Tags
1NF, 2NF, 3NF, 4NF, 5NF, BCNF, DKNF, normal forms, normalization, RDBMS
1NF |
Eliminate Repeating Groups – Make a separate table for each set of related attributes, and give each table a primary key.
|
2NF |
Eliminate Redundant Data – If an attribute depends on only part of a multi-valued key, remove it to a separate table.
|
3NF |
Eliminate Columns Not Dependent On Key – If attributes do not contribute to a description of the key, remove them to a separate table.
|
BCNF |
Boyce-Codd Normal Form – If there are non-trivial dependencies between candidate key attributes, separate them out into distinct tables.
|
4NF |
Isolate Independent Multiple Relationships – No table may contain two or more 1:n or n:m relationships that are not directly related.
|
5NF |
Isolate Semantically Related Multiple Relationships – There may be practical constrains on information that justify separating logically related many-to-many relationships.
|
ONF |
Optimal Normal Form – a model limited to only simple (elemental) facts, as expressed in Object Role Model notation.
|
DKNF |
Domain-Key Normal Form – a model free from all modification anomalies. |