Fuzzy XQuery

Traditional database systems and languages are very rigid. XML data and query languages are not the exception. Fuzzy set theory is an appropriate tool for solving this problem. In this sense, Fuzzy XQuery was proposed as an extension of the XQUERY standard. This language defines the xs:truth datatype, the xml:truth attribute and allows the definition and use of fuzzy terms in queries. The main goal of this chapter is to show a high coupling implementation of Fuzzy XQuery within eXist-db, an open source XML DBMS. This extension strategy could also be used with other similar tools. This chapter also presents a statistical performance analysis of the extended fuzzy query engine using the XMark benchmark with user defined fuzzy terms. The study presents promising results.