ALTER INDEX [ schema. ]index
  { { {deallocate_unused_clause | allocate_extent_clause}
    | parallel_clause
    | physical_attributes_clause
    | logging_clause
    }
      [ { deallocate_unused_clause | allocate_extent_clause }
        | parallel_clause
        | physical_attributes_clause
        | logging_clause
      ]...
  | rebuild_clause
  | PARAMETERS ('ODCI_parameters')
  | { ENABLE | DISABLE }
  | UNUSABLE
  | RENAME TO new_name
  | COALESCE
  | { MONITORING | NOMONITORING } USAGE
  | UPDATE BLOCK REFERENCES
  | alter_index_partitioning
  } ;