XML Schema Based Compressing Technology Over XML Data Stream

With the modern information society is gradually moving towards the Internet, resulting in a large number of various forms of information driven by rapid development. These isolated, independent, heterogeneous information generated in a long period have been unable to meet the Internet era of spatial information sharing and data exchange needs. XML (eXtensible markup language) emerging in recent years has become the Internet and e-commerce data exchange and that the de facto standard, the XML data stream technology also has emerged.The compression of XML data stream is one of the hot researches. Data stream is different from the traditional, static, stable and lasting relationship between the data, it is dynamic, fast continuous. So the traditional compression method of the XML document, data can not meet the requirements of the data stream environment. The traditional compression method need two-scan data and even multiple-scan to analyze the structure of the data before the compression, and in this way for the network in terms of the data stream will cause a great delay.Therefore, how to effectively complete the compression of XML data stream to save storage space and reduce transmission costs, at the same time if we can support compression of XML data streams directly query processing in order to avoid decompression operations on system resources consumption, as an urgent need to address the problems and research directions.In this paper, starting from study and analysis the environment of XML data streams and the structure of XML data itself, see XML Schema which can be used to improve compression efficiency and compression ratio as the entrance. XML Schema is"XML standard markup language"recommended by W3C in 2001. XML Schema as an XML binding has been more and more widely. XML data stream in the XML Schema met, including all the XML data stream in the definition of element types. Therefore, before the data stream processing, you can analyze XML Schema, access to XML data stream structure of the sequence of events occur and to identify elements of the coding sequence of events to complete the compressed XML data stream. Although not as good as this first element was again scanning the frequency of accurate sequence of events, but this method does not need to scan the data stream can be relatively accurate sequence of events of the elements of the frequency of compression it can only scan for network environment of the XML data stream .Finally, the compression of this paper tested the performance of experiments and analysis of results from the experiment, the compression algorithm in the compression efficiency and compression ratio is superior to the traditional algorithm.