Modeling Irregular Dimensions in OLAP

摘要：

Pre-aggregation is one of the most effective techniques in OLAP to ensure quick responses to user queries in data warehouses.The technique usually requires dimension hierarchies to be onto , covering and self-onto.However , in r1eal-world applications , many irregular dimensions do not meet the requirements.To solve the problem , a novel dimension model is proposed to support the modeling of irregular dimensions by defining a partial mapping from a child level to a parent level.Based on the four cases of the partial mappings among different levels , the model can express the special relationships among the levels in irregular dimensions, such as non-covering and non-onto relationships.Furthermore, a cube model is defined based on the dimension model , along with some typical OLAP operations.The mapping from the multidimensional model to relational tables shows that the model provides a feasible way to overcome the difficulties caused by irregular dimensions.

关键词： data warehouse OLAP dimensional model irregular dimension

作者: Liu Hongmin Han Xie

作者单位: College of Electronics and Computer Science and Technology, North University of China, Taiyuan, 030051 China

会议类型: 国际会议

会议名称: 第七届国际测试技术研讨会

会议地点: 北京

会议语种:英文

在线出版日期: 2007-08-05（万方平台首次上网日期，不代表论文的发表时间）