Difference between Star Schema and Fact Constellation Schema

Star Schema:
Star schema is a multidimensional model type that uses simple queries in order to access data from the database. A star schema depicts each dimension with only one-dimension table. Star schema is easy to operate as compared to fact constellation schema as it has less number of joins between the tables. It uses less space as compared to fact constellation schema.

Fact constellation Schema:
This schema is a type of multidimensional model. In this, dimension tables are shared by many fact tables. The fact constellation schema consists of more than one star schema at a time. Unlike the star schema, it is not easy to operate, as it has more joins between the tables. Unlike the Star schema, fact constellation schema uses heavily complex queries to access data from the database.

Let’s see that the difference between the Star Schema and fact constellation schema:

S.NO	Star Schema	Fact constellation schema
1.	A star schema depicts each dimension with only one-dimension table.	While in this, dimension tables are shared by many fact tables.
2.	In star schema, tables can be maintained easily in comparison of fact constellation schema.	While in fact constellation schema, tables cannot be maintained easily comparatively.
3.	Star schema does not use normalization.	Whereas it is a normalized form of star and snowflake schema.
4.	In star schema, simple queries are used to access data from the database.	While in this, heavily complex queries are used to access data from the database.
5.	Star schema is easy to operate as compared to fact constellation schema as it has less number of joins between the tables.	While fact constellation schema is not easy to operate as compared to star schema as it has many joins between the tables.
6.	Star schema uses less space as compared to fact constellation schema.	While fact constellation schema uses more space comparatively.
7.	It is very simple to understand due to its simplicity.	While it is very difficult to understand due to its complexity.