max_allowed_packet 的值太小,会导致插入和更新数据失败。
一、登录mysql查看当前配置
show VARIABLES like '%max_allowed_packet%';
+-------------------------------------+------------+
| Variable_name | Value |
+-------------------------------------+------------+
| max_allowed_packet | 1024 |
| slave_max_allowed_packet | 1073741824 |
+-------------------------------------+------------+
二、修改配置文件
1、直接修改配置文件(my.cnf)
max_allowed_packet=20M
注:如果找不文件,可以通过
mysql --help | grep my.cnf 命令查找文件
2、使用mysql命令修改
登录mysql
执行: set global max_allowed_packet = 2*1024*1024*10
退出命令行,重启mysql。
service mysqld stop (停止)
service mysqld start (启动)
service mysqld restart (重启)
3、检测是否修改成功
登录mysql
show VARIABLES like '%max_allowed_packet%';
+-------------------------------------+------------+
| Variable_name | Value |
+-------------------------------------+------------+
| max_allowed_packet | 1048576 |
| slave_max_allowed_packet | 1073741824 |
+-------------------------------------+------------+