Research On Storage And Quere Of XML

With the development of research and application on XML, the need that storing and querying XML effectively has been more and more exigent. In order to solve the problem how to store and query XML ,the paper analyzes the research content about storage and query XML in home and abroad, then proposes two XML data clustering storage methods, an XML path expression query approach and two path expression query optimization methods.First, the paper defines an XML model and an XML schema model.These will be the base of the latter research.Secondly, it gives a system architecture of an XML data management system(XMLBase), which provides XML data storage. Users can load documents and do path expression queries via application programming interfaces. It proposes two XML data clustering storage methods,they are Filiation Clustering and Sibling Clustering method.They are fit for XML data Depth First Fetch Algorithm and XML data Breadth First Fetch Algorithm.Then, it defines XML Extent and other conceptions, and proposes an XML path expression query algorithm named XML EMJ, gives the processing including path query decomposition and transformation , path query optimization. Four indices are discussed. From the experiment, the approach improves the efficiency of XML path expression query.And the Query Performance of the approach is better than before .Lastly, the paper proposes two XML path expression query optimization methods, Path Cut and Path Replaced. For query optimization ,they lower the complication of path query by the information of schema. And they improve the efficiency of XML data query , too.The solutions the paper puts forward will be valuable in theory and meaningful in practice for research of XML data management and development of Web, to a certainty.