Encyclopedia of Database Systems

2018 Edition
| Editors: Ling Liu, M. Tamer Özsu

XML Types

  • Frank Neven
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-8265-9_1563

Synonyms

XML schemas

Definition

To constrain the structure of allowed XML documents, for instance with respect to a specific application, a target schema can be defined in some schema language. A schema consists of a sequence of type definitions specifying a (possibly infinite) class of XML documents. A type can be assigned to every element in a document valid w.r.t. a schema. As the same holds for the root element, the document itself can also be viewed to be of a specific type. The schema languages DTDs, XML Schema, and Relax NG, are, on an abstract level, different instantiations of the abstract model of unranked regular tree languages.

Historical Background

Brüggemann-Klein et al. [3] were the first to revive the theory of regular unranked tree automata [14] for the modelling of XML schema languages. Murata et al. [10] provided the formal taxonomy as presented here. Martens et al. [8] characterized the expressiveness of the different models and provided type-free abstractions.

Foundations...

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Recommended Reading

  1. 1.
    Brüggemann-Klein A. Regular expressions into finite automata. Theor Comput Sci. 1993;120(2): 197–213.MathSciNetzbMATHCrossRefGoogle Scholar
  2. 2.
    Brüggemann-Klein A, Wood D. One unambiguous regular languages. Inf Comput. 1998;140(2): 229–53.MathSciNetzbMATHCrossRefGoogle Scholar
  3. 3.
    Brüggemann-Klein A, Murata M, Wood D. Regular tree and regular hedge languages over unranked alphabets. Technical report HKUST-TCSC-2001-0. The Hongkong University of Science and Technology; 2001.Google Scholar
  4. 4.
    Carme J, Niehren J, Tommasi M. Querying unranked trees with stepwise tree automata. In: Proceedings of the 15th International Conference on Rewriting Techniques and Applications; 2004. p. 105–18.CrossRefGoogle Scholar
  5. 5.
    Cristau J, Löding C, Thomas W. Deterministic automata on unranked trees. In: Proceedings of the 15th International Symposium on Fundamentals of Computation Theory; 2005. p. 68–79.CrossRefGoogle Scholar
  6. 6.
    Hosoya H, Murata M. Boolean operations and inclusion test for attribute-element constraints. Theor Comput Sci. 2006;360(1–3):327–51.MathSciNetzbMATHCrossRefGoogle Scholar
  7. 7.
    Martens W, Niehren J. Minimizing tree automata for unranked trees. In: Proceedings of the 10th International Workshop on Database Programming Languages; 2005. p. 232–46.CrossRefGoogle Scholar
  8. 8.
    Martens W, Neven F, Schwentick T, Bex GJ. Expressiveness and complexity of XML schema. ACM Trans Database Syst. 2006;31(3):770–813.CrossRefGoogle Scholar
  9. 9.
    Martens W, Neven F, Schwentick T. Simple off the shelf abstractions for XML schema. ACM SIGMOD Rec. 2007;36(4):15–22.CrossRefGoogle Scholar
  10. 10.
    Murata M, Lee D, Mani M, Kawaguchi K. Taxonomy of XML schema languages using formal language theory. ACM Trans Internet Technol. 2005;5(4):660–704.CrossRefGoogle Scholar
  11. 11.
    Neven F. Automata theory for XML researchers. ACM SIGMOD Rec. 2002;31(3):39–46.CrossRefGoogle Scholar
  12. 12.
    Neven F, Schwentick T. Query automata on finite trees. Theor Comput Sci. 2002;275:633–74.MathSciNetzbMATHCrossRefGoogle Scholar
  13. 13.
    Segoufin L, Vianu V. Validating streaming XML documents. In: Proceedings of the 21st ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems; 2002. p. 53–64.Google Scholar
  14. 14.
    Thatcher JW. Characterizing derivation trees of context-free grammars through a generalization of finite automata theory. J Comput Syst Sci. 1967;1(4):317–22.MathSciNetzbMATHCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Hasselt University and Transnational University of LimburgDiepenbeekBelgium

Section editors and affiliations

  • Sihem Amer-Yahia
    • 1
  1. 1.Laboratoire d'Informatique de GrenobleCNRS and LIGGrenobleFrance