| Natural Join | a join in which the redundant logic components generated by the join are removed. |
| Network Model | a data model that provides data relationships on the basis of records or groups of records (ie. sets) in which one record is designated as the set owner, and a single member record can belong to one or more sets. |
| Nonprocedural Language | syntax that directs the computer as to what to do, not how to do it. Typical nonprocedural languages include RAMIS,FOCUS, NOMAD, and SQL. |
| Normalization | Normalization is a step-by-step process of removing redundancies and dependencies of attributes in a data structure. The condition of the data at completion of each step is described as a "normal form." Thus, when normalizing we talk about data as being in the first normal form, the second normal form, etc. Normalization theory identifies normal forms up to at least the fifth normal form, plus an adjunct form known as Boyce-Codd Normal Form (BCNF). The first three forms are sufficient to meet the needs of warehousing data models. |
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