XML在分散式多层次应用系统的效能提升探讨

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Applying XML to Promote Efficiency of Distributed N-tier Application System

Chiu-Liang Chen

Department of Information Management, National Taipei College of Business

ccliang@mail.ntcb.edu.tw

Abstract

Efficiency performance is a key issue in the Distributed n-tier application system. The conventional way of solving efficiency problem is monitoring the chief hardware and thereby spotting and removing the bottleneck. However, in such practice, another bottleneck tends to appear following the removing of one bottleneck.

If we provide information for the web client by XML documents in the web server, the web server won’t need to repeat querying the same data from the database server. Thus, the efficiency will be significantly promoted. When applying XML documents in the web server so as to provide information for the web client, one will unavoidably face two problems: (1)How can one update the XML documents in the web server immediately after the data in the database server vary so as to guarantee the function of real-time information query? (2)How can one make the web server successfully read the XML elements according to the query conditions prescribed?

In order to solve the above two problems, this study proposes an approach of “Dynamic real-time query for XML documents”. Empirically this approach functions well in efficiency real-time information and dynamic query. This approach has been Empirically operated for the curriculum schedule search in the academic system at National Taipei College of Business. The result of efficiency analysis indicates that providing information for the web client by XML documents can significantly shorten the response time and lessen the load for web server as well as database server and thus effectively promote the whole system efficiency.

Keywords?Qdistributed n-tier application system?Bsystem efficiency?BXML?BXML DOM?BXPATH

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