This example was either so simple that it was instantly determined or it made not sense at all.
Keys exist over A , B , and C .
An employee number identifies a person. A passport number identifies a person. Dr. John Sharp is the founder and principal consultant for Sharp Informatics. Before starting Sharp Informatics in 1997 he was employed by Sandia National Laboratories in Albuquerque, NM for 18 years. While at Sandia he held staff and management positions in all areas of information technology, including analysis, design, implementation, maintenance, information architecture, data administration, and information technology research.