Design of XML-based heterogeneous database access

With the development of computer network and database, traditional database has been increasing unable to meet the needs of data sharing and interoperability. Meanwhile, it is impossible to abandon all the existing database systems; therefore, the research of simultaneously accessing and processing data from a number of databases has become an inevitable trend. The XML-based query extension system applies XML to expand SQL query and provide the database programming staff a universal interface to improve program reusability, lower the cost of software development, so as to more reasonably and effectively solve the heterogeneous multi-database data extraction and sharing.