Testing containment of object-oriented conjunctive queries is ∏2p-hard

  • Edward P. F. Chan
  • Ron van der Meyden
Session 2B: Database
Part of the Lecture Notes in Computer Science book series (LNCS, volume 959)


We study the complexity of testing containment for a class of object-oriented conjunctive queries. We show that the containment problem is ∏ 2 p -hard. Together with a previous result, the containment problem is complete in ∏ 2 p .


Normal Form Atomic Type Truth Table Query Optimization Conjunctive Query 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Edward P. F. Chan
    • 1
  • Ron van der Meyden
    • 2
  1. 1.Department of Computer ScienceUniversity of WaterlooWaterlooCanada
  2. 2.Information Science LaboratoryNTT Basic Research LaboratoriesKanagawaJapan

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