version: rails4
3 创建Active Record 模型
创建Active Record models是非常简单的。你所需要做的就是实现 ActiveRecord::Base的子类, 你可以参考下面:
classProduct < ActiveRecord::Base end |
这会创建一个Product model,在数据库中映射一个products数据表。你将能够映射数据表每一行的列对应于模型实例的特性。正如同products数据表是用下文的SQL语句来创建的:
CREATETABLEproducts ( id int(11) NOTNULLauto_increment, namevarchar(255), PRIMARYKEY (id) ); |
基于上文的数据表模式,你将能够编写如下的代码:
p = Product.new p.name = "Some Book" puts p.name # "Some Book" |
original text: http://guides.rubyonrails.org/active_record_basics.html#creating-active-record-models
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