Description of the illustration last.eps

aggregate_function KEEP
  (DENSE_RANK LAST ORDER BY
    expr [ DESC | ASC ]
         [ NULLS { FIRST | LAST } ]
    [, expr [ DESC | ASC ]
            [ NULLS { FIRST | LAST } ]
    ]...
  )
  [ OVER { window_name |  [ window_name ] query_partition_clause  }
  ]