An Abstract Framework for Generating Maximal Answers to Queries

  • Sara Cohen
  • Yehoshua Sagiv
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3363)

Abstract

A framework for modeling query semantics as graph properties is presented. In this framework, a single definition of a query automatically gives rise to several semantics for evaluating that query under varying degrees of incomplete information. For example, defining natural joins automatically gives rise to full disjunctions. Two of the proposed semantics have incremental-polynomial-time query-evaluation algorithms for all types of queries that can be defined in this framework. Thus, the proposed framework generalizes previous definitions of semantics for incomplete information and improves previous complexity results for query evaluation.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Sara Cohen
    • 1
  • Yehoshua Sagiv
    • 2
  1. 1.Faculty of Industrial Engineering and ManagementTechnion—Israel Institute of Technology, Technion CityHaifaIsrael
  2. 2.The Selim and Rachel Benin School of Engineering and Computer ScienceThe Hebrew University of JerusalemJerusalemIsrael

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