How can I make a has_many through work with multiple database connections?
I have a database named "master" that holds the location information. That is updated from a separate application. Users can have access to many locations, but all the other models are located in another database named "budget". Here are how the models are setup.
# place.rb
class Place < ActiveRecord::Base
belongs_to :user
belongs_to :location
end
# user.rb
class User < ActiveRecord::Base
has_many :locations, :through => :places
has_many :places
end
# location.rb
class Location < ActiveRecord::Base
establish_connection "master"
has_many :places
has_many :users, :through => :places
end
When I run commands through irb, I get the following
> Location.first.places.create(:user_id => 1)
> #<Place id: 1, user_id: 1, location_id: 1, created_at: "2011-11-28 20:58:43", updated_at: "2011-11-28 20:58:43">
> Location.first.places
> [#<Place id: 1, user_id: 1, location_id: 1, created_at: "2011-11-28 20:58:43", updated_at: "2011-11-28 20:58:43">]
> Location.first.users
> [#<User id: 1, username: "toby", role: "guest", created_at: "2011-11-28 17:45:40", updated_at: "2011-11-28 17:45:40">
> User.first.locations
> Mysql2::Error: Table 'master.places' doesn't exist: SELECT `locations`.* FROM `locations` INNER JOIN `places` ON `locations`.`id` = `places`.`location_id` WHERE `places`.`user_id` = 1 ActiveRecord::StatementInvalid: Mysql2::Error: Table 'master.places' doesn't exist: SELECT `locations`.* FROM `locations` INNER JOIN `places` ON `locations`.`id` = `places`.`location_id` WHERE `places`.`user_id` = 1
I tried adding the current rails env to Place to try and override the default database for place, like this: # place.rb class Place < ActiveRecord::Base establish_connection Rails.env belongs_to :user belongs_to :location end
#database.yml
master:
adapter: mysql2
encoding: utf8
reconnect: false
database: master
pool: 5
username: root
password:
socket: /var/run/mysqld/mysqld.sock
development:
adapter: mysql2
encoding: utf8
reconnect: false
database: budget_development
pool: 5
username: root
password:
socket: /var/run/mysqld/mysqld.sock
That didn't help. Any ideas?
A friend answered this for me, and I figured it might be of some use to others.
class Location < ActiveRecord::Base
#establish_connection "master"
def self.table_name() "master.locations" end
has_many :places
has_many :users, :through => :places
end