# File lib/sdb/right_sdb_interface.rb, line 570
    def select(select_expression, next_token = nil)
      select_expression      = query_expression_from_array(select_expression) if select_expression.is_a?(Array)
      @last_query_expression = select_expression
      #
      request_params = { 'SelectExpression' => select_expression,
                         'NextToken'        => next_token }
      link   = generate_request("Select", request_params)
      result = select_response_to_ruby(request_info( link, QSdbSelectParser.new ))
      return result unless block_given?
      # loop if block if given
      begin
        # the block must return true if it wanna continue
        break unless yield(result) && result[:next_token]
        # make new request
        request_params['NextToken'] = result[:next_token]
        link   = generate_request("Select", request_params)
        result = select_response_to_ruby(request_info( link, QSdbSelectParser.new ))
      end while true
    rescue Exception
      on_exception
    end