Question

我有以下关联：

#models/contact.rb
class Contact < ActiveRecord::Base
  has_many :relationships
  has_many :locations, through :relationships
end

#models/relationship.rb
class Relationship < ActiveRecord::Base
  belongs_to :contact
  belongs_to :location
end

#models/location.rb
class Location < ActiveRecord::Base
  has_many :relationships
  has_many :contacts, through: :relationships
end

我想要做的是创建一个范围，找到与contacts ID数组关联的所有location。

我试过这个范围，但它没有用。它正确连接表，但我传入的数组似乎造成了一些麻烦。我在where子句中的语法似乎有问题。

#models/Contact.rb
class Contact < ActiveRecord::Base
  ...
  scope :by_locations, ->(ids_ary){joins(relationships: :location).where("locations.id IN ?", ids_ary)}
end

Answer 1

除了其他答案之外，您还可以重写查询以改为使用哈希：

scope :by_locations, ->(ids_ary) { joins(relationships: :location).where("locations.id" => ids_ary) }

Answer 2

需要在问号周围添加括号：

scope :by_locations, ->(ids_ary){joins(relationships: :location).where("locations.id IN (?)", ids_ary)}

has_many上的范围，：通过与id数组的关系

2 个答案: