A Study For Distributed Xml Streaming Query Of Nest

The eXtensible Markup Language(XML)is a semi-structured data description language proposed by the W3 C,which is available on the Internet because of its high readability,scalability,self-descriptiveness,and cross-platform features.Extensive application.With the development of Internet technology,Internet users continue to increase,the popularity of network applications,Internet data size is constantly expanding.XML as the current Internet data storage format,data sharing and data exchange of the dominant standards,in many applications are used extensively.In recent years,the rapid development of large data and cloud computing,XML is no longer limited to a single document,the more the situation is the form of data sreaming,cannot be completely stored in a document.Many of the existing applications,XML documents cannot be a one-time into the memory.Traditional XML processing methods rely on XML into the computer's memory,the XML into a tree structure,the query for XML.Obviously,such this query methods are no longer part applicable to the current XML query.The use of XML stream data,the massive data in the form of stream,unilateral scanning query processing approach by researchers generally concerned that XML stream data query has become a hot spot in the field of data.XML stream data due to real-time data arrives,the need for real-time processing,data entry is uncontrollable,and is continuous,no end,once the data processing is completed,unless specifically saved,re-processing need to spend expensive cost of these features,Massive XML stream data to find useful data becomes a challenging issue.Processes that process XML stream data typically parse XML using XML parsers such as SAX,and query XML using XML query languages such as XPath,Xquery,and so on.In order to keep less memory,the XML element after processing is discarded.At present,although there are many XML stream data query methods,but these methods in the description of the ability to slightly less,some do not support predicate filtering,some of the queries efficiency are not high and so on.Therefore,it is very important to study a high-performance,feature-rich query method for XML stream data.The traditional query method can not be applied to the flow data,the existing flow data query method has some shortcomings,according these questions,this paper presents a graph-based XML query automata(GRAT)that uses a graph structure to represent the relationships between subquery tasks for different XML stream elements.The XPath query is implemented by the reduction of the graph.This method provides the main functions of the XPath query and is in a position to perform well in the process of XML stream data traversal.GRAT also applies queries to multiple XML streams nested in a distributed environment.Experiments show that GRAT-based query algorithm can efficiently perform complex XML query,which is efficient,scalable and real-time,and can take care of the requirement of multi-source XML stream data processing,and the throughput of stream data processing reaches a high level.