Efficient Handling of Positional Predicates Within XML Query Processing

  • Zografoula Vagena
  • Nick Koudas
  • Divesh Srivastava
  • Vassilis J. Tsotras
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3671)


The inherent order within the XML document-centric data model is typically exposed through positional predicates defined over the XPath navigation axes. Although processing algorithms for each axis have already been proposed, the incorporation of positional predicates in them has received very little attention. In this paper, we present techniques that leverage the power of existing, state of the art methods, to efficiently support positional predicates as well. Our preliminary experimental comparisons with alternative approaches reveal the performance benefits of the proposed techniques.


Query Node Naive Algorithm XPath Query Context Node Element List 
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 2005

Authors and Affiliations

  • Zografoula Vagena
    • 1
  • Nick Koudas
    • 2
  • Divesh Srivastava
    • 3
  • Vassilis J. Tsotras
    • 1
  1. 1.UC Riverside 
  2. 2.University of Toronto 
  3. 3.AT&T Labs-Research 

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