About Fact Table
* Table in the relational data warehouse that stores the detailed values for measures
* A measure is a summarizable numerical value that is used to monitor your business, e.g. units sold, dollars sold, hours worked, hourly billing rate
* Each column should be either a foreign key to a dimension table or a measure
* Measures should be at the lowest level of detail to provide the maximum flexibility for reporting and analysis
* Many-to-one relationship between fact table and dimension table
* Biggest table in the data warehouse in terms of number of rows