Research On Heterogeneous Data Integration Based On OGSA-DAI

Distributed heterogeneous data integration is the key issue which the information construction is facing. These information systems are gradually built up with the information needs of units,and they are built on different operating platforms,used different storage structures and information representation, serviced for their applications, and information is so independent and closed that it is difficult to interact with each other. However, the data integration is to achieve the effective integration and transparent access for distributed and heterogeneous data resource, which provides users with a unified interface without affecting the existing system.According to the characteristics of heterogeneous data sources and the limitations on existing integration middleware, on the basis of analyzing the advantages and disadvantages of heterogeneous data integration, some important key technology and integration methods, combining grid and OGSA-DAI(Open Grid ServicesArchitecture—Data Access and Integration), the heterogeneous database access and integration system based on OGSA-DAI(integration system) was designed and built. In this system, the distributed query module was added to overcome the deficiencies which existed in a multi-database query in the OGSA-DAI; the virtual database was introducted to implement the conversion between modes, which provided a unified search platform for distributed query module; he service agent was used to cover semantic heterogeneity between the different databases; and Integrated role, the interaction between services and the access process in underlying database were detailed research and analyzed based at last. Finally, the digital campus as a test environment was used to verify rationality and applicability of the integration system, and the integration process of system and the test results are anaylzed and illustrated in detail. It is clear that this system can mask the differences among heterogeneous databases, form into a single standardized data source and access transparently to different databases in cross-platform system.