"A dimensional model is a form of data modeling that packages data according to specific business queries and processes. The goals are business user understandability and multidimensional query performance." (Claudia Imhoff et al, "Mastering Data Warehouse Design", 2003)
"A data model influenced by performance considerations and optimized for data access and retrieval. This is a form of entity-relationship (ER) modeling that’s limited to working with “measurement” types of subjects and has a prescribed set of allowable structures." (Sharon Allen & Evan Terry, "Beginning Relational Data Modeling" 2nd Ed., 2005)
"A dimensional model contains a central fact table and a set of surrounding dimension tables, each corresponding to one of the components or dimensions of the fact table." (James Yao et al, "Development and Design Methodologies in DWM", 2008)
"A data model organized for the purpose of user understandability and high performance. In a relational database, a dimensional model is a star join schema characterized by a central fact table with a multi-part key. The components of this key are joined to a set of dimension tables, each defined by its own primary keys. In a multi-dimensional database, a dimensional model is the database cube." (Laura Reeves, "A Manager's Guide to Data Warehousing", 2009)
"A data model that represents data in a star-like structure of only one-to-many relationships, where each entity has either all relationships having the ‘one’ side or the ‘many’ side." (DAMA International, "The DAMA Dictionary of Data Management", 2011)
"A specialized type of physical data model particular to a retrieval-only database design, commonly used in Data Warehouses and data marts, where de-normalized fact tables are linked to dimension tables. Star schemas and snowflake schemas are examples of dimensional models." (DAMA International, "The DAMA Dictionary of Data Management", 2011)
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