Normalization
The process of modeling data into relational tables is knownw as normalization.
| Normalization | Normal Form | Characterstics | Dependency |
|---|---|---|
| First Normal Form (1NF) | No repeating groups, all tables are two-dimensional. | F D U E N P C E T N I D O E N N A C L Y |
| Second Normal Form (2NF) | !NF plus each data element is identified by one corresponding unique identifier a primary key that is not a composite and therefore connot be subdivided int smaller bits of data. | |
| Third Normal Form (3NF) | 2NF plus all tables contain no data other than that which describes the intent of a primary key extraneous data is placed in separate tables. | |
| Boyce-Codd Normal Form (BCNF) | A modified version of 3NF designed to eliminate structures that might allow some rare logical inconsistencies to appear in the data. | |
| Fourth Normal Form (4NF) | BCNF plus additional logic to ensure that evert multivalued dependency is dependent on a superkey. | Multivalued Dependency |
| Fifth Normal Form (5NF) | 4NF plus evert join dependency for the table is a result of the candidate keys. | Join Dependency |
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