Subsumption for XML Types

  • Gabriel M. Kuper
  • Jérôme Siméon
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1973)


XML data is often used (validated, stored, queried, etc) with respect to different types. Understanding the relationship between these types can provide important information for manipulating this data. We propose a notion of subsumption for XML to capture such relationships. Subsumption relies on a syntactic mapping between types, and can be used for facilitating validation and query processing. We study the properties of subsumption, in particular the notion of the greatest lower bound of two schemas, and show how this can be used as a guide for selecting a storage structure. While less powerful than inclusion, subsumption generalizes several other mechanisms for reusing types, notably extension and refinement from XML Schema, and subtyping.


Type System Query Processing Regular Expression Query Language Type Assignment 
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 2001

Authors and Affiliations

  • Gabriel M. Kuper
    • 1
  • Jérôme Siméon
    • 1
  1. 1.Bell LaboratoriesNJUSA

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