Research Of XML Data Model Based On Fuzzy Data

The traditional XML has not been able to meet the demands of application in reality, for there are a lot of inaccurate and uncertain information in daily life. Therefore, the XML data model based on fuzzy data has been widely studied in recent years. It is well known that XML data management technology is mainly composed of four modules, including data storage, indexing, structure connecting and query. The traditional XML indexing and structure connecting technology is still applicable to the XML document with fuzzy data, as the fuzziness of data is embodied in content rather than the structure. At present, the current issues are mainly the specification of fuzzy data in syntactic parser, the coding scheme of XML document containing fuzzy data and the query with fuzzy statements by users. Moreover, only when the data is defined correctly, can the document be able to code and store, and finally realize the function of data query.So far, the data specification of the parser has made a certain achievement, it has completed the improvement of the parser namely DTD. However, there are many shortages in DTD. So this paper proposes the new modifications of the parser XML Schema in order to solve this problem. It is defined into two classes in XML Schema according the characteristics of fuzzy data, so as to improve the parser functions and realize the definition of fuzzy data in XML. On the basis, this paper proposes a new kind of coding scheme to encode the fuzzy elements in the XML document by using a quadruple. First and foremost, each document will be given a serial number, and the elements in the same document have the same serial number; secondly, we can take preorder traversal for the entire document tree, and record the start number and the end number. Though the two parameters, the structure relations of different nodes can be judged, then record the fuzziness of nodes with a prefix way; finally, each element would be set a group mark to judge their brother nodes. For the fuzzy query, the first step is to construct the membership function, and then elaborate them according the threshold, eventually, the query results would be sorting. In addition, this paper designs an experiment to finish the function of query by random fuzzy sets and the new coding scheme.In the experiment, the function of data storage has been completed through the new coding scheme, and the queries with some fuzzy statements by users have also been solved. At the end of the experiment, the results given to users are more relative to the requirements. The experimental results show that the method above can be effective to encode XML document containing fuzzy data, and users can adjust the threshold to get results which are closer to the expectations.