Star Schema Modelling
A Dimensional modelling technique in which a detail fact table is linked to dimension tables.
The information contained in the data warehouse/data mart must be easy for the end-user to use and access. Denormalized designs are easier for end-users to use than highly normalized designs, however these designs are more difficult to design and maintain.
The Star Schema diagram graphically models the end-user's view (i.e., the denormalized view) of how the information is accessed.
Components of a Star Schema Diagram
The diagram has three main components:
· Fact Table and its contents: metric attributes and the foreign keys necessary to join to the dimension tables,
· Dimension Tables and their contents: reference attributes, hierarchical attributes, and metric attributes. The dimension tables are highly denormalized,
· The lines that link the Dimension Tables to the Fact Table.
Star Schema Model
This diagram is a model of a star schema diagram.
Star Schema Example
The following is an example of a star schema for sales items.
