Foreign key in FACT table has reference to the primary key in dimension table.
Business model has two or more logical tables and each table has two or more logical columns. Logical table is on top of Physical table. It can combine the contents of two or more physical tables or from other logical tables.
Facts are analyzed by dimensions.
In hierarchical dimension, one attributes rolls up to ANOTHER, FORMING ONE TO MANY RELATIONSHIP.
Star and Snowflake:
Stars have one to many relationships between the logical dimension tables and logical Fact tables.
Snow flake has relationships between dimensions too
Create bridge table, to create many to many relationships between dimension tables and fact tables.
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