Question

我发货有一张发票;发票属于发货。货运表是包含customer_id的货运单。

我需要找到所有发票......

针对特定客户
，其customer_account_balance为0

我尝试了很多不同的方法，但似乎都没有用，最后一个让我错误private method select或类似的东西......

reports_controller.rb
i = Invoice.where("customer_open_balance != 0")
s = Shipment.find_by_customer_id(@customer.id)
shipment_ids_from_invoices = i.map{|x| x.shipment_id}
@shipments = s.select{|z| shipment_ids_from_invoices.include? z.id}

Answer 1

这有用吗？

@shipments = Shipment.joins(:invoice).where(:customer_id => @customer.id).where("customer_account_balance <> 0")

听起来你的架构看起来像这样：

Shipment: (customer_id, ...)
Invoice: (customer_open_balance, shipment_id, ...)

您是否将has_one :invoice放入Shipment.rb并将belongs_to :shipment放入Invoice.rb？

Answer 2

class Invoice

  belongs_to :shipment

  scope :with_customer, lambda { |customer_id| joins(:shipment).where(:customer_id => customer_id) }

  scope :cero_balance, joins(:shipment).joins(:customer).where("customer_account_balance <> 0")

end

然后尝试

#for a particular customer with id 1
Invoice.with_customer 1

#that have customer_account_balance of 0
Invoice.cero_balance

Rails 3.如何进行嵌套属性查询？

2 个答案: