The growing acceptance of XML as a standard for send-structured documents on the Web opens up challenging opportunities for Web query languages. In this paper we introduce XML-GL, a graphical query language for XML documents. The use of a visual formalism for representing both the content of XML documents (and of their DTDs) and the syntax and semantics of queries enables an intuitive expression of queries, even when they are rather complex. XML-GL is inspired by G-log, a general purpose, logic-based language for querying structured and send-structured data. The paper presents the basic capabilities of XML-GL through a sequence of examples of increasing complexity.
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