如何基于HABTM关联rails 4在连接表中插入数据

Question

我在炼油厂cms中创建了一个HABTM协会，但它返回的错误如下所示：

ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR:  relation "refinery_georgiantoast_restaurant_wines" does not exist
LINE 5:                WHERE a.attrelid = '"refinery_georgiantoast_r...
                                          ^
:               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                     pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
                FROM pg_attribute a LEFT JOIN pg_attrdef d
                  ON a.attrelid = d.adrelid AND a.attnum = d.adnum
               WHERE a.attrelid = '"refinery_georgiantoast_restaurant_wines"'::regclass
                 AND a.attnum > 0 AND NOT a.attisdropped
               ORDER BY a.attnum

/vendor/extensions/georgiantoasts/app/models/refinery/georgiantoast/restaurant.rb

下面是我的restaurant.rb模型：

module Refinery
  module Georgiantoast
    class Restaurant < Refinery::Core::BaseModel

      validates :title, :presence => true, :uniqueness => true

      belongs_to :avatars, :class_name => '::Refinery::Image'

      has_many :restaurants_wines

      has_many :wines, :through => :restaurants_wines

      # To enable admin searching, add acts_as_indexed on searchable fields, for example:
      #
      #   acts_as_indexed :fields => [:title]

    end
  end
end

/vendor/extensions/georgiantoasts/app/models/refinery/georgiantoast/wine.rb

下面是我的wine.rb模型：

module Refinery
  module Georgiantoast
    class Wine < Refinery::Core::BaseModel

      validates :title, :presence => true, :uniqueness => true

      belongs_to :avatars, :class_name => '::Refinery::Image'

      has_many :restaurants_wines

      has_many :restaurants, :through => :restaurants_wines

      # To enable admin searching, add acts_as_indexed on searchable fields, for example:
      #
      #   acts_as_indexed :fields => [:title]

    end
  end
end

/vendor/extensions/georgiantoasts/app/models/refinery/georgiantoast/restaurant_wines.rb

这是我的连接表模型restaurant_wines.rb

module Refinery
  module Georgiantoast
    class RestaurantWine < Refinery::Core::BaseModel

      belongs_to :wine

      belongs_to :restaurant

      # To enable admin searching, add acts_as_indexed on searchable fields, for example:
      #
      #   acts_as_indexed :fields => [:title]

    end
  end
end

/vendor/extensions/georgiantoasts/app/controllers/refinery/georgiantoast/admin/restaurants_controller.rb

这里是restaurants_controller.rb控制器：

module Refinery
  module Georgiantoast
    module Admin
      class RestaurantsController < ::Refinery::AdminController

        crudify :'refinery/georgiantoast/restaurant'

        private

        # Only allow a trusted parameter "white list" through.
        def restaurant_params
          params.require(:restaurant).permit(:title, :description, :address, :town, :state, :lat, :lng, :avatars_id, :wine_ids => [])
        end
      end
    end
  end
end

/vendor/extensions/georgiantoasts/app/views/refinery/georgiantoast/admin/restaurants/_form.html.erb

这是餐厅_form.html.erb表单：

<%= form_for [refinery, :georgiantoast_admin, @restaurant] do |f| -%>
    <%= render '/refinery/admin/error_messages',
               :object => @restaurant,
               :include_object_name => true %>

    <div class='field'>
      <%= f.label :title -%>
      <%= f.text_field :title, :class => 'larger widest' -%>
    </div>

    <div class='field'>
      <%= render '/refinery/admin/wysiwyg',
                 :f => f,
                 :fields => [:description],
                 :object => "georgiantoast/restaurant" -%>
    </div>

    <div class='field'>
      <%= f.label :address -%>
      <%= f.text_field :address -%>
    </div>

    <div class='field'>
      <%= f.label :wine -%>
      <%= select_tag "#{f.object_name}[wine_ids][]", options_for_select(Refinery::Georgiantoast::Wine.all.collect { |wine| [wine.title, wine.id] }), {multiple: true} -%>
    </div>


    <%= render '/refinery/admin/form_actions', :f => f,
               :continue_editing => false,
               :delete_title => t('delete', :scope => 'refinery.restaurants.admin.restaurants.restaurant'),
               :delete_confirmation => t('message', :scope => 'refinery.admin.delete', :title => @restaurant.title) -%>
<% end -%>

下面是迁移文件：

class CreateJoinTableRestaurantsWines < ActiveRecord::Migration
  def change
    create_join_table :restaurants, :wines do |t|
      t.index :restaurant_id
      t.index :wine_id
    end
  end
end

当我发布表单时，它没有执行任何调用联接表的操作。

如果我试图在rails console上运行以下命令，它将返回以下错误：

2.2.3 :001 > r = Refinery::Georgiantoast::Restaurant.first
  Refinery::Georgiantoast::Restaurant Load (1.0ms)  SELECT  "refinery_georgiantoast_restaurants".* FROM "refinery_georgiantoast_restaurants"  ORDER BY "refinery_georgiantoast_restaurants"."id" ASC LIMIT 1
 => #<Refinery::Georgiantoast::Restaurant id: 1, title: "abc restaurant", description: "<p>abc restaurant</p>", address: "12 helifax estate", town: "helifax", state: "toronto", lat: #<BigDecimal:55fdfc0,'-0.12555555E2',18(27)>, lng: #<BigDecimal:55fde80,'0.74555555E2',18(27)>, avatars_id: 3, position: nil, created_at: "2016-08-27 11:26:29", updated_at: "2016-08-27 11:26:29"> 
2.2.3 :002 > r.wine_ids
ActiveRecord::StatementInvalid: PG::UndefinedTable: ERROR:  relation "refinery_georgiantoast_restaurant_wines" does not exist
LINE 5:                WHERE a.attrelid = '"refinery_georgiantoast_r...
                                          ^
:               SELECT a.attname, format_type(a.atttypid, a.atttypmod),
                     pg_get_expr(d.adbin, d.adrelid), a.attnotnull, a.atttypid, a.atttypmod
                FROM pg_attribute a LEFT JOIN pg_attrdef d
                  ON a.attrelid = d.adrelid AND a.attnum = d.adnum
               WHERE a.attrelid = '"refinery_georgiantoast_restaurant_wines"'::regclass
                 AND a.attnum > 0 AND NOT a.attisdropped
               ORDER BY a.attnum

    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql_adapter.rb:592:in `async_exec'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql_adapter.rb:592:in `block in exec_no_cache'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract_adapter.rb:472:in `block in log'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/abstract_adapter.rb:466:in `log'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql_adapter.rb:592:in `exec_no_cache'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql_adapter.rb:584:in `execute_and_clear'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql/database_statements.rb:160:in `exec_query'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql_adapter.rb:733:in `column_definitions'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/postgresql/schema_statements.rb:197:in `columns'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/schema_cache.rb:43:in `columns'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/connection_adapters/schema_cache.rb:49:in `columns_hash'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/associations/association_scope.rb:85:in `column_for'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/associations/association_scope.rb:94:in `bind'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/associations/association_scope.rb:103:in `last_chain_scope'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activerecord-4.2.6/lib/active_record/associations/association_scope.rb:139:in `add_constraints'
... 9 levels...
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/railties-4.2.6/lib/rails/commands/console.rb:9:in `start'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/railties-4.2.6/lib/rails/commands/commands_tasks.rb:68:in `console'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/railties-4.2.6/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/railties-4.2.6/lib/rails/commands.rb:17:in `<top (required)>'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `require'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `block in require'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:240:in `load_dependency'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `require'
    from /home/muhammad/workspace/georgian-toast-wines/bin/rails:9:in `<top (required)>'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:268:in `load'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:268:in `block in load'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:240:in `load_dependency'
    from /home/muhammad/.rvm/gems/ruby-2.2.3@georgian-toast/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:268:in `load'
    from /home/muhammad/.rvm/rubies/ruby-2.2.3/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
    from /home/muhammad/.rvm/rubies/ruby-2.2.3/lib/ruby/site_ruby/2.2.0/rubygems/core_ext/kernel_require.rb:54:in `require'
    from -e:1:in `<main>'

所有迁移都已经运行，也没有任何迁移或种子等待。

Answer 1

如果你使用form_for，你可以在你的视图应用程序/视图/餐馆/_表单中使用下面的内容

 <%= f.collection_select :wine_ids, @wines, :id, :name, {}, {:multiple => true} %>

别忘了在你的控制器里

 params.require(:restaurant).permit(:name, :wine_ids => [])

Answer 2

你似乎在葡萄酒和餐厅的课程中出现了一个错误。这种关系应该是通过restaurant_wines而不是restaurants_wines (所以只有“葡萄酒”应该是复数的)。

如果还没有这样做，则需要将wine_id和restaurant_id列添加到联接表中。一旦他们到了，你就应该

Answer 3

我知道这是个老生常谈的问题，但我遇到了一些我认为类似的问题，所以我会留下我的答案，以防对别人有帮助。

我相信，在为join表进行迁移时，您正在创建一个restaurants_wines表，但是精炼厂希望它被称为refinery_restaurants_wine，或者从您的错误中可以看到是refinery_georgiantoast_restaurants_wine。改到

class CreateJoinTableRestaurantsWines < ActiveRecord::Migration
  def change
    create_join_table :restaurants, :wines, table_name: "refinery_georgiantoast_restaurants_wine" do |t|
      t.index :restaurant_id
      t.index :wine_id
    end
  end
end

应该能起作用。