修改MySQL 5.5的max_allowed_packet属性的方法_MySQL
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修改MySQL 5.5的max_allowed_packet属性的方法
今天在部署一个实验系统的时候，报出下面这个错：
Your 'max_allowed_packet' variable is set to less than 16777216 Byte (16MB).
也很容易理解，就是需要修改一下MySQL的配置文件，但是这里面有个小技巧（在Windows 7中）：如果直接使用记事本或notepad++打开MySQL 5.5文件夹底下的my.ini，会提示该文件被其他程序占用，或者拒绝访问之类的（如：“please check if this file is opended in another program”）。如果已经停止了MySQL服务，那么其实就不是程序占用的问题。解决方法也很简单，首先，在MySQL 5.5安装目录下，将my.ini剪切到别处，这时会要求用管理员身份继续。
然后呢，在MySQL 5.5安装目录下，有很多和my.ini类似的文件，如my-small.ini，使用管理员身份启动某个文本编辑软件（如notepad++），将my.ini和my-small.ini都打开，将my-small.ini里面的这几行：
[plain]
[mysqldump]
quick
max_allowed_packet = 16M
拷贝到my.ini文件中，然后就可以保存成功了。再使用管理员身份拷贝到MySQL 5.5安装目录下，就可以实现我们的目的了。
就这么简单，记录一下。
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