title: Multiple foreign key referencing same attribute
body: <p>If a table has multiple foreign keys which reference same attribute of another table, how should be it written?</p>
  
  <p><strong>foreign key(A,B) references table_name(C)</strong></p>
  
  <p>or,</p>
  
  <p><strong>foreign key(A,B) references table_name(C,C)</strong></p>
  
  <p>here, A,B,C are attributes.</p>