Dimensional Model

A Dimensional Model is a database structure that is optimized for online queries and Data Warehousing tools.  It is comprised of "fact" and "dimension" tables.

A "fact" is a numeric value that a business wishes to count or sum.

A "dimension" is essentially an entry point for getting at the facts.  Dimensions are things of interest to the business.

Dimensional Model

Dimensional Models are designed for reading, summarizing and analyzing numeric information, whereas Relational Models are optimized for adding and maintaining data using real-time operational systems.