Recognises an entity identified only by a system-assigned key
The entity's only identifier is a number the system assigns, and nothing the business uses to tell instances apart is recorded as natural_key. Nothing then stops the same thing being recorded twice. A surrogate key is a physical decision in this skill. A specific form of row 17.
Can AI do this?
AI does this partly Some of the tested AI models master this; others do not show it. 6 of 10 models master it.
| Model | Tier | Probability of mastery | Status |
|---|---|---|---|
| gemini-4-argon | Flagship | 100% | Mastered |
| gemini-3.1-pro-preview | Flagship | 91% | Not shown |
| 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 | 49% | Not shown |
| claude-sonnet-5-5 | Mid tier | 100% | Mastered |
| gemini-3.5-flash-lite | Low cost | 60% | Not shown |
| gpt-6-luna | Low cost | 55% | Not shown |
| 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: The entity and the business identifier it lacks as a natural key
How it is assessed: Flags the deficient case and passes the acceptable one. Deficient: Party with primary_key: [Party Id] and no natural_key; the same company registered twice under two ids Acceptable: primary_key and natural_key on the business identifier (registry code, personal identification code); where none exists, say so and record the duplicate-matching rule as a data rule with an enforcement
Also known as: System-assigned key only (logical model)
Related knobits
Builds on
Needed for
All 56 knobits of Derive the logical data model.
Source: Review checklist 05-logical, row 18; Karwin, ID Required; S&W ch. 6