select (select table_name || '.' || column_name from user_cons_columns where constraint_name = uc.constraint_name) 
              || ' references ' ||
             (select table_name || '.' || column_name from user_cons_columns where constraint_name = uc.r_constraint_name) as references
        from user_constraints uc 
       where constraint_type = 'R' 
        and table_name = upper('&table_name')

select (select table_name || '.' || column_name from user_cons_columns where constraint_name = uc.r_constraint_name) 
              || ' is referenced by ' ||
             (select table_name || '.' || column_name from user_cons_columns where constraint_name = uc.constraint_name) as referenced_by
        from user_constraints uc 
       where constraint_type = 'R' 
        and r_constraint_name in (select constraint_name from user_constraints where table_name = upper('&table_name'))