,  :      ,   .
2.    -      .   - ,     ,   ,     -.
,        part_usage    :
SQL> CREATE INDEX part_usage_reverse ON part_usage
(used_in_part#, used_by_part#);
*
ERROR at line 1: ORA-25182: feature not avalable yet
,      ,       -.     ,        -,     .      .
:
  ,     -,             .      ,   ,  ,       .  ,       ,       .
   
  ,     (reversed key index)    . , , -        ?      ,   ,      .           ,   ,       .
   ,    ,     (  ,     )        ,          .              - ,          .    ,    -
4.  ""  Oracle8	69