National Change of Address - NCOA
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Negation
Specifying that a query is to select all records except those that have a particular value
for a given field. Such queries are often unsafe, and many databases do not support negation.
Nested Query
See: Query, Nested.
Normal Form
1) A condition of tables and databases intended to reduce data redundancy and improve
performance.
2) Rules and processes for putting tables and databases into normal form.
Normalization
1) The process of breaking up a table into multiple tables, each of which has a single
theme, thereby reducing data redundancy.
2) The technique that reduces or eliminates the possibility that a database is
subject to modification anomalies.
See also: Data Redundancy.
Null; Null Value
If a field contains a data item, that has a specific value. A field that does not
contain a data item is said to have a null value. In a numeric field, a null value is
not the same as a value of zero; in a character field, a null value is not the same
as a blank -- both the numeric zero and blank character are definite values. A null
value indicates that the that the field’s value is undefined -- it's value is
not known.
Topics:
Data terms: Nested Query, Normal Form, Null Value, National Change of
Address - NCOA and Negation
Download the complete Data Glossary
Topics:
Null Value, Nested Query, Normal Form, National Change of
Address - NCOA, and Negation
