A survey of graphical query languages for XML data

XML is fast emerging as the dominant standard for information exchange on the World Wide Web. The ability to intelligently query XML data becomes increasingly important. Several query languages are proposed in the literature, some of them are textual query languages and some others are graphical query languages. In this article, we will survey some of graphical query languages for querying and restructuring XML data. Also, we will conduct a comparative study between these languages based on a set of requirements and features that an XML query language should have.