Research And Improvement Of Storage Strategy For A NXD:dbXML

Native XML database is a research hot spot in the database fields home and abroad. How to store and index the XML document in the native XML database is an important issue. Firstly, the paper discusses the association ofXML and database, and dissertates three different storage ways in which an XML document is stored in the native XML database. Secondly, the paper gives the structure of the native XML database, and carefully studies on its indexing, querying, transaction, security, concurrency, and so on. Thirdly, the paper researches into dbXML which is a kind of open source native XML database, and deeply analyzes its multilayer storage model, and studies on its page storage strategy, the indexing structure of B+ tree, Compressed DOM tree and Document Table Storage Model. At last, to resolve the question which exists in the management of the free page, the paper brings forward two new strategies: tail page truncating strategy and page moving strategy, and implements them, which help dbXML release the disk space hold by the free page and optimize the utilizing rate of the disk resource.