The SORT statement orders a table.  It sorts the table elements
  based on the keys as specified in the OCCURS for the table.  The
  table keys as specified in the OCCURS can be overridden with keys
  as specified in the SORT statement.  If no key is specified, the
  table elements are the SORT keys.

  Format -

   SORT table-name [ ON { ASCENDING  } KEY { sortkey } ... ] ...
                   [    { DESCENDING }                     ]

      [ WITH DUPLICATES IN ORDER ]

      [ COLLATING SEQUENCE IS alpha ].