Abstract
This paper studies queries to a database, involving expressions of the form ‘Q A-x’s are B’s’ where A and B are properties which may be fuzzy and with respect to which objects x’s are evaluated, and where Q is a quantifier which may stand for ‘all’, or may leave room for exceptions (‘at least q%’, ‘(at least) most’, etc.). An example of such a query is ‘Find the departments where most young employees are well-paid’. Such queries are discussed from a modeling and evaluation point of view, taking also into consideration what the user intends to ask when (s)he addresses this type of queries to a database system. Clarifying what has to be evaluated is specially important in the case where A is fuzzy, since then the boundaries of A are ill-defined and A may be somewhat empty.
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Bosc, P., Liétard, L., Prade, H. (1998). An Ordinal Approach to the Processing of Fuzzy Queries with Flexible Quantifiers. In: Hunter, A., Parsons, S. (eds) Applications of Uncertainty Formalisms. Lecture Notes in Computer Science(), vol 1455. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-49426-X_4
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DOI: https://doi.org/10.1007/3-540-49426-X_4
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