如何通过has_many关联循环访问 ActiveRecord 关系-解网

问：

所以我有某些冰淇淋，我想在其中获得安大略省低脂冰淇淋和未过期冰淇淋的销售额。

冰淇淋has_many ontario_sales_receipts：

included_ice_cream = IceCream.produced_this_or_previous_month.where(low_fat: true, expired: false)

final_amount = included_ice_cream.ontario_sales_receipts.pluck(:number_of_buckets).sum * BUCKET_PRICE

但这导致：

undefined method `ontario_sales_receipts' for #<IceCream::ActiveRecord_Relation:0x0055de80e3ffa8>

如何使 ActiveRecord 关系中的has_many关联可用？

我最初可以查询 OntarioSaleRecept，但我不知道如何根据它们与特定冰淇淋的has_one关联来查询它们

included_ontario_sales_receipts = OntarioSalesReceipt.where( their associated IceCream is lowfat and non expired ... )

Ruby-on-Rails 关联 rails-activerecord

included_ice_cream = IceCream.produced_this_or_previous_month.where(
      low_fat: true,
      expired: false
    )
    total_amount = final_amount(included_ice_cream)

    def final_amount(included_ice_cream)
      included_ice_cream.map do |ice_cream|
        ice_cream.ontario_sales_receipts.pluck(:number_of_buckets).sum *
          BUCKET_PRICE
      end.sum
    end

这个怎么样？

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如何通过has_many关联循环访问 ActiveRecord 关系

How to iterate over ActiveRecord relation through a has_many association

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