Rubyonrails 在Ruby on rails中，重复访问ActiveRecordModel返回相同的对象：预期行为还是错误

此行为是故意的.您正在关系上调用test2个方法，这意味着它充当一个作用域，而不仅仅是一个方法调用:

100

>> puts MyModel.where(some_column: "A").method(:test2).source
def #{method}(...)
  scoping { klass.#{method}(...) }
end

注意，方法调用通过scoping方法委托给MyModel.test2.

将所有查询的范围限定为当前范围.

Comment.where(post_id: 1).scoping do
  Comment.first
end
# SELECT "comments".* FROM "comments" WHERE "comments"."post_id" = 1 ORDER BY "comments"."id" ASC LIMIT 1

100

class MyModel < ApplicationRecord
  def self.test
    MyModel.where(some_column: "A").test2
  end

  def self.test2
    all.each do |my_model|
      my_model.update(some_column: "B")

      # NOTE: when you do this, `current_scope` is taken into account
      #       which you can take a look at:
      p "current_scope"
      p current_scope.to_sql
      MyModel.find(my_model.id)
    end
  end
end
#=>
# "current_scope"
# "SELECT \"my_models\".* FROM \"my_models\" WHERE \"my_models\".\"some_column\" = 'A'"

你可以用MyModel.unscoped.find(my_model.id)，但我不明白你为什么要这么做.此外，您也不能将方法调用链接到关系:

class MyModel < ApplicationRecord
  def self.test
    MyModel.where(some_column: "A")
  end

  def self.test2 q
    q.each do |my_model|
      my_model.update(some_column: "B")
      MyModel.find(my_model.id)
    end
  end
end

>> MyModel.test2(MyModel.test)