Types of tables in DWH: Facts and Dimensions
Tables in DWH
- Dimensions are attributes about facts.
- They store textual description about business.
- Dimensions are denormalized due to one to many relationship
Ex: Store, Product, Employee, Customers
Facts are the actual transactions or values being analyzed
- They contain composite primary key where each attribute of primary key is foreign key to the dimension tables
- A fact table contains the facts at the lowest level granularity
Prod Id, Cust Id, Sales Date are Dimension Keys.
Quantity Sold, Amount Sold are Fact Measures/KPI’s
KPI stands for Key Performance Indicators