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Towards a Basic Relational NF2 Algebra Processor

  • H.-J. Schek

Abstract

Relations with relation-valued attributes (NF2 relations) are proposed to serve as a model for internal data structures of a data base system. A related NF2 relational algebra is described and a suitable subset of it is selected to define the interface of a basic NF2 algebra processor. It will be shown that specific projection-selection-join-sequences expressed in 1NF relations at the conceptual level are mapped to nested projection-selection sequences of the internal of NF2 relations. Costly joins therefore can be eliminated and substituted by equivalent cheaper linear queries. The selection of the subset of NF2 algebra operations is motivated by this join elimination and by the restriction to single-scan operations.

Keywords

Conceptual Level Relational Algebra Address Space Nest Selection Access Path 
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

© Plenum Press, New York 1987

Authors and Affiliations

  • H.-J. Schek
    • 1
  1. 1.Technical University of DarmstadtDarmstadtWest Germany

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