ruby-on-rails - 具有祖先的 Rails 复杂搜索

Question

我有以下模型设置

class Category < ActiveRecord::Base

  has_ancestry :cache_depth => true, :depth_cache_column => :depth

  has_many :watches, :dependent => :destroy
  has_many :products, :through => :watches
end

class Watch < ActiveRecord::Base

  belongs_to :category
  has_many :products
end

class Product < ActiveRecord::Base

  belongs_to :watch, :counter_cache => true
  belongs_to :category
end

我需要通过类别名称查找产品。类别有 2 层深(树结构)。 1 - 级别是品牌，2 - 意甲。现在我在 meta_search gem

的帮助下构建这种类型的搜索查询

@products = (Product.search :watch_category_name_contains => params[:search]).all.paginate(:page => params[:page])

这有效并返回所有带有 serie_name 的产品。但是观察表总是只包含 2 级类别(系列)的 category_id，我需要能够通过品牌(1 级类别)搜索产品。我如何构建这种类型的查询？谢谢!

Answer 1

好吧，我看到有人对我的旧问题投赞成票，所以我会回答。我使用原始 sql 完成品牌和系列查询。在这里:

  def self.makes_with_products
    find_by_sql "
SELECT makes.* FROM categories makes
WHERE ancestry IS NULL AND makes.id IN (
    SELECT series.ancestry FROM products p
    INNER JOIN watches w ON w.id = p.watch_id
    INNER JOIN categories series ON series.id = w.category_id
    WHERE series.ancestry = makes.id AND p.active
  )
"
  end

  def series_with_products
   find_by_sql "
SELECT series.* FROM categories series
WHERE series.ancestry = '#{id}'
  AND (
    SELECT COUNT(*) FROM products p
    INNER JOIN watches w ON w.id = p.watch_id
    WHERE w.category_id = series.id AND p.active
  ) > 0
"
  end

希望这对某人有所帮助。