# File SQLRelay.rb, line 119
  def rollback
    $stderr.puts "Warning: Rollback ineffective while AutoCommit is on" if @attr['AutoCommit']

    case @handle.rollback
    when 0
      # failed
      raise DBI::OperationalError.new("Rollback failed")
    when -1
      raise DBI::OperationalError.new("Error occured during rollback")
    end
  end