MySQL5.6时间类型timestamp和datetime有了重大改变
在MySQL5.5里（或更老的版本MySQL5.1）timestamp类型一个表里只允许一列字段拥有自动插入时间和自动更新时间、或只允许一列字段有自动插入时间，网站空间，另一列字段不能有自动更新时间。
但从MySQL5.6里，打翻了这一传统理念，香港服务器，香港虚拟主机，以上条件均可以出现，并且datetime类型也拥有了timestamp类型的功能。
相关mysql视频教程推荐：《mysql教程》
以下是演示：
这是MySQL5.5的（timestamp类型一个表里只允许一列字段拥有自动插入时间和自动更新时间）：
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