Data Analysis for Database Design
Normalization Example
- Third Normal Form:
- Third normal form analysis looks for two types of problems, derived data and transitive dependencies. (continued)
- A transitive dependency exists when a non-key attribute is dependent on another non-key attribute (other than by derivation).
- This error usually indicates that an undiscovered entity is still embedded within the problem entity.
- Transitive analysis is only performed on those entities that do not have a concatenated key.
- “An entity is said to be in third normal form if every non-primary key attribute is dependent on the primary key, the whole primary key, and nothing but the primary key.”