XML Data Index And Optimization

In recent years, with the continuous development of the Internet, data switching is becoming frequent. Because the XML has the characteristics of description and transplant, making it an important data switching standard in the commercial, industrial, and life.The XML data is increasing constantly, because of XML is used. So there has a problem about query efficiency. How to solve that problem has been the hot problem. Although the scholars proposed a lot of algorithms for imposing the efficiency of query, such as based on buffer memory, coding and so on,these algorithms have some defects respectively. In this paper, we study XML query deeply, and we also elaborate the problem about XML data management, XML data coding and query. At last, we proposed two algorithms for imposing the XML query efficiency---FC-index and FSM:(1) The query algorithm FC-Index supporting mergingFor imposeing XML query efficiency, the key of the question is avoiding to query the irrespective elements.By combining the elements,the number of the elements can be reduced,and we can avoid to query the redundant elements for querying quickly and correctly.In our article,a new efficient index structure—FC-Index based on Ctree is proposed to leach the irrespective elements in the querying.At the same time,we also propose a new query algorithm based on FC-Index which can improve the query's performance significantly for FC-Index.(2) The query algorithm FSM supporting filteringMatching XML which is by scanning repeatedly can make a lot of middle routes in the process of merging; the XML datasets is too uncertain to impose the efficiency of query well by filtering. In our article, a new efficient index structure—FSM is proposed, and it can avoid merging the unnecessary routes, and impose the efficiency of filtering. Through a lot of experiments, the efficiency of FSM is better than the former ones, and FSM also impose the efficiency of query.In short, we propose two algorithms which support filtering and avoiding merging the unnecessary routes respectively for the defects. Through a lot of experiments, the algorithms can impose the efficiency of query.