Question

在将两个模型连接到n..n关联时遇到问题。

我在上下文中具有以下关联：

提案n..n产品
提案n..n项目
提案n..n NewProject

与此类似，我有：

订购n..n产品
订购n..n项目
订购n..n NewProject

嗯，联接模型在两种情况下都具有相同的属性，但每种情况下的部分属性都不同。

是否有一种方法可以创建单个联接模型（Item），该模型可以存储所有数据，并且可以与Order和Proposal中的三个不同别名一起使用？

我试图这样编码，但是没有用。.

proposal.rb

    class Proposal < ActiveRecord::Base
      ...
      has_many :items
      has_many :products, through: :items, source: :requisition, source_type: "Produto"
      has_many :projects, through: :items, source: :requisition, source_type: "Projeto"
      has_many :projects, through: :items, source: :requisition, source_type: "Novo"
      ...
    end

order.rb

    class Order < ActiveRecord::Base
      ...
      has_many :items, as: :requisition, dependent: :destroy
      has_many :products, through: :items, source: :requisition, source_type: "Produtos"
      has_many :projects, through: :items, source: :requisition, source_type: "Projetos"
      has_many :projects, through: :items, source: :requisition, source_type: "Novos"
      ...
    end

product.rb

    class Product < ActiveRecord::Base
      has_many :items, as: :piece, dependent: :destroy
      has_many :orders, through: :items, source: :piece, source_type: 'Order'
      has_many :proposals, through: :items, source: :piece, source_type: 'Proposal'
      ...
    end

project.rb

    class Project < ActiveRecord::Base
      has_many :items, as: :piece, dependent: :destroy
      has_many :orders, through: :items, source: :piece, source_type: 'Order'
      has_many :proposals, through: :items, source: :piece, source_type: 'Proposal'
      ...
    end

item.rb

    class Item < ApplicationRecord
      belongs_to :piece, polymorphic: true
      belongs_to :requisition, polymorphic: true
      ...
    end

我希望统一这种关联，清除一些表，并尝试加快应用程序的速度。

has_many通过多态，两侧都有别名

0 个答案: