A Calculus for Fuzzy Queries on Fuzzy Entity-Relationship Model
نویسنده
چکیده
Most query languages are designed to retrieve information from databases containing precise and certain data using precisely specified commands. Application of fuzzy set theory to relational data models has been studied extensively in recent years. This paper presents a calculus for fuzzy queries on a fuzzy entity-relationship model. The paper, first, defines a fuzzy entity-relationship model capable of representing imprecision and uncertainty in entities, attributes, and relationships. Then, it describes a calculus for fuzzy queries along with operational semantics. Some of the key aspects of this calculus are the provision of multiple terms, aggregate functions, and various forms of quantification.
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