A permit-triage table includes a ticket-number column in which every value is unique, like a raw identifier. Which dataset constraint should the tester apply?

A ticket-number column where every value is unique is an identifier-like field that typically gives the model no pattern. A useful-value constraint is the check. A duplicate constraint hunts twin rows, a missing-value constraint hunts empty cells, and keeping the identifier as a feature pretends unique values are a learnable pattern.