Design And Implementation Of Heterogeneous Data Sources Integration System Based On Middleware

With the development of the information technology and the popularization of the network,more and more heterogeneous data sources had been produced;In order to make good use of these information resources,we need to solve the integration problem of the heterogeneous data sources.The purpose of data integration system is to provide users with seamless and flexible access to heterogeneous data sources through a unified query platform which can hide the difference of underlying data sources.On the bases of relevant theories and technologies of heterogeneous data integration,this paper presents a Mediator/Wrapper integration system called HDSIS (Heterogeneous Data Sources Integration System),which is based on the Middleware. This system uses XML technology to solve the problem of heterogeneous grammar. And it uses the advantage of ontology to describe precise semantic relationships,and uses OWL(Ontology Web Language) to represent global ontology and local ontology. Additionally,HDSIS masks the platform discrepancy of data sources based on Web Service technology.A heterogeneous data sources integration prototype system under the HDSIS frame is realized and is applied to an OnlineRetailer system.The client of the prototype provides a unified query interface based on the global ontology,and can perform data query.The server of the prototype carries out functions such as the registration of data sources,the configuration of integration task and system management.The main research subjects of this paper are as follows:(1) Architecture design of the heterogeneous data resources integration system. Each function of the system module is designed in detail and the key modules of the prototype system are realized.(2) Conversion from relational database schema to XML schema with restriction and semantic information.In this paper,XML Schema is used to define the integration schema and each heterogeneous data source should be transformed into a unified XML Schema,so that the system will have higher flexibility and scalability.(3) The integration solution which based on the mapping between global ontology and local ontology is put forward to solve the problems of semantic heterogeneity.(4) The realization of the global query decomposition algorithm according to the data source.(5) The adoption of Web Service and SOAP technology to solve interoperability problems between heterogeneous systems.The method of wrapping data source to construct Web Service features the prototype with the following good qualities,loose coupling,more flexibility and more extensibility.With this method,the seamless data integration can be exactly achieved.This article is about the work of the HDSIS,through which it provides a unified and transparent integrated interface of inquiry for the application in the domain of data sharing,data analysis,decision-support,and so on.