Search results
Results from the WOW.Com Content Network
In contrast, the 5NF design excludes the possibility of such inconsistencies. A table T is in fifth normal form (5NF) or projection-join normal form (PJ/NF) if it cannot have a lossless decomposition into any number of smaller tables. The case where all the smaller tables after the decomposition have the same candidate key as the table T is ...
Database normalization is the process of structuring a relational database in accordance with a series of so-called normal forms in order to reduce data redundancy and improve data integrity.
Denormalization is a strategy used on a previously-normalized database to increase performance. In computing, denormalization is the process of trying to improve the read performance of a database, at the expense of losing some write performance, by adding redundant copies of data or by grouping data.
In database normalization, unnormalized form (UNF or 0NF), also known as an unnormalized relation or non-first normal form (N1NF or NF 2), [1] is a database data model (organization of data in a database) which does not meet any of the conditions of database normalization defined by the relational model.
Essential tuple normal form (ETNF) is a normal form used in database normalization.It lies strictly between fourth normal form (4NF) and fifth normal form (5NF). As per the original paper, ETNF, although strictly weaker than 5NF, is exactly as effective as 5NF in eliminating redundancy of tuples.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
A database management system (DBMS) is a computer program (or more typically, a suite of them) designed to manage a database, a large set of structured data, and run operations on the data requested by numerous users. Typical examples of DBMS use include accounting, human resources and customer support systems.
Domain-key normal form (DK/NF or 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 key constraint specifies the attributes that uniquely identify a ...