A Study On Transparent Access Of Heterogeneous Database

Many universities have put "Digital Campus" on their agenda. One of the major problems is to integrate all kinds of data and resources and make them accessible through campus portal. To this end, a universal data interchange platform should be built to eliminate "isolated islands of information" caused by the campus network. Data exchange could achieve data-sharing heterogeneous databases and redundantly storing the method for data exchange based on XML by eliminating conflict between data in each database. At present,is in common use. However, it is inflexible because it relies on customizing a XML schema in advance. This paper designs a dual-XML-schema solution of database exchanging to solve the problem.The source and target convert each relation schema to XML schema respectively with XML Schema Language. The heterogeneity between source and target would be eliminated by XML schema mapping with mapping rules.Since the mapping rules is created dynamically, this can adapt itself to the change occurred in source or target by updating mapping rules. dual-XML-schema solution of database exchange is applied to meet the data sharing requirement of basal universities information database. This paper also gave detailed design and implementation of the pivotal process in data exchange system, including schema conversion, schema registering, schema mapping,data exchange and so on. Finally this paper used a representative example to validate the feasibility of dual-XML-schema solution. Due to all the modules are relatively isolated and easy to extend, the solution could be used in kinds of science domain to solve data-sharing between heterogeneous databases.