Application of Data Granularity in Warehouse for E-commerce Website

Data granularity decides the amount of data in data warehouse and the ability to answer queries.Multiple-granularity can not only satisfy the requirements of the amount of data to a certain extent,but also meet the requirements of the ability to answer queries.So in the design of data warehouse,multiple-granularity becomes the preferred.When the data warehouse using multiple-granularity,we will face with how to manage data-granularity problem.This paper firstly studies granularity level and multiple-granularity,puts forward granularity table in order to manage data granularity,expounds the definition process of granularity table,analyzes the advantages of granularity table;and puts forward the process of data warehouse multi-dimensional model based on granularity table.