Dimension, Fact, and Measure in Data warehouse
Datawarehouse is the storehouse or central repository for structured data. Data coming from various resources CRM, ERP, Billing, Supply chain, etc…., are first cleaned, transform, and then loaded into a storehouse called a data warehouse.
In order to store data in the data warehouse, we use a design pattern called Star Schema. Design patterns consist of facts & dimensions tables that resemble star.
Facts:
1) Facts are the numerical values, observations, and subject of analysis.
Example: temp, sales orders, exchange rates
Dimensions:
1) Dimensions are the textual values, and the context of analysis contains most attributes.
Example: product, people, places & concepts
Measures:
1) Measures are the property on which min, max, avg, count, sum, etc… calculations can be made.
In a star schema, facts and dimensions tables are linked with the help of primary and foreign keys of the tables.