highcharts with datetime

user_totals.html.haml

#user_totals_chart

:javascript
  Chart = {}
  Chart.series = [{
    data: #{User.order("created_at").group("date(created_at)").select("count(id) as total, date(created_at) as created_at").all.map {|u| [u.created_at.to_i * 1000, u.total.to_i]}},
    name: 'Benutzer'
  }];

:coffeescript
  new Highcharts.Chart
    chart: 
      renderTo: 'user_totals_chart'
      zoomType: 'x'
    title: { text: 'Benutzer/Tag'}
    xAxis: { type: 'datetime' }
    yAxis:
      title: { text: 'Anzahl' }
    series: Chart.series