A powerful visual formalism for XML data

XML data are data which are not necessary constrained by a schema, XML is fast emerging as a standard for data representation and exchange on the World Wide Web, the ability to intelligently query XML data becomes increasingly important. Some XML graphical query languages for XML data have been proposed but they are either too complex or too limited in use. In this paper we propose a recursive graphical query language for querying and restructuring XML data. The expressive power of RGQLX is comparable to Fixpoint. RGQLX language is a multi-sorted graphical language integrating grouping, aggregate functions, nested queries and recursion.