Research On Middleware Technology For Integration Of Heterogeneous Database Based On XML Technology

Along with the deepening of informatization, the need for data sharing and data exchange from existing heterogeneous database is being enhanced constantly. Therefore, an effective method will be needed to deal with data sharing and data exchange in heterogeneous environment, so that an open and collaborative software environment can be formed to complete various work and business decision. The related technology of heterogeneous database integration is studied according to this demand combining with the project of "Credit file system of enterprise and legal Representative for Hei Long Jiang Province".This thesis first discusses the advantages and disadvantages of the related technology of heterogeneous database integration. Afterwards, a thorough research on the schema mapping technique which is the critical technique of heterogeneous data integration is carried on. FLSD is proposed based on the analysis of the merits and shortcomings of the machine learning schema mapping. FLSD increases a feedback system which can learn new knowledge created from working process of the machine learning system, and improve the matching accuracy rate and matching completeness rate. Moreover, FLSD also increases a learning machine which is based on the constraint information, the learning machine makes up for the information which is lost by the learning machines of LSD, and makes a further promotion for the matching accuracy rate.XMLHDIM middle ware system was designed combining with FLSD system, and Lav mode of schema integration is adopted to provide a good scalability for XMLHDIM system. The use of FLSD makes a great enhancement to the automation level and intelligent level of XMLHDIM system, besides, it also decreases the workload for artificial matching work and raises the efficiency of schema matching work.Finally, a set of experiments were carried out to verify the performance of FLSD system in terms of the implementation of "Credit file system of enterprise and legal Representative for Hei Long Jiang Province". The results show that FLSD system can obviously improve the matching accuracy rate and matching completeness rate of schema matching, and further increase the automation level of schema matching work.