Research On XML Storage And Query Technology Based On Relational Database

After proposed by the W3C in 1998, XML has become a new standard for data representation and data exchange on the internet. All trades and professions are using XML to describe the domain information.Along with XML documents sharp growth, how to effectively storage, manage and inquire these XML data become a research hot spot in XML domain and a new research direction in database domain.This paper focuses on XML storage and query technology based on relational database.In this paper,we first discuss XML storage technology based on relational database.After several typical XML-RDB mapping methods are introduced, in-depth analysis are carried on several improved storage methods.These typical XML-RDB mapping methods include mapping method of edge model,mapping method of node model,structure mapping method and constraint mapping method. Among the improved storage methods we focus on X-RESTORE method,mapping schema from XML to relation based on E-Schema and the XML storage model based on extended Huffman Coding.Then from above research and theory of Threading-Numerous-Tree based on Threading-Binary-Tree we put forward a XML storage model based on Threading-Numerous-Tree.The new storage model can effectively solve the problem that it is difficulty to realize codeing if XML tree's depth increases in XML storage model based on extended Huffman Coding.After introduction of XML storage technology,then this paper focus on the key technologies in XML index and query.At first,XML index technologies including Structure-Outline index, Node-codding index and overall index are researched which are classed according to mechanism of response query and processing query.After that,we research on XML query technologies including XPath query processing techniques,XQuery query processing techniques and XML-to-SQL query conversion techniques.Because of the importance of the structure connection algorithm in the XML query,we research and improve Parent/Child and Preceding-sibling/Following-sibling structural join algorithm that based on Breadth-Depth storage model proposed in this paper.In order to solve the problem that it's difficult for users to write inquiry expression,we propose the viewpoint that Construction of XML query expression using ontology model.At last,we apply the XML storage and query techniques to ancient architecture domain. A storage and query framework based on relational database is Constructed and detailed and in-depth analysis are carried on the implementation procedure.Then,based on features of ancient architecture, we put forward XML query optimization based on entire path and XML query optimization based on domain ontology.