Here DealerID can be nullable and CarID, TyreID are unqiue.
The problem I have noticed is: Grails ignores nulls in unique constraints.
+1
A:
I don't think the question is clear, but this may be a bug in Grails: http://jira.codehaus.org/browse/GRAILS-5101
Alison
2010-04-13 12:56:53
This is a bug. A major one if you ask me. It was a regression from v1.1 to v1.2.
Tiggerizzy
2010-04-13 15:14:14
Presumably you could implement the restrictions you want using custom constraints (see e.g. http://stackoverflow.com/questions/2590906/testing-custom-constraints-in-grails-app).
Alison
2010-04-15 11:14:46