Dimensional Modeling and E-R Modeling In The Data Warehouse

Dimensional Modeling (DM) is a favorite modeling technique in data warehousing. In DM, a model of tables and relations is constituted with the purpose of optimizing decision support query performance in relational databases, relative to a measurement or set of measurements of the outcome(s) of the business process being modeled. In contrast, conventional E-R models are constituted to (a) remove redundancy in the data model, (b) facilitate retrieval of individual records having certain critical identifiers, and (c) therefore, optimize On-line Transaction Processing (OLTP) performance.