Dimensional modeling: Outriggers

An outrigger is a dimension table or entity that is joined to other dimension tables in a star schema. Outriggers are used when a dimension table is snowflaked.

Outriggers are tables or entities that are shared by more than one dimension.

A table or entity that is included in a hierarchy but is not directly related to the fact table are known as outriggers. Outriggers are often used when a dimension table or entity is referenced by another dimension. The primary key of an outrigger is referenced by the foreign key of a dimension table or entity.