Cache problem

product.rb

class Product < StatisticsModel

    has_one :active_sale, :class_name => 'Sale', :foreign_key => 'product_id', :conditions => ["sales.start_date <= ? AND (sales.end_date IS NULL OR sales.end_date > ?)", Time.zone.now, Time.zone.now], :order => "sales.start_date desc"

end

product_statistic.rb

class ProductStatistic < ActiveRecord::Base

  attr_protected

  belongs_to :product
  
end