Application Of SQLXML In B/S Three-layer Structure

With the popularity of the Internet and WWW, the host/terminal or C/S can not meet the current requirements which conclude the open interconnection of global network, information sharing , and that information can be available everywhere, so there have been B/S model, that is, Browser/server model.The biggest advantage of B/S structure is that we can operate anywhere without having to install any special software, and the system is easy to expand. However, this structure means the need to connect the server frequently to respond to user requirements of search query or data access through the browser. Access database server too much will lead to overload even collapse of the server.For this reason, on the basis of research of B/S three-layer system, this thesis raises a combination of XML and SQL data processing method taking a kind of data processing problem encountered in the practical application of laboratory information management system for example and designs a B/S system with a three-layer structure, which adopts the technology to reduce the access to database and the burden on the server side and to improve the system efficiency. Xml document was used to store data which from the presentation layer of B/S system. Finally,the data in the XML document was saved in the relational database. Therefore, begining with the relational storage of XML documents, the mapping arithmetic based on XML Schema was studied and the improved arithmetic was presented.