key then remove it to a separate table.

3NF: Elimate Columns Not Dependant On Key
If attributes do not contribute to a description of the key, remove them to a separate table. All attributes must be directly dependent on the Primary Key.


SnowFlake Schema is an extension of the Star Schema. Any dimension with extended dimensions is called a snowflake schema.