Uniqueness of a field

Hello!

What is the best way to keep some CDT field unique? It will be a constraint in the database, but the database error message is not user friendly.

I can set it up as a query rule or expression and validate manually in the interface. In this case the designer should remember what fields have to be validated.

May be there is an easier and straightforward way to achieve it?

OriginalPostID-273384