Role Playing Dimension in data warehouse

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Dimensions are often recycled for multiple purposes within the same database. For instance, a “Date” dimension can be used for “Date of Sale”, as well as “Date of Delivery”, or “Date of Hire”. This is often referred to as a “role-playing dimension”.

A single physical dimension can be referenced multiple times in a fact table, with each reference linking to a logically distinct role for the dimension.It is essential that each foreign key refers to a separate view of the date dimension so that the references are independent. These separate dimension views (with unique attribute column names) are called roles.

Typically dimensions in a data warehouse are organized internally into one or more hierarchies. "Date" is a common dimension, with several possible hierarchies:

"Days (are grouped into) Months (which are grouped into) Years",
"Days (are grouped into) Weeks (which are grouped into) Years"
"Days (are grouped into) Months (which are grouped into) Quarters (which are grouped into) Years"
etc.

For more details. Please check Role Playing Dimension in data warehouse

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