This sentence can be derived by concatenating the text values and placeholders associated with each role. Attribute The attribute or set of attributes that is used to uniquely identify an instance of an entity type. May be derived from associations or the object type's heritage. Attribute The attribute that holds the value assigned to an instance of a value type. The ORM language is rich with constraint types.
Constraints consistently inolve interactions among roles.
This contrasts with standard UML, which focuses on constraints for classes, associations and attributes. Constraint A general constraint exhibiting properties common to all ORM constraint types. This sterotype may be used to document constraints that do not conform to the pre-defined constraint stereotypes. Other ORM constraint stereotypes inherit from ormConstraint. Constraint Constrains a set of roles in such a way that each instance of the set of constrained roles is distinguishable from every other instance.