Ruby on rails 从模型调用时预加载关联'；s法

假设我有一个简单的应用程序运行：

# model
class Project
    has_many :numbers

  def my_numbers
    numbers
  end
end

# controller
class ProjectController
  def index
    @projects = Project.includes(:numbers)
  end  
end

在我看来，没问题。我正在直接给协会打电话，所以所有号码都已加载

@projects.each do |project|
  project.numbers
  # no probleme here. Hit the cache of included numbers.
end

这是日志

Project Load (0.8ms)  SELECT "projects".* FROM "projects" 
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" IN (1,2)

Project Load (0.8ms)  SELECT "projects".* FROM "projects" 
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" IN (1,2)
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" = 1
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" = 2

但在第二个示例中，从Project中的方法调用中调用数字，每次调用my_numbers都会触发一个新的db调用，如下所示：

@projects.each do |project|
  project.my_numbers
end

这是日志

Project Load (0.8ms)  SELECT "projects".* FROM "projects" 
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" IN (1,2)

Project Load (0.8ms)  SELECT "projects".* FROM "projects" 
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" IN (1,2)
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" = 1
ProjectNumber Load (0.5ms)  SELECT "project_numbers".* FROM "project_numbers" WHERE "project_numbers"."project_id" = 2

有没有办法避免这种情况？为什么我的模型不重用第一个db请求中包含的数字

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提前谢谢

我已经在Rails 3.0.9中尝试了这段代码，但它没有实现您描述的行为。您确定数字没有触发回调吗？

我在Rails 3.0.9中尝试了这段代码，但它没有实现您描述的行为。您确定号码没有触发回调吗