在活动记录中乘列？

Question

具有以下sql查询，如何转换Active Record中两列的乘法？

SELECT plan_name, plan_price, count(plan_id), plan_price*count(plan_id) AS totalrevenue
FROM leads
INNER JOIN plans p ON leads.plan_id = p.id
WHERE lead_status_id = 5
GROUP BY plan_name, plan_price;

Answer 1

我会尝试这样的事情。

leads = Lead.joins(:plans).
    where(lead_status_id: 5).
    group(:plan_name, :plan_price).
    select('plan_name, plan_price, count(plan_id), plan_price * count(plan_id) AS totalrevenue')

leads.each { |lead| puts lead.totalrevenue }

注意：

1. 我不知道它是joins(:plan)还是joins(:plans)，这取决于您的关联
2. 如果您甚至需要打电话给plan_id，我都会在该字段中甚至给一个名字
3. 如果打印整个对象，则不会替换totalrevenue之类的字段，因为它不是对象的一部分，而是虚拟属性