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In recent years, the data monitoring system based on financial services, network monitoring, security, telecommunications data management, stock information, sensor networks, etc , it’ s object data is a large, continuous, real-time, stream flow data and requested data treatment is real-time, and can also handle a large number of inquiries. Extensible Markup Language (XML) has a good self-descriptive and cross-platform advantages, has become a standard data exchange is widely present in the Web and in enterprises.This paper mainly studies the stock information system , which is based on the XML data stream processing technology, the principal tasks include: 1) design of a Web-based real-time monitoring system on stock information and implement the system prototype; 2) will be released real-time stock information is expressed as XML data flow, the user of the data to monitor stock information are expressed as XPath queries in the abstract. The system will convert the user’ s submitted statements, into the corresponding Xpath statement, according to stock data’ s XML document type definition (DTD) ; 3) In order to be able to use the limited memory, to real-time process stock information, XPath queries are modeled as automata , by parsing the label of the XML data stream to drive the event-driven state machine’ s state transition: when the current status meet the migration conditions which is of receipt of a move to the next state , that is, to move to the next state. When the state is to accept state, query results is returned to the user; 4) In order to effectively support multi-user query, multiple XPath query has been merged and expressed as a non-deterministic finite automata (NFA) in the abstract. Through the use of the path and the state share, to improve the query efficiency; 5) Finally, by design, analysis and research, and experimental data obtained shows that the systems and methods in this paper is effective.
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