我有一个模特

class Post < ApplicationRecord
  enum status: { pending: 'pending',accepted: 'accepted',cancelled: 'cancelled' }
end

在数据库中，我在数据库中的记录很少，当我进行group_by或计数时，我得到如下结果

Jayesh@rails:~/yashu$ rails c
Loading development environment (Rails 5.1.6.1)

[1] pry(main)> Post.group(:status).count
   (0.6ms)  SELECT COUNT(*) AS count_all,"posts"."status" AS posts_status FROM "posts" GROUP BY "posts"."status"
=> {"pending"=>5,"cancelled"=>1,"accepted"=>4}

现在如果我在模型中进行更新，则具有相同的数据集

class Post < ApplicationRecord
  enum status: { pending: 'pending',accepted: 'accepted' }
end

再做一次控制台查询，这三个查询给我下面的结果

[1] pry(main)> Post.group(:status).count
   (0.9ms)  SELECT COUNT(*) AS count_all,nil=>1,"accepted"=>4}

[2] pry(main)> Post.where(status: nil).count
   (1.3ms)  SELECT COUNT(*) FROM "posts" WHERE "posts"."status" IS NULL
=> 0

[3] pry(main)> Post.where(status: nil)
  Post Load (0.4ms)  SELECT "posts".* FROM "posts" WHERE "posts"."status" IS NULL
=> []

如果我找到该记录，就会看到如下图

[7] pry(main)> Post.find(8).status
  Post Load (0.4ms)  SELECT  "posts".* FROM "posts" WHERE "posts"."id" = $1 LIMIT $2  [["id",8],["LIMIT",1]]
=> nil

因此，我如何获取设置为nil的记录（如果确实如此），实际上是由于不同的开发人员在同一模型上工作，并向其枚举哈希添加不同的键并破坏了代码而引起的视图文件sample.html.erb post.status 中的某个时间点未显示（对于那些其键现在不在枚举哈希中，但记录在数据库中创建过一次的键）。