Data Tables with Similarity Relations: Functional Dependencies, Complete Rules and Non-redundant Bases
نویسندگان
چکیده
We study rules A ⇒ B describing attribute dependencies in tables over domains with similarity relations. A ⇒ B reads “for any two table rows: similar values of attributes from A imply similar values of attributes from B”. The rules generalize ordinary functional dependencies in that they allow for processing of similarity of attribute values. Similarity is modeled by reflexive and symmetric fuzzy relations. We show a system of Armstrong-like derivation rules and prove its completeness (two versions). Furthermore, we describe a non-redundant basis of all rules which are true in a data table and present an algorithm to compute bases.
منابع مشابه
Functional Dependencies of Data Tables Over Domains with Similarity Relations
We study attribute dependencies in a setting of fuzzy logic. Our dependencies are described by formulas A ⇒ B where A and B are fuzzy sets of attributes. The meaning of A ⇒ B is that any two objects that have similar values on attributes from A have also similar values on attributes from B. Our approach generalizes classical functional dependencies from databases and also several approaches to ...
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