Question

I have read this isnt possible, and then someone else told me it is. They gave me this code but then had to go, now now my app is broken until I get this working :/

I have a Tag model, and each tag has_many resources :through => resource tags. Each resource also has_many tags.

I need to know the number of resource each tag has (I dont care about the other way around).

The problem is it says unkown key cache_counter

This is my model

Tag.rb

  has_many :resource_tags, :dependent => :destroy, :counter_cache => :resource_count
  has_many :resources, :through => :resource_tags

Resource.rb

  has_many :resource_tags, :dependent => :destroy
  has_many :tags, :through => :resource_tags

My migration:

class CreateTags < ActiveRecord::Migration
  def change
    create_table :tags do |t|

      t.string  :name
      t.integer :resource_count, :default => 0

      t.timestamps
    end
  end
end

Answer 1

:counter_cache option is for belongs_to method

in resorce_tag model

belongs_to :tag, :counter_cache => :resource_count

and i think it is better to name column resources_count (plural)