Execution example::

  select NearTokens --match_columns content --query '*NP1"groonga pgroonga"'
  # [
  #   [
  #     0,
  #     1337566253.89858,
  #     0.000355720520019531
  #   ],
  #   [
  #     [
  #       [
  #         1
  #       ],
  #       [
  #         [
  #           "_id",
  #           "UInt32"
  #         ],
  #         [
  #           "content",
  #           "ShortText"
  #         ]
  #       ],
  #       [
  #         7,
  #         "groonga rroonga pgroonga mroonga"
  #       ]
  #     ]
  #   ]
  # ]
