The Research On XML Document Query Technology And The Application In Digital Library

XML(eXtensible Markup Language)has already been the standard of data storage,exchange and representation on the Internet.With the spread of XML application,more and more data is stored and exchanged in the form of XML.As a result,the demand for query data contained in the XML documents is becoming more and more critical.To fully apply the characters of XML to query,we present our contributions to the improvement techniques of XML query.MarcXchange document is a kind of XML document type for application in the digital library,which can be used as a common data exchange standard to share in the web environment.In order to promote the digital library construction,the paper studies in detail index and query technology of MarcXchange.1.This paper proposes an improved XML index based on LI-MOON code,when we encode indexed documents by B+ tree structure,It greatly reduces the size of indexed documents so that effectively improve query speed.2.For Stack-Tree-Desc algorithm improving the connection efficiency without index and browsing a number of unnecessary nodes to waste resources and affect the query speed.A new connection algorithm is proposed for improving query speed that it searches position by B+ tree index to skip unnecessary element in the list of ancestors and descendants3.Marc_index based on MarcXchange documents is proposed that is using LI-MOON code in accordance with the characteristics of the MarcXchange documents,achieves effectively detection of two nodes ancestor/descendant relations and parent/child relations in the document tree.The other innovation of the index is that it integrate effectively advantages both B+ tree and inverted index to overcome the shortcomings in order to improve query efficiency.Finally,the paper also proposed a query processing algorithms based on Marc_index.