https://blog.csdn.net/niqinwen/article/details/8693044

導入數據庫的時候 SQLyog 報錯了

Error Code: 2006 – MySQL server has gone away

搜了下，說是max_allowed_packet （MySQL的一個參數）設置的值不夠大。

那我改下就行了 嘿嘿

In Windows:

In the MySQL server installation directory,
in my.ini file, add the following line under [mysqld] in SERVER SECTION.

max_allowed_packet = 16M

In Linux:

Copy the my-xxx.cnf file from /usr/share/mysql to /etc as my.cnf

xxx can be small, medium, large, huge … depending on the requirement.

$ cp /usr/share/mysql/my-xxx.cnf /etc/my.cnf

In the my.cnf file, change the default
max_allowed_packet = 1M
to
max_allowed_packet = 16M

Save the file and restart MySQL server.

今天導入.sql文件時出現了Error Code: 2006 – MySQL server has gone away錯誤，原來是導入的sql文件大於系統默認的max_allowed_packet的值，查了很多修改配置文件的，但是沒有找到my.cfg文件，修改其他文件不管用，所以直接使用sql語句來修改：

SET GLOBAL max_allowed_packet=67108864;

這個挺好使的，改完之後不用重啟服務，直接好使了

SQLyog恢復數據庫報錯解決方法【Error Code: 2006 - MySQL server has gone away】