A Store And Query System Design Of XML Based On Relation Database

The appearance and development of Internet and Web have widened the living space of human being influenced the life style greatly ,and Web is becoming a prime vehicle for getting, disseminating and exchanging information. With the explosion of information on the Web . Extensible Markup Language(XML),which is approved by W3C (World Wide Web Consortium)in 1998,will be used as substitute for HTML standard in the near future . XML is the bridge between Web and database. Web information can be turned into a database by the format of XML. The thesis researches some techniques of XML databases from the Database viewpoint .It concentrates on the following issues:data models ,storage management, schema management,query processing.In this thesis, a XRDB system was design for study the issues,XRDB system is a XML storage and query system and relation Database as it's physical store stucture . the feature of XRDB system is follow: The relation of XML element and it's son is keeped by relation -dictionary,as the same time the relation-dictionary keeped the element attributes,content and their corresponding in relation database. In order to get the more efficiency relation table, the DOM tree of XML Schema is trimed for getting orderliness XML Schema. For efficiency rewrited path expression into SQL, the relation dictionary keeps every XML element's absolute path. The quary's result of the XRDB is the former XML document segment.