Characterizations of Multivalued Dependencies and Related Expressions
نویسندگان
چکیده
We study multivalued dependencies, as well as the propositional formulas whose deduction calculus parallels that of multivalued dependencies, and the variant known as degenerated multivalued dependencies. For each of these sorts of expressions, we provide intrinsic characterizations in purely semantic terms. They naturally generalize similar properties of functional dependencies or Horn clauses.
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