Question

我有一个Hotel模型和HotelAmenity模型以及Amenity模型，它们与has_many :through相关联：

class Hotel < ActiveRecord::Base
    has_many :hotel_amenities, :dependent => :destroy
    has_many :amenities, through: :hotel_amenities
end

class Amenity < ActiveRecord::Base
    has_many :hotel_amenities, :dependent => :destroy
    has_many :hotels, through: :hotel_amenities
end


class HotelAmenity < ActiveRecord::Base
  belongs_to :amenity
  belongs_to :hotel
end

现在我的行动中有hotel_id，我想要抓取所有有设施的酒店[1,2,3]这是array的{{1}}。

Answer 1

好问题!! 不用担心，您可以使用join上的Hotel Model解决此问题：首先，您可以通过hotel_id

找到酒店

@hotel= Hotel.find_by_id(params[:user_id))

现在，您可以找到amenity_array [1,2,3]

的酒店

 @hotels = @hotels.joins(:hotel_amenities).where(hotel_amenities: { amenity_id: [1,2,3] }) // this can returns a hotel two or more time


@hotels = @hotels.joins(:hotel_amenities).where(hotel_amenities: { amenity_id: [1,2,3] }).uniq // this will return all hotels without redundant records

希望这对你有用。

Answer 2

试试这段代码：

arr= [1,2,3] 
Hotel.joins(:hotel_amenities).select("hotel_amenities.*,hotels.*").where("hotel_amenities.amenity_id= ?",arr)

使用has_many：through关系连接获取记录

2 个答案: