- Boyce-Codd normal form
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A stage in the normalization of a relational database in which a database is in third normal form and all determinants are candidate keys.
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Boyce-Codd normal form
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Boyce-Codd normal form — (or BCNF) is a normal form used in database normalization. It is a slightly stronger version of the third normal form (3NF). A table is in Boyce Codd normal form if and only if, for every one of its non trivial functional dependencies X → Y , X… … Wikipedia
Domain/key normal form — (DKNF) is a normal form used in database normalization which requires that the database contains no constraints other than domain constraints and key constraints. A domain constraint specifies the permissible values for a given attribute, while a … Wikipedia
Third normal form — The third normal form (3NF) is a normal form used in database normalization. 3NF was originally defined by E.F. CoddCodd, E.F. Further Normalization of the Data Base Relational Model. (Presented at Courant Computer Science Symposia Series 6, Data … 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
fifth normal form — noun A stage in the normalization of a relational database in which a database is in fourth normal form and every join dependency is implied by the candidate keys. See Also: first normal form … Wiktionary
second normal form — noun A stage in the normalization of a relational database in which it is in first normal form and every non key attribute is dependent upon the entire primary key. See Also: first normal form … Wiktionary
third normal form — noun A stage in the normalization of a relational database in which a database is in second normal form and all non key attributes are mutually independent (no transient dependencies.) See Also … Wiktionary
fourth normal form — noun A stage in the normalization of a relational database in which a database is in Boyce Codd normal form and all multi valued dependencies are functional dependencies. See Also: first normal form, second normal form, third normal form … Wiktionary
first normal form — noun A stage in the normalization of a relational database in which repeating groups and attributes have been eliminated by putting each into a separate table connected by a primary key foreign key relationship. See Also: second normal form … Wiktionary
Boyce-Codd-Normalform — Dieser Artikel oder Abschnitt bedarf einer Überarbeitung. Näheres ist auf der Diskussionsseite angegeben. Hilf mit, ihn zu verbessern, und entferne anschließend diese Markierung. Unter Normalisierung eines relationalen Datenbankschemas versteht… … Deutsch Wikipedia
