具有多个且属于RAILS 3的复杂查询
||
我试图在控制器中进行查询，以获取具有类别ID的供应商列表。
我有这样的模型设置。
class Supplier < ActiveRecord::Base
has_and_belongs_to_many :sub_categories
end
class Category < ActiveRecord::Base
has_many :sub_categories
end
class SubCategory < ActiveRecord::Base
belongs_to :category
has_and_belongs_to_many :suppliers
end
@supplier.sub_categories.first.category.name
@category = Category.find(params[:category_id])
@suppliers = Supplier.where(\'sub_category.first.category.id = ?\', @category.id)
Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near \'.id = 20)\' at line 1: SELECT `suppliers`.* FROM `suppliers` WHERE (sub_category.first.category.id = 20)
没有找到相关结果
已邀请:
1 个回复
徐百晴墓斜
Supplier.joins(:sub_category_suppliers => :sub_categories). where(\'sub_categories.category_id =?\', @category.id). group(\'suppliers.id\')scope :by_category, lambda { |category_id| joins(:sub_category_suppliers => :sub_categories). where(\'sub_categories.category_id =?\', category_id). group(\'suppliers.id\') }