ALTER INDEX <index-name> -------+
  +-------------------------------+
  +---+-> add-partition-clause -------------------------------------+->
      +-> BUILD PARTITION <partition-name> -------------------------+
      +-> BUILD ALL PARTITIONS -------------------------------------+
      +-> DROP PARTITION <partition-name> --------------------------+
      +-> MOVE PARTITION <partition-name> TO area-spec   -----------+
      +-> REBUILD PARTITION <partition-name> -----------------------+
      +-> REBUILD ALL PARTITIONS -----------------------------------+
      +-> RENAME PARTITION <partition-name> TO <new-partition-name> +
      +-> TRUNCATE PARTITION <partition-name> ----------------------+
      +-> TRUNCATE ALL PARTITIONS ----------------------------------+
      +-> alter-index-attributes -+------------------------+--------+
                                  +-> index-store-clause --+

  add-partition-clause =

  -> ADD PARTITION <partition-name> ---+
  +------------------------------------+
  +-> USING -> ( -+-> <column-name> -+-> ) -+
                  +------- , <-------+      |
  +-----------------------------------------+
  +-> IN area-spec -------------------------+
  +-----------------------------------------+
  +--+----------------------------------------------+->
     +-> WITH LIMIT OF -> ( -+-> <literal> -+-> ) --+
                             +------ , <----+

  area-spec =

  --> <area-name> -+---------------------------------------------------+->
                   +-> ( -++-> threshold-clause ---------------++-> ) -+
                          |+-> LOGGING ------------------------+|
                          |+-> NOLOGGING ----------------------+|
                          |+-> PARTITION <name> ---------------+|
                          |+-> COMMENT IS -+--> 'string' ---+--+|
                          |                +------- / <-----+   |
                          +---------------- ,  -----------------+

  alter-index-attributes=

  -+-+---------------------------------------------------------+-+->
   | +-> threshold-clause -------------------------------------+ |
   | +-> DUPLICATES ARE ALLOWED -------------------------------+ |
   | +-> LOGGING ----------------------------------------------+ |
   | +-> NOLOGGING --------------------------------------------+ |
   | +-> NODE SIZE <number-bytes> -----------------------------+ |
   | +-> PERCENT FILL <percentage> ----------------------------+ |
   | +-> PREFIX CARDINALITY COLLECTION IS -+-> ENABLED ------+-+ |
   | |                                     +-> ENABLED FULL -+ | |
   | |                                     +-> DISABLED -----+ | |
   | +-> USAGE -+-> UPDATE -+----------------------------------+ |
   | |          +-> QUERY --+                                  | |
   | +-> COMMENT IS -+-> '<string>' --+------------------------+ |
   | |               +----- / --------+                        | |
   | +-> MAINTENANCE IS -+-> DISABLED -----------------+-------+ |
   |                     +-> ENABLED -+--------------+-+         |
   |                                  +-> DEFERRED --+           |
   |                                  +-> IMMEDIATE -+           |
   +---------------------------- <-------------------------------+

  threshold-clause =

  --+-> THRESHOLD -+-> IS -+-> ( --> <val1> --> ) ---------+->
    |              +-> OF -+                               |
    |                                                      |
    +-> THRESHOLDS -+-> ARE -+-----------+                 |
                    +-> OF  -+           |                 |
      +----------------------------------+                 |
      +-> ( --> <val1> -+---------------------------+-> ) -+
                        +-> , <val2> -+-------------+
                                      +-> , <val3> -+

  index-store-clause =

  STORE ----------------------+
  +---------------------------+
  ++-> IN area-spec ---------------------------------------------+>
   +-> USING -> ( -+--> <column-name> -+-> ) ----------+         |
                   +------- , <--------+               |         |
   +---------------------------------------------------+         |
   ++> IN area-spec -------------------------------------+       |
    | +--------------------------------------------------+       |
    | +-> WITH LIMIT OF -> ( -+--> <literal> -+-> ) ---+---+     |
    |                         +------ , <-----+        |   |     |
    +-----------------------<--------------------------+   |     |
  +--------------------------------------------------------+     |
  ++------------------------------------------------------------++
   +-> OTHERWISE IN area-spec ----------------------------------+