仅为某些 ActiveRecord 查询禁用 Rails STI

Question

我可以为整个模型禁用 STI，但我只想在执行某些查询时禁用它。在 Rails 3.2 中一切正常，但我已经升级到 Rails 4.1.13 并且发生了一件打破查询的新事情。

我有一个名为 Person 的基础 class，其作用域相当复杂。

class Person < ActiveRecord::Base
  include ActiveRecord::Sanitization
  has_many :approvals, :dependent => :destroy
  has_many :years, through: :approvals

  scope :for_current_or_last_year, lambda {
      joins(:approvals).merge(Approval.for_current_or_last_year) }

  scope :for_current_or_last_year_latest_only, ->{
      approvals_sql = for_current_or_last_year.select('person_id AS ap_person_id, MAX(year_id) AS max_year, year_id AS ap_year_id, status_name AS ap_status_name, active AS ap_active, approved AS ap_approved').group(:id).to_sql
      approvals_sql = select("*").from("(#{approvals_sql}) AS ap, approvals AS ap2").where('ap2.person_id = ap.ap_person_id AND ap2.year_id = ap.max_year').to_sql

    select("people.id, ap_approved, ap_year_id, ap_status_name, ap_active").
    joins("JOIN (#{approvals_sql}) filtered_people ON people.id =    
      filtered_people.person_id").uniq
  }
end

并继承 classes 称为 Member 和 Staff。唯一与此相关的事情我不得不注释掉以使我的测试通过Rails 4。这可能是问题所在，但在这种情况下取消注释并没有帮助。

class Member < Person
    #has_many :approvals, :foreign_key => 'person_id', :dependent => :destroy, :class_name => "MemberApproval"
end

当我查询时出现问题Member.for_current_or_last_year_latest_only

我收到错误 unknown column 'people.type'

当我查看 SQL 时，我可以看到问题所在的行，但我不知道如何删除它或使其正常工作。

Member.for_current_or_last_year_latest_only.to_sql 结果。

SELECT DISTINCT people.id, ap_approved, ap_year_id, ap_status_name, ap_active 
FROM `people` 
JOIN (SELECT * FROM (SELECT person_id AS ap_person_id, MAX(year_id) AS max_year, year_id AS ap_year_id, status_name AS ap_status_name, active AS ap_active, approved AS ap_approved 
  FROM `people` INNER JOIN `approvals` ON `approvals`.`person_id` = `people`.`id` 
WHERE `people`.`type` IN ('Member') AND ((`approvals`.`year_id` = 9 OR `approvals`.`year_id` = 8)) 
GROUP BY `people`.`id`) AS ap, approvals AS ap2

WHERE `people`.`type` IN ('Member') AND (ap2.person_id = ap.ap_person_id AND ap2.year_id = ap.max_year)) filtered_people ON people.id = filtered_people.person_id

WHERE `people`.`type` IN ('Member')

如果我从倒数第二个 WHERE 子句的开头删除 people.type IN ('Member') AND，查询将成功运行。顺便说一句，那部分不在从旧的 Rails 3.2 代码生成的查询中，它上面的那个也不在（只有最后一个匹配 Rails 3.2 查询）。问题是，那部分是从我假设的 rails 单 Table 继承生成的，所以我不能只从查询中删除它。它不是唯一添加到原始查询中的地方，但这是唯一导致它中断的地方。

有没有人知道我如何才能仅对某些查询禁用 STI 或向我的查询中添加一些内容以使其正常工作？我尝试将 people.type 放入每个 SELECT 查询中以尝试使其可用但无济于事。

感谢您抽出宝贵时间查看此内容。

Answer 1

我显然使这比实际更难...我只需要将 unscoped 添加到两个 approval_sql 子查询的前面。感谢您帮助我的大脑换档。

仅为某些 ActiveRecord 查询禁用 Rails STI

Disable Rails STI for certain ActiveRecord queries only

ruby

activerecord

ruby-on-rails

sti