Entity Relational Model and Dimentional Model

Relational modelling is used for the modelling of transactional data in relational databases while dimensional modelling is normally used for the modelling of dimensional data in data warehouses. In relational modelling the attention is on identification of fundamental or strong entities involved in the execution of business transactions, while in dimensional modelling it is on classification of associative entities that bring business measures.[1] Dimensional modeling is a database design practice developed specifically for designing data warehouses. Its objectives are to create database structures that end users can easily understand and write queries against, and to optimize query performance. It has become the leading approach to designing data warehouses in practice and has proven to be a major breach in developing databases that can be used directly by end users. Dimensional modeling is not based on any theory, but has clearly been very unbeaten in practice.[2]