mysql - 在 RoR 中连接表

Question

我有以下两个型号。

class ResponseMap < ActiveRecord::Base
has_many :response, foreign_key: 'map_id', dependent: :destroy
belongs_to :reviewer, class_name: 'Participant', foreign_key: 'reviewer_id'


class Response < ActiveRecord::Base
include ResponseAnalytic

belongs_to :response_map, class_name: 'ResponseMap', foreign_key: 'map_id'

我必须加入这两个模型，并在 ResponseMap 中找到特定审阅者给出的响应，使得 response.map_id = responseMap.id。这是我需要将其转换为 ResponseMap 模型的事件记录查询的 SQL 查询。

select * from response_maps as rm join responses as r on r.map_id = rm.id where rm.reviewer_id = 97 

谁能帮我解决这个问题吗？

Answer 1

首先需要纠正关联

class ResponseMap < ActiveRecord::Base
  has_many :responses, foreign_key: 'map_id', dependent: :destroy
  belongs_to :reviewer, class_name: 'Participant', foreign_key: 'reviewer_id'

如果您有一个 has_many 关联，则名称应该是复数。

查询

ResponseMap.joins(:responses).where(reviewer_id: 97)