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The Unresolvable Subject Deletion Utility (USDU) finds and optionally deletes memberships for subjects which can not be found by their source.
An unresolvable subject is a subject that can not be found by its source. A subject may be unresolvable because of a temporary or permanent source failure, or because it was removed from its source before memberships or privileges were deleted or revoked.This utility attempts to lookup every member's subject. If a subject can not be found, it's immediate memberships are printed and optionally deleted.
A future version may extend the Source class to provide more efficient lookups of subjects.
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