Research And Application Of Data Warehouse Technology Suitable For The AFC System Of City Rail Transit

Data warehouse is a data set which is subject-oriented, integrated, steady and time-variant, it is suitable for manager to support decisions. Data warehouse technology has been abroad made a wide range of applications, and its application in China just belongs to start. Automatic fare collection (AFC) system of rail transit has been considerably developedt with city's rail transit development in China, and the on line transaction processing system more completed has been builded. Large amounts of data have been accumulated of AFC operation company of rail transit after application in many years, which implied a large number of valuable information. How to use these data to mine informations in depth for servicing the operation decisions is becoming the important things at present of the operation company of rail transit.Through refering to the materials to understand the application status at present of the data warehouse technology and data mining analysis of rail transit industry in China, finding the infrastructure of the information system has been doing well of the industry, AFC system is also widely used, and its database has stored a large number of data. But for a variety of reasons, the status is still in a wait-and-see in the aspects of technology applications of data warehouse and data analysis, and without really carrying out.This paper analyses the status and makes a detailed introduction of the knowledges on data warehouse, such as the definition of the data warehouse, structure, ETL (extract, transform, loading), ETL tools and application process. In terms of the basis of the AFC systems in Beijing and Nanjing rail transit, the author had researched of and analysed some process and relative techniques to building a data warehouse on the business systems.The paper introduces the technique development status at present and basic principles of data warehouse as well as the relative thchniques to construct a data warehouse. In terms of the special circumstances of AFC, the author resolves the basic problems of constructing data warehouse, designs and establishes a data warehouse model that is suitable for the analysis demands of Decision Support System (DSS), proposes and completes in highlight two sets of ETL program aimed at the AFC systems, implements the on-line analysis and data analysis report displays on multi-dimensional data warehouse model, provids basic theorys and solutions on the application of data warehouse for operation company of rail transit.Finally, the system has been tested. The system runs smoothly, and has good performance. It proves that the ETL tools designed can complete ETL requirements of the data warehouse very well, and has features of easy-to-use and good flexibility.