Question

我的模特：

OrderStatus 
  belongs_to Order

Order
  has_one OrderStatus
  belongs_to Logo

Logo
  has_many Orders

我想对名为artwork的Logo模型属性执行查询：

OrderStatus.includes({:order => :logo}).where(:order => {:logo => {:artwork => search_artwork}})

但它基本上会抛出一个错误：

SQLite3::SQLException: no such column: order.logo: SELECT COUNT(DISTINCT "order_statuses"."id") FROM "order_statuses" LEFT OUTER JOIN "orders" ON "orders"."id" = "order_statuses"."order_id" LEFT OUTER JOIN "logos" ON "logos"."id" = "orders"."logo_id" WHERE "order"."logo" = '--- :artwork: xxxxxxx'

我看不出这个错误的原因。

修改

经过广泛搜索后，我意识到部分应该使用表名（即复数），所以我的代码应该是

@order_statuses = OrderStatus.includes(:order => [:logo]).where(:orders => {:logos => {:artwork => search_artwork}})

但我仍然看到SQLite3异常错误

SQLite3::SQLException: no such column: orders.logos: SELECT COUNT(DISTINCT "order_statuses"."id") FROM "order_statuses" LEFT OUTER JOIN "orders" ON "orders"."id" = "order_statuses"."order_id" LEFT OUTER JOIN "logos" ON "logos"."id" = "orders"."logo_id" WHERE "orders"."logos" = '--- :artwork: xxxxxxxx '

Answer 1

快速回答

我仍然看到SQLite3异常错误... temp16＆＃34;

您的inFile.read(reinterpret_cast<char*>(&temp16), 2);表格是否没有名为no such column: orders.logos的列，它有一个名为orders的列，该列是在您在评论中提到的迁移中创建的。

发生此错误的原因是Rails并不理解（据我所知）logos子句中的嵌套值。

也许更重要的是，我认为您（可能）更感兴趣的是：

如何编写逻辑，为logo_id提供与.where相关的所有OrderStatus条Logo值等于artwork？

如果是这样，为search_artwork模型添加has_one :through关系会让这很容易！

Logo

然后，您的查询应该如下：

~~Logo.where（artwork：search_artwork）.includes（：orderStatus）~~

编辑：oops以上是错误的

OrderStatus 
  belongs_to Order

Order
  has_one OrderStatus
  belongs_to Logo

Logo
  has_many Orders
  has_many OrderStatuses, :through => :Order # This is what you're adding!

有关Rails关系和使用Logo.where(artwork: search_artwork).order_statuses的更多信息，请参阅： http://guides.rubyonrails.org/association_basics.html#the-has-many-through-association

查询嵌套模型属性时出错

1 个答案: