Reasoning about Keys for XML

  • Peter Buneman
  • Susan Davidson
  • Wenfei Fan
  • Carmem Hara
  • Wang-Chiew Tan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2397)


We study absolute and relative keys for XML, and investigate their associated decision problems. We argue that these keys are important to many forms of hierarchically structured data including XML documents. In contrast to other proposals of keys for XML, these keys can be reasoned about efficiently. We show that the (finite) satisfiability problem for these keys is trivial, and their (finite) implication problem is finitely axiomatizable and decidable in PTIME in the size of keys.


Inference Rule Regular Language Path Expression Semistructured Data 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 2002

Authors and Affiliations

  • Peter Buneman
    • 1
  • Susan Davidson
    • 1
  • Wenfei Fan
    • 2
  • Carmem Hara
    • 3
  • Wang-Chiew Tan
    • 1
  1. 1.University of PennsylvaniaPhiladelphiaUSA
  2. 2.Bell LaboratoriesMurray HillUSA
  3. 3.Universidade Federal do ParanaCuritiba, PRBrazil

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