An O(N2) equivalence algorithm for fan-out free queries

  • Pratul Dublish
  • S. N. Maheshwari
Complexity And Optimization
Part of the Lecture Notes in Computer Science book series (LNCS, volume 326)


An equivalence algorithm for fan-out free queries, which form an untyped subclass of conjunctive queries, based on an extension of the implication graph technique is presented. This algorithm runs in O(n2) time where n is the size of the queries involved. This algorithm subsumes all known equivalence testing algorithms for various subclasses of fan-out free queries.


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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • Pratul Dublish
    • 1
  • S. N. Maheshwari
    • 1
  1. 1.Department of Computer Science & EngineeringIndian Institute of TechnologyDelhi New DelhiIndia

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