Recognises a physical domain differing from the logical domain
A datatype, length, scale, character set or nullability that admits values the logical domain forbids, or cuts off values it allows. Includes a foreign key typed differently from the key it references.
Can AI do this?
AI does this partly Some of the tested AI models master this; others do not show it. 4 of 10 models master it.
| Model | Tier | Probability of mastery | Status |
|---|---|---|---|
| gemini-4-argon | Flagship | 99% | Mastered |
| gemini-3.1-pro-preview | Flagship | 72% | Not shown |
| gpt-6-astra | Flagship | 100% | Mastered |
| claude-fable-5-1 | Flagship | 100% | Mastered |
| gemini-3.8-flash | Mid tier | 70% | Not shown |
| gpt-6.1-sol | Mid tier | 93% | Not shown |
| claude-sonnet-5-5 | Mid tier | 100% | Mastered |
| gemini-3.5-flash-lite | Low cost | 72% | Not shown |
| gpt-6-luna | Low cost | 94% | Not shown |
| claude-haiku-5-5 | Low cost | 70% | Not shown |
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 column and the values it wrongly admits or cuts off
How it is assessed: Flags the deficient case and passes the acceptable one. Deficient: account_currency_code VARCHAR(50): 'EUR', 'eur' and 'EUR ' all load. account_identifier VARCHAR(10) for a logical length of 20. payment.account_id INTEGER referencing BIGINT. A date as VARCHAR. A name column in a character set that cannot hold õ, ä, ö, ü, š, ž Acceptable: CHAR(3) with an uppercase-letters check; lengths at least the logical ones; foreign-key types identical to the referenced key; DATE; a Unicode character set (PHY-008, PHY-023)
Also known as: Physical domain differs from the logical domain (physical model)
Related knobits
Builds on
Needed for
- K-816 Recognises one decimal scale for every currency
- K-817 Recognises a length taken from sample data
- K-827 Recognises an event timestamp stored without a time zone
- K-828 Recognises a business date stored with a time of day
All 40 knobits of Design the physical data model.
Source: Review checklist 06-physical, row 17; Codd 1970; S&W 11.4; E&N 17.7