XPath Containment in the Presence of Disjunction, DTDs, and Variables

  • Frank Neven
  • Thomas Schwentick
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2572)


XPath is a simple language for navigating an XML tree and returning a set of answer nodes. The focus in this paper is on the complexity of the containment problem for various fragments of XPath. In addition to the basic operations (child, descendant, filter, and wildcard), we consider disjunction, DTDs and variables. W.r.t. variables we study two semantics: (1) the value of variables is given by an outer context; (2) the value of variables is defined existentially.We establish an almost complete classification of the complexity of the containment problem w.r.t. these fragments.


Regular Expression Disjunctive Normal Form Tree Automaton Containment Testing 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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  1. 1.
    M. Benedikt, W. Fan, and G. M. Kuper. Structural properties of XPath fragments. ICDT 2003, this volume.Google Scholar
  2. 2.
    G. J. Bex, S. Maneth, and F. Neven. A formal model for an expressive fragment of XSLT. Information Systems, 27(1):21–39, 2002.zbMATHCrossRefGoogle Scholar
  3. 3.
    D. Chamberlin, J. Clark, D. Florescu, J. Robie, J. Simeon, and M. Stefanascu. XQuery 1.0: An XML query language., 2002.
  4. 4.
    B. S. Chlebus. Domino-tiling games. Journal of Computer and System Sciences, 32(3):374–392, 1986.zbMATHCrossRefMathSciNetGoogle Scholar
  5. 5.
    J. Clark. XML Path Language (XPath).
  6. 6.
    James Clark. XSL transformations version 1.0., August 1999.
  7. 8.
    S. DeRose, E. Maler, and R. Daniel. XML pointer language (XPointer) version 1.0., 2001.
  8. 9.
    S. DeRose, E. Maler, and D. Orchard. XML linking language (XLink) version 1.0., 2001.
  9. 10.
    A. Deutsch and V. Tannen. Containment and integrity constraints for xpath. In Maurizio Lenzerini, Daniele Nardi, Werner Nutt, and Dan Suciu, editors, Proceedings of the 8th International Workshop on Knowledge Representation meets Databases (KRDB 2001), number 45 in CEUR Workshop Proceedings, 2001.Google Scholar
  10. 11.
    G. Gottlob and C. Koch. Monadic queries over tree-structured data. In Proc. 17th IEEE Symposium on Logic in Computer Science (LICS 2002), 2002.Google Scholar
  11. 12.
    G. Gottlob, C. Koch, and R. Pichler. Efficient algorithms for processing XPath queries. In Proc. of 28th Conf. on VLDB, 2002.Google Scholar
  12. 13.
    J.E. Hopcroft and J.D. Ullman. Introduction to Automata Theory, Languages, and Computation. Addison-Wesley, 1979.Google Scholar
  13. 14.
    G. Miklau and D. Suciu. Containment and equivalence for an XPath fragment. In Proc. 21th Symposium on Principles of Database Systems (PODS 2002), pages 65–76, 2002.Google Scholar
  14. 15.
    G. Moerkotte. Incorporating XSL processing into database engines. In Proc. of 28th Conf. on VLDB, 2002.Google Scholar
  15. 16.
    F. Neven. Automata, logic, and XML. In J. C. Bradfield, editor, CSL, volume 2471 of Lecture Notes in Computer Science, pages 2–26. Springer, 2002.Google Scholar
  16. 17.
    F. Neven. Automata theory for XML researchers. SIGMOD Record, 31(3), 2002.Google Scholar
  17. 18.
    F. Neven and T. Schwentick. Automata-and logic-based pattern languages for tree-structured data. Unpublished, 2001.Google Scholar
  18. 19.
    F. Neven and T. Schwentick. Query automata on finite trees. Theoretical Computer Science, 275:633–674, 2002.zbMATHCrossRefMathSciNetGoogle Scholar
  19. 20.
    G. Slutzki. Alternating tree automata. Theoretical Computer Science, 41(2-3):305–318, 1985.zbMATHCrossRefMathSciNetGoogle Scholar
  20. 21.
    P. T. Wood. Containment for XPath fragments under DTD constraints. ICDT 2003, this volume.Google Scholar
  21. 22.
    P. T. Wood. Minimising simple XPath expressions. WebDB informal proceedings, 2001.Google Scholar
  22. 23.
    P. T. Wood. On the equivalence of XML patterns. In Lloyd et al., editor, Computational Logic — CL 2000, volume 1861 of Lecture Notes in Artificial Intelligence, pages 1152–1166. Springer, 2000.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Frank Neven
    • 1
  • Thomas Schwentick
    • 2
  1. 1.University of LimburgLimburg
  2. 2.Philipps-Universität MarburgUSA

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