Fuzzy Database Query Languages and Their Relational Completeness Theorem

  title={Fuzzy Database Query Languages and Their Relational Completeness Theorem},
  author={Yoshikane Takahashi},
  journal={IEEE Trans. Knowl. Data Eng.},
  • Y. Takahashi
  • Published 1 February 1993
  • Computer Science
  • IEEE Trans. Knowl. Data Eng.
Two fuzzy database query languages are proposed. They are used to query fuzzy databases that are enhanced from relational databases in such a way that fuzzy sets are allowed in both attribute values and truth values. A fuzzy calculus query language is constructed based on the relational calculus, and a fuzzy algebra query language is also constructed based on the relational algebra. In addition, a fuzzy relational completeness theorem such that the languages have equivalent expressive power is… 
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