Question

只是在玩RoR，尝试通过一些建模找到方法。请注意以下代码：

 class Picture < ActiveRecord::Base
      belongs_to :imageable, :polymorphic => true
 end

 class Employee < ActiveRecord::Base
      has_many :pictures, :as => :imageable
 end

 class Product < ActiveRecord::Base
      has_many :pictures, :as => :imageable
 end

有没有办法按照特定图片获取产品？ 我正在尝试这个，但它不起作用：

picure = Picture.last
product = Product.where(picture: picure)

失败了：

SQLite3::SQLException: no such column: products.picture: SELECT "products".*
FROM "products" WHERE "products"."picture" IS NULL LIMIT 1```

Answer 1

如果您有Picture @picture的实例，则可以使用belongs_to将其与Product相关联（假设Picture实际上是Product属于Employee而非product = @picture.imageable）

的实例

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通过多态关联查询

1 个答案: