graph = DashingGraph.new 'Users' => '#ff0000',
                         'Orders' => '#00ff00'
db[:users]
  .select(:created_at)
  .each do |row|
    # Group by day
    time = Time.at(row[:created_at]).to_datetime.at_beginning_of_day.to_i,
    # Add to the graph
    graph.add_point 'Users', time, 1
  end
db[:orders]
  .select(:created_at)
  .each do |row|
    # Group by day
    time = Time.at(row[:created_at]).to_datetime.at_beginning_of_day.to_i,
    # Add to the graph
    graph.add_point 'Orders', time, 1
  end
send_event('users-and-orders-per-day', graph)