Occasionally, it may be necessary to include more than one entity of the same name in a Vocabulary. This can be accomplished using Domains (similar to Java packages and XML namespaces.) Domains allow us to bundle one or more entities in a subset within the Vocabulary, allowing us to reuse entity names so long as the entity names are unique within each Domain. Additional Domains, referred to as sub-Domains, can be defined within other Domains.
Select Vocabulary > Add Domain from the Studio menubar or click from the Studio toolbar.
A new folder is listed in the Vocabulary tree. Assign it a name. The example in the following figure shows a Vocabulary with two Domains, US_Fleet and WW_Fleet:
Figure 26. Using domains in the Vocabulary>
Notice that the entity Aircraft appears in each Domain, using the same spelling and containing slightly different attributes ( FAAnumber vs. ICAOnumber ). Notice too that the association role names from FlightPlan to Aircraft have been named manually to ensure uniqueness: one is now USaircraft and the other is WWaircraft.
from the Studio toolbar.
is listed in the Vocabulary tree. Assign it a name. The example in the following figure shows a Vocabulary with two Domains, US_Fleet and WW_Fleet:
