Research On Data Synchronization Technology Of The Heterogeneous System For Railway Information Sharing Platform

China Railway informatization has made remarkable achievements after years of construction, information technology infrastructure has begun to take shape, but the phenomenon of construction alone, configuration alone of the equipment, self-contained still existed in railway information system. The exchanges of the data between systems which rely on manual or interface transfer are very common. That did not achieve the sharing of information,"information island" problem has not been eliminated, information sharing and utilization needs to be improved, and it is imperative that should establish the sharing mechanism of the railway information resources. Gradually optimize the interoperability mode of the railway business information system, standardize the information sharing exchange patterns of the systems, establish the information sharing mechanism to get rid of the "information island" of the various business information systems in the railway, and promote sound and rapid construction of railway information developing.Demand for railway sharing information based on the analysis, the paper has analyzed the data exchange mode and rail longitudinal data, as well as cross-sectional data and the data path, the road outside the data for the data exchange program of the railway information sharing platform. The dynamic data of the high real-time via MQ (Message Queue) for transmission, the static data of the non-real-time via ETL (extract, transform, load) for the data exchange, and the exchange method of the amount of information is not big, non real-time data based on the message server, which can use by data and data order. Based on the analysis of the variety of heterogeneous database data synchronization method, SDO (Service Data Objects) and the overall architecture of the rail data exchange platform, the paper has proposed a method of using SOA to build the heterogeneous database data synchronization method in the data exchange platform. This paper has used the Web Service and XML technology to design the heterogeneous database data synchronization platform solutions for the platform of the information-sharing, the overall architecture of the program includes data source layer, logic layer, Web services layer. The data layer is responsible for the data extraction which can use the method based on the log, the paper has obtained the synchronization change data by analyzing the log. Logic layer is responsible for data package, data conversion and data updating process, the paper has achieved the heterogeneous database access, the data encapsulation has changed the format for the SDO data graph, XML format, and the mutual conversion between relational SQL databases. As a data exchange format, XML is used for interaction between applications and data transmission, and has achieved the complete process of sharing from the source database to the central database, and to the updating of the target database. Web service layer encapsulates the logic layer data in the target database, which is used to shield the heterogeneity of the operating system and software platform, and reduce the coupling between systems. Finally, the paper has discussed the security of the solutions, and briefly analyzed the feasibility of the program.