Promoting the Semantic Capability of XML Keys

  • Flavio Ferrarotti
  • Sven Hartmann
  • Sebastian Link
  • Jing Wang
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6309)


Keys for XML data trees can uniquely identify nodes based on the data values on some of their subnodes, either in the entire tree or relatively to some selected subtrees. Such keys have an impact on several XML applications. A challenge is to identify expressive classes of keys with good computational properties. In this paper, we propose such a new class of keys. In comparison to previous work, the new class of XML keys is defined using a more expressive navigational path language that allows the specification of single-label wildcards. This provides designers with an enhanced ability to capture properties of XML data that are significant for the application at hand. We establish a sound and complete set of inference rules that characterizes all keys that are implicit in the explicit specification of XML keys. Furthermore, we establish an efficient algorithm for deciding XML key implication.


Inference Rule Path Expression Contact Node Document Object Model Implication Problem 
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 2010

Authors and Affiliations

  • Flavio Ferrarotti
    • 1
  • Sven Hartmann
    • 2
  • Sebastian Link
    • 1
  • Jing Wang
    • 3
  1. 1.Victoria University of WellingtonNew Zealand
  2. 2.Clausthal University of TechnologyGermany
  3. 3.Massey UniversityNew Zealand

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