什么是和使用数据类型的例子 - 引用 [英] What is and examples of using data type - References

问题描述

我想知道数据类型参考以及一些关于如何/为什么在网站上使用的示例。如果他们是使用Ruby-on-Rails时的区别，我标记它，以防万一。我是一个新的编程，它将帮助极大地解释一切在外行的条款。

感谢帮助我的麻烦，谢谢。

<我想在迁移中指的是 t.references：associated_model 的解释方案？

假设有两个模型：Post和Author。

  ; ActiveRecord :: Base 
 belongs_to：author 
 end 
 
 class Author< ActiveRecord :: Base 
 has_many：posts 
 end 
  

您的迁移包含： / p>

  create_table：posts do | t | 
 t.references：author 
 end 
  

在 posts 表中使用整数数据类型<$ p>创建$ c> author_id >

在迁移中， t.belongs_to 是 t.references的一个别名并匹配用于在模型中设置关联的命名。

i wanted to know about the data type references and some examples of how/why it would be used on a website. If their is a difference when using Ruby-on-Rails, i tagged it just in case. I am new at programming and it would help tremendously to explain everything in layman's terms so i can slowly build my way up to being a computer wiz.

Appreciate the trouble in helping me, thanks.

解决方案

I'm taking a guess that you're referring to t.references :associated_model in a migration?

Suppose two models, Post and Author.

class Post < ActiveRecord::Base
  belongs_to :author
end

class Author < ActiveRecord::Base
  has_many :posts
end

Your migration contains:

create_table :posts do |t|
  t.references :author
end

This will create the author_id column on the posts table with the integer datatype.

In migrations, t.belongs_to is an alias for t.references and matches the naming used to set up the associations in your models.

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