Rails validates_uniqueness_of，逻辑与

Question

I have three paramaters, eg site_id_1 and site_id_2. and transport_distance

When creating a new record, rails should validate that site_id_1 AND site_id_2. dont already exist. (So the combination matters)

With validates_uniqueness_of(:site_id_1, :site_id_2) it says that site_id_1 or site_id_2 already exist. I've also tried: validates_uniqueness_of(:site_id_1 && :site_id_2) but it doesnt helped me.

Answer 1

您应该使用validates_uniqueness_of验证程序的scope参数：

validates_uniqueness_of :site_id_1, scope: :site_id_2

Answer 2

Rails 4样式：

validates :site_id_1, uniqueness: {scope: :site_id_2}