A method and apparatus for implementing directory services, such as X.500 and LDAP in a SQL environment, and for providing a desired level of indexing, extensibility and scalability. In the directory service system, a plurality of objects are defined to be hierarchical, and the relationships among objects...http://www.google.de/patents/US20030105749?utm_source=gb-gplus-sharePatent US20030105749 - Metadata in directory service systems and methods
