Research On Distributed Database Integration System Based On XML

In many enterprises' information construction process,each department or the subsidiary company of the enterprise organizations has developed different information system to maintain data according to their own need, so enterprise's entire information property was split as"isolated island of information"which we usually said. With the unceasing development of enterprise information construction and the Web, information exchanges among enterprises are becoming closer and closer, and XML has become the standard format for data exchange in the Web. In the other word, with the development of Web, XML has become the standard format for data exchange in Web. In fact,many industry groups have defined DTD or XML Schema to specify the format of the XML data to be exchanged between their applications. So how to integrate and publish these data from distributed database as XML document accord to users'need is a exigent questions.In order to realize data integration based on XML, data transformation between XML and database must be taken into consideration. The most important task is to establish mapping between XML and relational database. In this paper, a describing regulation, R2X(Relational To XML), was defined to express mappings of distributed database data into XML. We can define mapping file to describe this mapping from relational data to XML that conforms to user's need. At last, aiming at distributed database, a model of integrating distributed database based on R2X was proposed to achieve transparent access and unified query. This model provides a global view to users and the users query this view by XQuery. In this paper,the key questions are researched which includes the mapping from relational data to XML, query processing, splitting method of distributed database data and the corresponding method to integrate these data fragments etc.