Research And Implementation Of Multidatabase System In Railway Field

At present, enterprises’departments and public institutions produce large amounts of data and choose different ways to manage these data based on different data features and application requirements. This causes information isolation among various departments. It is very difficult to share data among departments. To solve this problem, we need to research data integration technology. However, the information integration is mostly implemented at the upper level of an application The data integration and data sharing on entire enterprise architecture have not been solved. Multidatabase system technology has become an effective approach to solve the information integration and data sharing among heterogeneous data sources. Multi database system technologies aim at multiple heterogeneous, distributive and existed local database systems and provide users with a unified multi-database environment, including unified data type definition, query language, data access methods and so on without lot of changes to the local database.The thesis is to solve the problem of the professional data integration and access in the railway field, so as to support a variety of professional applications. Achieving the above functions the thesis needs to solve two problems:(1) professional data is stored in heterogeneous data sources, including different types of commercial databases or file system. How to utilize the multi-database technology to integrate heterogeneous data sources is a challenge.(2) For the integrated homogeneous multidatabase systems, how to maintain the consistency between the sources and target is another issue.In the paper, the issues above were deeply studied. One homogeneous Multidatabase system was implemented. The main research work includes:Firstly, the integration strategies of heterogeneous database were studied, homogeneous multi-database architecture was designed, and one homogeneous multi-database system was implemented. Secondly, for different data sources, different integration strategies were taken. An access interface of homogeneous multi-database was designed for a variety of applications. Thirdly, according to characteristics of heterogeneous data, updating schemes among structured data, between the unstructured and structured data were designed respectively for maintaining the data consistency.finally, the technical solutions implemented in this paper were verified by experiments. The analysis results showed that approaches developed in the thesis are feasible and effective.