我有2個模型：Doc和Row。 Doc有許多行和一行belongs_to單個文檔。Rails 4 - 兩個模型設置爲一對多關聯，但不能拉出與一個模型相關的所有記錄

這裏是模型看起來像在代碼：

Doc: 
# == Schema Information 
# 
# Table name: docs 
# 
# id   :integer   not null, primary key 
# created_at :datetime 
# updated_at :datetime 
# numrows :integer 
# user  :string(255) 
# source  :string(255) 
# size  :string(255) 
# location :string(255) 
# status  :string(255) 
# 

class Doc < ActiveRecord::Base 
    has_many :rows

行：

# == Schema Information 
# 
# Table name: rows 
# 
# id   :integer   not null, primary key 
# created_at :datetime 
# updated_at :datetime 
# numCols :integer 
# type  :string(255) 
# content :text 
# status  :string(255) 
# doc_id  :integer 
# 

class Row < ActiveRecord::Base 
    belongs_to :doc, :foreign_key => "doc_id", :class_name => "Doc" 

=begin 
Status of a row can be: 
1) header 
2) body 
3) ignore 
4) nil 
=end

現在在軌控制檯下面是命令集進出口運行：

2.0.0-p247 :084 > @doc = Doc.find(9) 
    Doc Load (0.7ms) SELECT `docs`.* FROM `docs` WHERE `docs`.`id` = 9 LIMIT 1 
=> #<Doc id: 9, created_at: "2014-07-14 16:42:54", updated_at: "2014-07-14 16:42:59", numrows: 761, user: "XXXX", source: nil, size: nil, location: "ABC.csv", status: "parsing_complete"> 


2.0.0-p247 :085 > @doc.rows 
NoMethodError: undefined method `rows' for #<Doc:0x007ff20c1b8860> 
    from /Users/XXXX/.rvm/gems/ruby-2.0.0-p247/gems/activemodel-4.0.2/lib/active_model/attribute_methods.rb:439:in `method_missing' 
    from /Users/XXXX/.rvm/gems/ruby-2.0.0-p247/gems/activerecord-4.0.2/lib/active_record/attribute_methods.rb:155:in `method_missing' 
    from (irb):85 
    from /Users/XXXX/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.2/lib/rails/commands/console.rb:90:in `start' 
    from /Users/xxxx/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.2/lib/rails/commands/console.rb:9:in `start' 
    from /Users/XXXX/.rvm/gems/ruby-2.0.0-p247/gems/railties-4.0.2/lib/rails/commands.rb:62:in `<top (required)>' 
    from bin/rails:4:in `require' 
    from bin/rails:4:in `<main>' 
2.0.0-p247 :086 > 


2.0.0-p247 :086 > Row.where(:doc_id => 9) 
    Row Load (31.7ms) SELECT `rows`.* FROM `rows` WHERE `rows`.`doc_id` = 9 
=> #<ActiveRecord::Relation [#<Row id: 1, created_at: "2014-07-14 16:42:57", updated_at: "2014-07-14 16:42:57", numCols: nil, type: nil, content: "[PROGRAMS] (All Locations|Consolidated),,,,,,,,,,,,...">,

，

....

因此Row對象存在。但是，我不能通過相應的Doc模型對象拉它們。

因爲我建立了所有的關聯。我想知道我沒有得到什麼招數

任何幫助，將不勝感激。

感謝

來源

2014-07-14 banditKing

所以在軌道4,5由於強PARAMS其不足以建立模型關係。還必須通過相應地設置「model_params」方法來允許檢索相關模型。

在這裏，我改變docs_controller/doc_params以下

 # Never trust parameters from the scary internet, only allow the white list through. 
     def doc_params 
      params.require(:doc).permit(:status, :user, :numrows, :size, :source, :location, :row_ids => []) 
     end

通知「row_ids => []」。那就是缺少的東西。現在一切都很好。

來源

2014-07-14 19:10:26 banditKing

Rails 4 - 兩個模型設置爲一對多關聯，但不能拉出與一個模型相關的所有記錄

，

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