Introducing the aggregate "count" into flexible queries
نویسندگان
چکیده
Flexible querying aims at expressing preferences inside queries instead of strict requirements. We consider ordinary relational databases and flexible querying calling on fuzzy sets. The topic of this paper is to define new types of flexible conditions : the ones involving the count operator. The main difficulty is to handle cardinalities of fuzzy sets. keywords : databases, flexible querying, fuzzy sets, cardinalities of fizzy sets
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