gistfile1.rb

def nationwide_search
  category_ids = self.category_ids
  Business.search do |search|
    search.any_of do
       with :category_ids, category_ids unless category_ids.blank?
       with :category_ids, nil
    end  
    search.keywords query
    search.order_by :name if order == :alpha
    search.order_by :review_count, :desc if order == :review_count
    search.order_by :stars, :desc if order == :rating
    search.paginate :page => page, :per_page => per_page
  end
end