On the interpretation of set-oriented fuzzy quantified queries and their evaluation in a database management system
Many propositions to extend database management systems have been made in the last decade. Some of them aim at the support of a wider range of queries involving fuzzy predicates. Unfortunately, the evaluation of these queries is computationally complex and efficiency is considered in this paper. We focus on a particular subset of queries, namely those using fuzzy quantified predicates. More precisely, we will consider the case where such predicates apply to sets of elements. Based on some interesting properties of α-cuts of fuzzy sets, we are able to show that the evaluation of these queries can be significantly improved with respect to a naïve strategy performing exhaustive scans of sets.
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