Research And Implementation Of Schema Integration In SIIGRID About Heterogeneous Database

With the advent of information network era, the national government has put forward more rapid and efficient demands. Developing e-government will surly becomes the trend. However, there are many problems in current e-government systems, one of which is the problem of heterogeneous information sources. Information integration technology researches integration problems among heterogeneous data and it will integrate the isolate data to provide a unified view for the users, so that the users can get what they need from gigantic data resources.Due to distribution, heterogeneity and autonomy of the data sources in the domain of social insurance, the existing technologies is difficult to meet current and future requirements of global management and single-point access of the system. The project is encapsulated and published as web services, and implements the transparent access to the grid data sources. It is necessary to produce a kind of method to effectively implement the integration of information sources in current system.The first problem to be solved is the schema confliction among data sources. The paper use the concept of ontology, implement formal union of meta data in heterogeneous data sources. It also creates the methods of schema mapping and the algorithms of query decomposition to solve the problem of semantic confliction in the system.The paper researches the methods of schema integration based on the grid architecture of SIIGrid and uses atomic operations to implement the mappings between global schema and local schema. It presents the algorithms of query decomposition and implements the schema integration in grid environment. The prototype suggests the method effectively solves the heterogeneous problem in SIIGrid.