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Avoiding Unnecessary Ordering Operations in XPath

  • Jan Hidders
  • Philippe Michiels
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2921)

Abstract

We present a sound and complete rule set for determining whether sorting by document order and duplicate removal operations in the query plan of XPath expressions are unnecessary. Additionally we define a deterministic automaton that illustrates how these rules can be translated into an efficient algorithm. This work is an important first step in the understanding and tackling of XPath/XQuery optimization problems that are related to ordering and duplicate removal.

Keywords

Inference Rule Formal Semantic Query Plan Path Expression XPath Expression 
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 2004

Authors and Affiliations

  • Jan Hidders
    • 1
  • Philippe Michiels
    • 1
  1. 1.Dept. of Mathematics and Computer ScienceUniversity of AntwerpAntwerpenBelgium

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