Explains relationship cardinality and optionality
Minimum and maximum participation of each end of a relationship, read in both directions.
Can AI do this?
AI does this well Most of the tested AI models master this. 9 of 10 models master it.
| Model | Tier | Probability of mastery | Status |
|---|---|---|---|
| gemini-4-argon | Flagship | 100% | Mastered |
| gemini-3.1-pro-preview | Flagship | 100% | Mastered |
| gpt-6-astra | Flagship | 100% | Mastered |
| claude-fable-5-1 | Flagship | 100% | Mastered |
| gemini-3.8-flash | Mid tier | 100% | Mastered |
| gpt-6.1-sol | Mid tier | 100% | Mastered |
| claude-sonnet-5-5 | Mid tier | 100% | Mastered |
| gemini-3.5-flash-lite | Low cost | 100% | Not shown |
| gpt-6-luna | Low cost | 100% | Mastered |
| claude-haiku-5-5 | Low cost | 100% | Mastered |
Mastered means a probability of at least 90% that the model has this knobit, estimated from its graded answers. “Not shown” means the answers do not settle it either way. How the models are tested.
What it looks like in practice
Expected result: Minimum and maximum participation of each end of a relationship, read in both directions
How it is assessed: States the cardinality and optionality of sample relationships in both directions from their rules
Related knobits
Needed for
- K-112 Recognises a mandatory attribute without its moment of obligation
- K-318 Recognises a cardinality rule stated from one end only
- K-521 Recognises an unresolved many-to-many relationship
- K-522 Recognises a polymorphic association
- K-526 Recognises a redundant relationship
- K-529 Recognises a relationship contradicting its data rule
- K-534 Resolves a many-to-many relationship into an associative entity
- K-569 Explains the connection, fan and chasm traps
- K-653 Explains referential integrity and referential actions
- K-711 Recognises a check weaker than its rule
All 56 knobits of Derive the logical data model.
Source: Normalisation theory and relational design (Codd, Fagin, Date), as used by the stage 5 reference and review checklist