An ordinal approach to the processing of fuzzy queries with flexible quantifiers

International audienceThis 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