Execution example::

  select --table Comments --query comment:@Now --output_columns comment,_score
  # [
  #   [
  #     0, 
  #     1337566253.89858, 
  #     0.000355720520019531
  #   ], 
  #   [
  #     [
  #       [
  #         2
  #       ], 
  #       [
  #         [
  #           "comment", 
  #           "ShortText"
  #         ], 
  #         [
  #           "_score", 
  #           "Int32"
  #         ]
  #       ], 
  #       [
  #         "I've just used 'Try-Groonga' now! #groonga", 
  #         1
  #       ], 
  #       [
  #         "I'm at the Museum of Modern Art in NY now!", 
  #         1
  #       ]
  #     ]
  #   ]
  # ]
