Question

如果我删除子记录，那么父记录不会自动删除。

class User < ActiveRecord::Base
    has_one :agency, dependent: :destroy
    accepts_nested_attributes_for :agency 
end

class Agency < ActiveRecord::Base
    belongs_to :user
    accepts_nested_attributes_for :user
end

if @agency.present?
   @agency.user.destroy
   flash[:notice] = 'Agency Deleted'                  
end

销毁子记录，以便父记录自动销毁。

Answer 1

我认为，可以像这样重写您的模型以获得预期的输出。

class User < ActiveRecord::Base
    has_one :agency # Change
    accepts_nested_attributes_for :agency 
end

class Agency < ActiveRecord::Base
    belongs_to :user, dependent: :destroy # Change
    accepts_nested_attributes_for :user
end

if @agency.present?
   @agency.destroy # Change
   flash[:notice] = 'Agency Deleted'                  
end

现在让我们进行逻辑思考。

您所做的更改是，您使User依赖于Agency，现在可以通过导轨建立父子关系以获得可接受的输出了。因此，销毁@agency时，它还将删除相关的user记录。

Answer 2

您应使用以下代码删除用户及其关联的代理商，而不对模型进行任何更改。

class User < ActiveRecord::Base
    has_one :agency, dependent: :destroy
    accepts_nested_attributes_for :agency 
end

class Agency < ActiveRecord::Base
    belongs_to :user
    accepts_nested_attributes_for :user
end

if @agency.present?
   user = @agency.user #Change
   user.destroy # This will destroy both user and associated agency.
   flash[:notice] = 'Agency and User Deleted'                  
end

可以在here.上找到有关dependent: :destroy的完整官方指南

依赖：：destroy不适用于has_one关系

2 个答案: