Why is Domain required for an identity in the FIM Service?

Question

I have a scenario where FIM is managing identity, but not all identities have an Active Directory account. I have a flag in the FIM Portal (Service) that indicates if a particular
user is entitled to an AD account or not. My provisioning setup adds or removes the AD account as appropriate. To support FIM Portal activities for those that do have AD accounts, I populate AccountName, Domain, and ObjectSID in the FIM Service from their
corresponding attributes in AD.
What I have noticed is that it does not seem possible to null out or delete the Domain attribute for a user in the FIM Service. I can delete the attributes for both AccountName
and ObjectSID without issues.
When attempting to remove the Domain attribute for a user I get the following in the event logs:
Microsoft.ResourceManagement.WebServices.Exceptions.UnwillingToPerformException: Other ---> System.Data.SqlClient.SqlException: Procedure or function 'GetDomainConfigurationIdentifiersFromDomain'
expects parameter '@domainName', which was not supplied.
I assume that something internal to the FIM Service is trying to do some magic with validating the domain name and the domain configuration. I did found a post saying, “Yeah,
you have to populate Domain”:
http://social.technet.microsoft.com/Forums/en-US/f207caa9-3a6f-4f2d-8461-a83777280803/fim-service-ma-export-failedmodificationviawebservices-error?forum=ilm2
My question is why is Domain required for a user? It is obviously needed for users that have AD accounts an must authenticate with the Portal, but in the case where a user
does not have an account (and therefore does not have a domain), it feels odd to store the incorrect data for the user. It also looks weird when you bring up list of users in the portal and see domain values for users that do not have accounts. In this particular
case, the client has many domains and does have the Domain and AccountName attributes displayed on the user search results page.

Answer 1

Hi Henry,
Using another domain attribute and workflow to maintain the actual Domain and DomainConfiguration is a good suggestion, thanks.
My original question still stands however... Why is Domain required in the FIM Service?
It is sounding like the answer is "It is not really required on it's own, but there is an internal process that requires it if there is a value for DomainContext set (and there is some magic that sets DomainContext, so you have to manually clear it.)"
Since DomainContext is automatically set when a client writes a value to Domain. I would suggest that it is a bug that DomainContext is not automatically cleared when Domain is cleared.
I poked around a bit and the bug can be fixed by changing the stored procedure definition to allow null parameters. In the FIM Service database the stored procedure [fim].[GetDomainConfigurationIdentifiersFromDomain] has a parameter declaration of "@domainName
NVARCHAR(448)". If this is changed to "@domainName NVARCHAR(448) = null" the problem appears to be solved.
Making this change would of course be totally unsupported, but perhaps it can be included in a future product update.
For now I will use Henry's workaround, or just live with potential out of date Domain data.
 Thanks