Question

我想在rails 3中加入更多三个表

我的代码

class offer < ActiveRecord::Base 

  belongs_to :user
  has_many :usercomments, :dependent => :destroy
  has_many :comments, :through => :usercomments, :dependent => :destroy

end

class User < ActiveRecord::Base

  has_many :usercomments, :dependent =>:destroy
  has_many :comments,:through => :usercomments, :dependent => :destroy
  has_many :offers, :dependent => :destroy

end

class Usercomment < ActiveRecord::Base

  belongs_to :user
  belongs_to :comment
  belongs_to :offer

end

class Comment < ActiveRecord::Base

  has_one :usercomment, :dependent => :destroy
  has_one :offer, :through => :usercomments
  has_one :user, :through => :usercomments

end

模式

create_table "offers", :force => true do |t|
  t.integer  "step_id"  
  t.integer  "user_id"  
  t.date     "offerdate"  
end

create_table "users", :force => true do |t|  
  t.string   "firstname",            :limit => 100, :default => ""  
  t.string   "lastname",             :limit => 100, :default => ""  
  t.string   "email",                :limit => 100  
end

create_table "usercomments", :force => true do |t|
  t.integer  "user_id"
  t.integer  "airoffer_id"
  t.integer  "comment_id"
  t.boolean  "shared"
end

create_table "comments", :force => true do |t|
  t.string   "comment" 
  t.datetime "created_at"
  t.datetime "updated_at"
end

index.html.erb

 <% airoffers.each do |airoffer| %>

???

 <% end %>

在我的html.erb页面中，我想查找商品（offer_id）和用户（user_id）的评论。

你可以帮帮我吗？谢谢，对不起我的英语表达，我是法国人。

Answer 1

这将为用户＃123和＃456

提供一系列评论

UserComment.find(:all, :conditions => {
  :user_id  => 123,
  :offer_id => 456
}).collect(&:comment)

Answer 2

在我看来，你想要的是：

class User < ActiveRecord::Base
   has_many :comments
   has_many :offers
end

class Offer < ActiveRecord::Base
   has_many :comments
   belongs_to :user
end

class Comment < ActiveRecord::Base
  belongs_to :user
  belongs_to :offer
end

如果您想要所有属于特定用户和特定优惠的评论，请执行Comment.where(:user_id => # :offer_id => #)并传入您想要的用户和优惠。

这有帮助吗？

Answer 3

最后，我选择了这个解决方案

我的代码

class offer < ActiveRecord::Base 

  belongs_to :user
  has_many :comments, :dependent => :destroy, :order => "updated_at DESC"

end

class User < ActiveRecord::Base

  has_many :comments,:dependent => :destroy
  has_many :offers, :dependent => :destroy

end

class Comment < ActiveRecord::Base

  has_one :user, :dependent => :destroy
  has_one :airoffer, :dependent => :destroy

end

模式

create_table "offers", :force => true do |t|
  t.integer  "user_id"  
  t.date     "offerdate"  
end

create_table "users", :force => true do |t|  
  t.string   "firstname",            :limit => 100, :default => ""  
  t.string   "lastname",             :limit => 100, :default => ""  
  t.string   "email",                :limit => 100  
end

create_table "comments", :force => true do |t|
  t.integer  "user_id"
  t.integer  "offer_id"  
  t.string   "comment" 
  t.datetime "created_at"
  t.datetime "updated_at"
end

在offer_controller.rb中

@offers = User.find（current_user.id）.offers.includes（：comments）

和我的index.html.erb

＆lt;％@ offers.each do | airoffer | ％GT;

＆lt;％airoffer.comments [0] .comment％＆gt;

＆lt;％end％＆gt;

我知道，这不是更好的解决方案，但是我第一次使用它。

Answer 4

我会这样用它：

Comment.find( 
  :all, 
  :conditions => {
    :user_id  => 123,
    :offer_id => 456
  },
  :join => :usercomment
)

OR：

Comment.find( 
  :all, 
  :conditions => [
    "usercomments.user_id = ? AND usercomments.offer_id = ?",
    123,
    456
  ],
  :join => :usercomment
)

Rails有很多很好的方法来编写查询。

导轨3，连接更多三个桌子

4 个答案: