Explains candidate key and prime attribute
A candidate key is a minimal set of attributes that determines all others; a prime attribute belongs to a candidate key.
Can AI do this?
AI does this well Most of the tested AI models master this. 10 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% | Mastered |
| 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: A candidate key is a minimal set of attributes that determines all others; a prime attribute belongs to a candidate key
How it is assessed: Finds every candidate key of a sample entity from its dependencies and classifies its attributes as prime or non-prime
Related knobits
Builds on
Needed for
- K-311 Recognises a uniqueness rule with no unique key behind it
- K-532 Records the functional dependencies of an entity
- K-555 Explains second normal form
- K-556 Explains third normal form
- K-561 Explains domain-key normal form
- K-563 Explains lossless-join decomposition
- K-568 Explains natural keys, surrogate keys and key stability
- K-904 Explains identifying and non-identifying relationships
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