多态子类错误地查询SRI子类

Question

我有一个STI子类，SoftCredits :: EventBrite＆lt; SoftCredit，具有创建SoftCredit

的函数

def create_activity
  options = {
     owner: person,
     created_at: additional_data['created_at'],
     updated_at: additional_data['updated_at'],
     trail_item_type: "Activities::EventBriteRegistration",
     trail_item_id: self.id
   }
  Activity.create(options)
end

活动模型是多态的

belongs_to :trail_item, :polymorphic => true

Activities :: EventBriteRegistration模型声明如下所示：

class Activities::EventBriteRegistration < SoftCredit
  def self.default_scope
    unscoped
  end
end

我的问题是当我有一个Activity类型的Activities :: EventBriteRegistration并且我在其上查询event_brite_registration_activity.trail_item时，查询构造如下：

SELECT "soft_credits".* FROM "soft_credits" WHERE "soft_credits"."type" IN ('Activities::EventBriteRegistration') AND "soft_credits"."id" =[id] LIMIT 1.

当然，SoftCredits没有类型的活动:: EventBriteRegistration，我很困惑如何构建它，所以当我执行event_brite_registration_activity.trail_item时，它会在SoftCredit上查询以找到正确的软信用。