second normal form
Смотреть что такое "second normal form" в других словарях:
Second normal form — (2NF) is a normal form used in database normalization. 2NF 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 Base Systems, New… … Wikipedia
Second fundamental form — In differential geometry, the second fundamental form is a quadratic form on the tangent plane of a smooth surface in the three dimensional Euclidean space, usually denoted by II. Together with the first fundamental form, it serves to define… … Wikipedia
First normal form — (1NF or Minimal Form) is a normal form used in database normalization. A relational database table that adheres to 1NF is one that meets a certain minimum set of criteria. These criteria are basically concerned with ensuring that the table is 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
Normal-form game — In game theory, normal form is a way of describing a game. Unlike extensive form, normal form representations are not graphical per se, but rather represent the game by way of a matrix. While this approach can be of greater use in identifying… … 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
Jordan normal form — In linear algebra, a Jordan normal form (often called Jordan canonical form)[1] of a linear operator on a finite dimensional vector space is an upper triangular matrix of a particular form called Jordan matrix, representing the operator on some… … Wikipedia
Skolem normal form — A formula of first order logic is in Skolem normal form (named after Thoralf Skolem) if it is in conjunctive prenex normal form with only universal first order quantifiers. Every first order formula can be converted into Skolem normal form while… … 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
Greibach normal form — In computer science, to say that a context free grammar is in Greibach normal form (GNF) means that all production rules are of the form::A o alpha X or:S o lambdawhere A is a nonterminal symbol, α is a terminal symbol, X is a (possibly empty)… … Wikipedia
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
