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Scalar Aggregation in FD-Inconsistent Databases

  • Marcelo Arenas
  • Leopoldo Bertossi
  • Jan Chomicki
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1973)

Abstract

We consider here scalar aggregation queries in databases that may violate a given set of functional dependencies. We show how to compute consistent answers (answers true in every minimal repair of the database) to such queries. We provide a complete characterization of the computational complexity of this problem. We also show how tractability can be obtained in several special cases (one involves a novel application of the perfect graph theory) and present a practical hybrid query evaluation method.

Keywords

Maximum Clique Integrity Constraint Perfect Graph Database Instance Consistent Answer 
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

  • Marcelo Arenas
    • 1
  • Leopoldo Bertossi
    • 2
  • Jan Chomicki
    • 3
  1. 1.Department of Computer ScienceUniversity of Toronto
  2. 2.Escuela de Ingeniería, Departamento de Ciencia de ComputacionPontificia Universidad Catolica de ChileChile
  3. 3.Department of Computer Science and EngineeringUniversity at BuffaloUSA

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