There are unique criteria in DW that differentiate it with database management system (DBMS). DW is a subject oriented, integrated, time varying and non-volatile collection of data[7]. It contains historical data and those stored data will not be either deleted or changed. Analyzing historical, summarized and consolidated data could lead to precious information such as trend and behavioral correlation. The uniqueness of DWs features cause differences in DW modeling and design. For example in DBMS, redundancy should be eliminated to enhance business process while in DW the existence of redundancy is required to enhance DW performance. However, keeping all historical data that had rarely changed is costly since it requires big data space. To encounter this problem, Kimball et al (2008) proposed slowly changing dimension method to increase its efficiency [9]