Thinking Sphinx indexing nested models

Question

I'm using Rails 3.2 and Thinking Sphinx 3. I have the following associated models:

# country.rb
class Country < ActiveRecord::Base
  has_many :states
end

# state.rb
class State < ActiveRecord::Base
  belongs_to :country
  has_many :state_shops
  has_many :shops, :through => :state_shops
end

# state_shop.rb
class StateShop < ActiveRecord::Base
  belongs_to :state
  belongs_to :shop
end

# shop.rb
class Shop < ActiveRecord::Base    
end

In country.rb, I wanna search the name of shop. Here is my index for country:

# country_index.rb
ThinkingSphinx::Index.define :country, :with => :active_record do
  indexes :name

  has budget, duration, overall_rating, created_at
end

How should my associated index be in order to search the shop.name?

Answer 1

You can pull in association columns in your index definitions pretty easily - here's an example for getting the shop names into the country index:

ThinkingSphinx::Index.define :country, :with => :active_record do
  indexes name
  indexes states.state_shops.shop.name, :as => :shop_names

  has budget, duration, overall_rating, created_at
end

I've given the field an alias, so it doesn't conflict with the existing name field (Sphinx will get confused otherwise).

A standard search will return any countries that match the country name or any of the associated shop names:

Country.search 'Australia'

But you can be a bit more specific if you're just looking for countries that match the query term to just any of the shop names:

Country.search :conditions => {:shop_names => 'Australia'}