Corba-based Distributed Heterogeneous Database Information Retrieval Model - Applied Research In The University Digital Library

With the flourishing development of E-learning at our country, the lack of E-learning information resources has begun to appear. So it's a key to present E-learning development to accelerate E-learning information resources building. As one of the important education information resources, the networking and area of University's digital library is becoming a vital field of modern education studying and computer application studying. According to current situation of the University's digital library of our country, because of relatively independent development for a long time, causes each University's digital library under the heterogeneous system platform and software construct, that become a great obstacle of realizing the networking and area. Based on such situation, this research proposes a distributed heterogeneous database information searching system model based on CORBA middleware. This model absolutely use existing network and utilize digital book database systems which have been built or under being built. It offers user a uniform search entrance to access the heterogeneous database at different area transparent on the ORB provided by VisiBroker. Consequently, realize the uniform searching between distributed heterogeneous databases. This paper makes a brief introduction about digital library technology, distributed database technology and middleware, etc. Moreover, proposes the four layers model based on CORBA middleware and the actual solution built with VisiBroker. And makes a detail analysis and realization to three key part in scheme, those are IDL mapping,server object at server end and the procedure of calling services at client end.