Question

我有一张表，记录员工一个月内收到的票数

[<Placement id: 1, employee_id: 1, month: "2014-02-01", votes: 2>, 
<Placement id: 2, employee_id: 1, month: "2014-01-01", votes: 2>, 
<Placement id: 3, employee_id: 2, month: "2014-02-01", votes: 1>,
<Placement id: 4, employee_id: 2, month: "2014-01-01", votes: 3>
<Placement id: 5, employee_id: 3, month: "2014-02-01", votes: 9>]

我现在想要跟踪他们在每个月末的位置（大多数选票在第1位等）。

我要将列：位置添加到Placements模型中，如下所示：

[<Placement id: 1, employee_id: 1, month: "2014-02-01", votes: 2, position: 2>, 
<Placement id: 2, employee_id: 1, month: "2014-01-01", votes: 2, position: 2>, 
<Placement id: 3, employee_id: 2, month: "2014-02-01", votes: 1, position: 3>,
<Placement id: 4, employee_id: 2, month: "2014-01-01", votes: 3, position: 1>
<Placement id: 5, employee_id: 3, month: "2014-02-01", votes: 9, position: 1>]

我在heroku调度程序中有这样的东西：

if Date.today == Date.today.end_of_month
 Placement.each_with_index do |p, index|
  p.update_attributes(position: index+1)
 end
end

我如何比较所有相同月份的投票？这比较了所有月份

Answer 1

要在一个月内运行并更新位置，您可以：

def update_single_month(month)
  Placement.where(month: month).order('votes desc').each_with_index do |placement, position|
    placement.position = position
    placement.save!
  end
end

要运行所有现有数据，您只需知道您已拥有数据的月份：

def update_all_months
  Placement.select(:month).group(:month).each { |r| update_single_month(r.month) }
end

如何计算每个月末的排行榜

1 个答案: