Data Model and Query Constructs for Versatile Web Query Languages: State-of-the-Art and Challenges for Xcerpt

  • François Bry
  • Tim Furche
  • Benedikt Linse
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4187)


As the Semantic Web is gaining momentum, the need for truly versatile query languages becomes increasingly apparent. A Web query language is called versatile if it can access in the same query program data in different formats (e.g. XML and RDF). Most query languages are not versatile: they have not been specifically designed to cope with both worlds, providing a uniform language and common constructs to query and transform data in various formats. Moreover, most mainstream query languages do not provide a flexible data model that is powerful enough to naturally convey both Semantic Web data formats (especially RDF and Topic Maps) and XML. This article highlights challenges related to the data model and language constructs for querying both standard Web and Semantic Web data with an emphasis on facilitating sophisticated reasoning. It is shown that Xcerpt’s data model and querying constructs are particularly well-suited for the Semantic Web, but that some adjustments of the Xcerpt syntax allow for even more effective and natural querying of RDF.


Query Language Query Term Query Pattern Blank Node Query Construct 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • François Bry
    • 1
  • Tim Furche
    • 1
  • Benedikt Linse
    • 1
  1. 1.Institute for InformaticsUniversity of MunichMünchenGermany

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