Compare the rule with concrete cases
Original fictional model: an asset may have zero or many observation records; each observation belongs to exactly one asset. An asset without observations is permitted. An observation linked to two assets is not.
| Case | Asset observations | Assets per observation | Result |
|---|---|---|---|
| K1 | 0 | No observation exists | Valid asset |
| K2 | 3 | 1 each | Valid relationship |
| K3 | 1 shared observation | 2 | Invalid observation link |
Work through the distinction
“One-to-many” shorthand leaves minimums unclear. Write both directions with zero, one or many so an empty but legitimate asset is not removed to satisfy an invented minimum.
Can an observation with no asset be saved under this model?
Show the worked answer
No. The observation side requires exactly one, so zero is invalid even though an asset may have zero observations.
Acceptance wording to adapt
Allow zero or more observations per asset. Require exactly one existing asset reference per observation. Reject missing or multiple asset links on an observation.