I am currently developing a mountable engine. Within the engine I have the following two models:
module Ems
class Channel < ActiveRecord::Base
has_and_belongs_to_many :categories
end
end
module Ems
class Category < ActiveRecord::Base
has_and_belongs_to_many :channels
end
end
These are the db migration files:
class CreateEmsChannels < ActiveRecord::Migration
def change
create_table :ems_channels do |t|
t.string :slug
t.string :name
t.timestamps
end
end
end
class CreateEmsCategories < ActiveRecord::Migration
def change
create_table :ems_categories do |t|
t.string :slug
t.string :name
t.text :strapline
t.timestamps
end
end
end
class CreateEmsCategoriesChannels < ActiveRecord::Migration
def up
# Create the association table
create_table :ems_categories_channels, :id => false do |t|
t.integer :category_id, :null => false
t.integer :channel_id, :null => false
end
# Add table index
add_index :ems_categories_channels, [:category_id, :channel_id], :unique => true
end
end
The problem starts when I try to retrieve the associated objects.
As an example, when I call @channel.get :categories
I get the following error:
Mysql2::Error: Table 'ems_development.categories_channels' doesn't exist:
SELECT `ems_categories`.*
FROM `ems_categories`
INNER JOIN `categories_channels`
ON `ems_categories`.`id` = `categories_channels`.`category_id`
WHERE `categories_channels`.`channel_id` = 1
As you can see its missing off the isolate_namespace value on the link table, as it should look for the association on the table ems_categories_channels
not categories_channels
Anyone had similar problems or am I missing something?
You can explicitly set the join table name (per the documentation).
module Ems
class Channel < ActiveRecord::Base
has_and_belongs_to_many :categories, :join_table => 'ems_categories_channels'
end
end
module Ems
class Category < ActiveRecord::Base
has_and_belongs_to_many :channels, :join_table => 'ems_categories_channels'
end
end
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