"A dimension for which multiple foreign key columns exist in a single fact table to represent different contexts for the same dimension. For example, time is a common role-playing dimension with each date in the fact table associated with a different event, such as order date, ship date, and delivery date." (Reed Jacobsen & Stacia Misner, "Microsoft SQL Server 2005 Analysis Services Step by Step", 2006)
"Instances of a dimension that legitimately has more than one value for a given business transaction, such as order date and shipped date. Each attribute with the dimension is uniquely identified to enable easy differentiation between the different roles, such as Order Date, Order Quarter and Shipped Date, and Shipped Quarter." (Laura Reeves, "A Manager's Guide to Data Warehousing", 2009)
"A single database dimension joined to the fact table on a different foreign keys to produce multiple cube dimensions." (Microsoft, "SQL Server 2012 Glossary", 2012)
"The situation where a single physical dimension table appears several times in a single fact table. Each of the dimension roles is represented as a separate logical table with unique column names through views." (Ralph Kimball & Margy Ross, "The Data Warehouse Toolkit" 2nd Ed., 2002)
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