Towards Aggregated Answers for Semistructured Data

  • Holger Meuss
  • Klaus U. Schulz
  • François Bry
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1973)

Abstract

Semistructured data [5],[34],[23],[31],[1] are used to model data transferred on the Web for applications such as e-commerce [18], biomolecular biology [8], document management [2],[21], linguistics [32], thesauri and ontologies [17]. They are formalized as trees or more generally as (multi-)graphs [23],[1]. Query languages for semistructured data have been proposed [6],[11],[1],[4],[10] that, like SQL, can be seen as involving a number of variables [35], but, in contrast to SQL, give rise to arrange the variables in trees or graphs reflecting the structure of the semi- structured data to be retrieved. Leaving aside the “construct” parts of queries, answers can be formalized as mappings represented as tuples, hence called an- swer tuples, that assign database nodes to query variables. These answer tuples underly the semistructured data delivered as answers.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Holger Meuss
    • 1
  • Klaus U. Schulz
    • 1
  • François Bry
    • 2
  1. 1.CIS, University of MunichMunichGermany
  2. 2.Institute for Computer ScienceUniversity of MunichMunichGermany

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