The Design And Implementation Of Metadata Model Driven OLAP System

The development of information technology arouse a soar demand of various detail, accurate kinds of data from different industries. As an important tool of information processing in modern enterprises, report is a basic function of information systems. Essentially, report is a kind of abstract generalization and presentation of data, it uses a more powerful and convenient way to describe and present enormous data collection. However, because different enterprises have different businesses, so even they are using the same system, the reports they want are still different. Besides, Chinese reports are famous for their complex style and statistics. Most traditional reporting systems are designed based on foreign simple report models, which can not fit complex reports well.User often requires that data content, style should be stemmed from certain specification or standard in order to interchange, update, index, integration and so on. All of these are related with metadata. Based on this background and requirement, by doing research and studying on related metadata management and model building theories such as CWM, MDA, aiming at the practical problems the author encountered in a project of telecom operator, this paper focus on metadata models in OLAP system, tries to demonstrate the models' effectiveness and rationality and the OLAP system's universality from a new angle.Focusing on the OLAP system's metadata model, report model and their presentation and instantiation,this paper mainly does the following jobs :Firstly, the paper starts from the research and study of common metadata management and modeling theories, such as CWM, MDA etc, which introduce related theories, approaches and specifications. By combining the OLAP systems' characteristics and problems in telecom operators, proposes a new metadata model building methodology based on MDA.Secondly, during the model analyzing period, through the research on data source, report, database and their relationship, the key point is the modeling of OLAP system, which includes data source metadata model, report metadata model and database mapping model, etc. And mainly use star schema and xml documents to represent and instantiate them.The OLAP system's design and implementation are based on the metadata models. This part mainly designs the system's function, architecture and gives datail introduction of two modules. Among which it gives enough emphasize on the models application in the system and report instance's process.Lastly, according to the detailed implement of different kinds of report instance, the verifycation and result analysis parts are completely done, which demonstrates that the metadata models of OLAP system are feasible.To conclude, this paper mainly proposes a metadata model building methodology which gives a feasible solution for supporting whole system. During which it illustrates how to modeling the OLAP system metadata based on CWM by modeling the specific metadata. After that, using detailed implement of models in the system to demonstrate that the metadata models efficiency. The system performs well and can adapt the various kinds of business requirements to meet the system administrators' and business men's need.