Stage 5: Derive the logical data model
Knobit of Data modelling · K-559 · Knowledge
Explains join dependency and fifth normal form
What it means
When a three-way entity is the join of its projections, and the cyclic rule that makes it so.
How it is assessed
Decides for sample three-way entities whether a cyclic rule holds and whether the entity should be decomposed
Builds on
- Explains multivalued dependency and fourth normal formK-558 · Knowledge
Needed by
- Recognises a join dependency kept in one entityK-513 · Skill
- Recognises a connection trapK-523 · Skill
- Explains sixth normal form for temporal dataK-560 · Knowledge