distribute result [$$14]
-- DISTRIBUTE_RESULT  |UNPARTITIONED|
  exchange
  -- ONE_TO_ONE_EXCHANGE  |UNPARTITIONED|
    project ([$$14])
    -- STREAM_PROJECT  |UNPARTITIONED|
      assign [$$14] <- [le($$x, 2)]
      -- ASSIGN  |UNPARTITIONED|
        exchange
        -- ONE_TO_ONE_EXCHANGE  |UNPARTITIONED|
          order (ASC, $$x)
          -- STABLE_SORT [$$x(ASC)]  |UNPARTITIONED|
            exchange
            -- ONE_TO_ONE_EXCHANGE  |UNPARTITIONED|
              unnest $$x <- range(1, 4)
              -- UNNEST  |UNPARTITIONED|
                empty-tuple-source
                -- EMPTY_TUPLE_SOURCE  |UNPARTITIONED|