On flexible database querying via extensions to fuzzy sets
نویسندگان
چکیده
In search of semantic richer and more flexible database modelling and database querying techniques, different approaches based on fuzzy set theory have been developed. Among the most successful approaches are the possibilistic and similarity based models. More recently, extended possibilistic logic and various extensions to fuzzy sets have been applied to further enrich flexible database models. In this paper it is presented how ‘IS’ predicates in flexible queries can be evaluated in the presence of data that is modelled by such extensions to fuzzy sets. Furthermore, a comparison with the regular possibilistic database modelling approach is given.
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