Unnesting Fuzzy SQL Queries in Fuzzy Databases

  • Qi Yang
  • Weining Zhang
  • Chenjie Luo
  • Clement Yu
  • H. Nakajima
Conference paper
Part of the Workshops in Computing book series (WORKSHOPS COMP.)


The efficiency of processing fuzzy queries in fuzzy databases is a major concern. We provide techniques to unnest fuzzy queries (of two blocks) of type N, type J, type JA, and nested queries with quantifiers. We show that by unnesting the queries, efficiency can be improved significantly. The results obtained in the paper form the basis for unnesting fuzzy queries of arbitrary blocks in fuzzy databases.


Main Memory Membership Degree Fuzzy Relation Satisfaction Degree Original Query 
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

© British Computer Society 1994

Authors and Affiliations

  • Qi Yang
    • 1
  • Weining Zhang
    • 1
  • Chenjie Luo
    • 1
  • Clement Yu
    • 1
  • H. Nakajima
    • 1
  1. 1.Department of EECSUniversity of Illinois at Chicago, Omron CorporationKyoto 617Japan

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