Multivalued Dependencies
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Multivalued dependency — In database theory, multivalued dependency is a full constraint between two sets of attributes in a relation. In contrast to the functional dependency, the multivalued dependency requires that certain tuples be present in a relation. Therefore, a … Wikipedia
Fourth normal form — (4NF) is a normal form used in database normalization. Introduced by Ronald Fagin in 1977, 4NF is the next level of normalization after Boyce Codd normal form (BCNF). Whereas the second, third, and Boyce Codd normal forms are concerned with… … Wikipedia
Database normalization — In the design of a relational database management system (RDBMS), the process of organizing data to minimize redundancy is called normalization. The goal of database normalization is to decompose relations with anomalies in order to produce… … Wikipedia
Dependency theory (database theory) — Dependency theory is a subfield of database theory which studies implication and optimization problems related to logical constraints, commonly called dependencies, on databases. The best known class of such dependencies are functional… … Wikipedia
MVD — Motor Vehicle Division (Governmental) *** Montevideo, Uruguay (Regional » Airport Codes) ** Music Video Distributors (Business » Firms) ** Motor Vehicle Dealer (Business » Positions) ** Motor Vehicle Dealer (Business » Firms) * MicroVision… … Abbreviations dictionary
MVD — comp. abbr. Multivalued Dependencies … United dictionary of abbreviations and acronyms
Functional dependency — A functional dependency (FD) is a constraint between two sets of attributes in a relation from a database.Given a relation R , a set of attributes X in R is said to functionally determine another attribute Y , also in R , (written X → Y ) if and… … Wikipedia
