Question

Model: Product

has-many product-categories, :through => ...

Question 1) How do I index a many to many association with thinking sphinx

Must I use has?

Questions 2) How is this searched in the controller

ex. Product.search params[:search-params], :conditions => {some_conditions}

Answer 1

I’ve not tried this on a has_many :through so shoot me down in flames if you have, but I don’t see why this wouldn’t work for you too, (I’m using it on a has_many association) you basically use your association in the index definition. Then searches against that model will also search the child records.

class Product < ActiveRecord::Base
  has_many :product_categories

  define_index do
    indexes a_product_field_to_index
    indexes product_categories.name, :as => :categories
  end
end

In the controller:

@products = Product.search(params[:query] || '')
#params[:query] is simply the search string, I can't remember if you need to sanitize this, I would always assume you do unless you find out otherwise

In the view:

@products.each do |p| 
  p.categories.each do |cat|
  end
end

If you don’t already have it I would highly recommend the thinking-sphinx book available on peepcode: https://peepcode.com/products/thinking-sphinx-pdf

Hope that helps.