Problems of fuzzy queries involving aggregation functions: the "select count" case

This paper deals with the problem of solving flexible queries made to relational databases, where the target of a query is not a list of attributes but any kind of summary function which is applied either to one attribute or to the whole table. In particular, we attempt to solve questions which imply a generalization of the select count sentence. We consider as general a context as possible, by assuming: the involved table includes fuzzy attributes, and the property which makes the selection, generates a fuzzy set of tuples