XML Modeling Based On Heterogeneous Data Connection And Its Realization

With the continuous increase of the need for network application and enterprise decision-making support system, more and more applications need to visit various kinds of heterogeneous data sources and data connection and data selection have become a hot topic for current research. XML (eXtensible Markup Language) as a solution to heterogeneous data integration and heterogeneous data exchange has its inborn advantages. XML includes a great deal of self-descriptive markers to accurately express various meanings of information; it provides abundant methods for data conformation and resolution; it can adapt to various and diverse network application environments and thus it is extensively applied in data exchange and interaction between heterogeneous systems, which offers new carriers for information modeling, exchange and calculation.The article expatiates on a method of establishing heterogeneous data sources to connect the information model and the metadata mapping model by using the XML DTD modeling technique. Through this method the heterogeneousness between the subsystem of the information management system for the Degree Office of the Graduate School of HUST and the degree management systems of each college and department of HUST was accomplished; and connection between the heterogeneous data sources of each college and department and the subsystem of the Degree Office of the Graduate School of HUST, and operation of the heterogeneous data were realized, which makes information commonly shared.At the realization of the heterogeneous data connection and the metadata mapping model, the idea of mapping from the Platform Independent Model (PIM) to the Platform Specific Model (PSM) in MDA development was used for reference. Transformation of the SQL clauses from platform independent query to platform specific query was realized. Finally, SAX interfaces for the resolution of XML files including the heterogeneous data source connection information and XML files including the metadata mapping information were compiled, which makes the connection between the subsystem of the Degree Office of the Graduate School and the heterogeneous data sources of each college and department, and the selection of graduate degree information of HUST realized.