Distributed Database Integration Structure Based On Thematic Object

A large amount of database resource has been accumulated in electric government after many years' construction. But the databases are distributedly built and operate separately without efficient resource sharing. How to integrate them is a realistic problem.Generally, the information demand of decision-making level is theme-oriented and information should be organized centered the theme closely related with decision-making. This paper presents a distributed database integration structure according to the distribution property of the database system in e-government, combining object-oriented feature of Web application environment. This structure models the thematic object using object-oriented method and decomposes the complex object into a series of simple objects through the thematic object's decomposition. The encapsulation property makes the complexity of the object and its implementation transparent to users. A transparent transformation mechanism is achieved based on the mapping principle of data-relation model and official dada from different dada sources distributed in the web are connected at the low level.Data extraction and integration in hetero multi-database system are realized so as to provide the government with a theme-oriented, uniform data search environment by the means of a global database.