A file management system removes an object from the file management system by first deleting a link to the first object. When a link to the first object is deleted the file management system determines whether there are any links to the first object remaining. If there are no links remaining, the first...http://www.google.com.au/patents/US5185885?utm_source=gb-gplus-sharePatent US5185885 - Object database deletion method for child objects when a child may be linked to multiple parent objects
