mysql max_allowed_packet 限制

Caused by: com.mysql.jdbc.PacketTooBigException: Packet for query is too large (1314 > 1024). You can change this value on the server by setting the max_allowed_packet' variable.

MySQL根据配置文件会限制Server接受的数据包大小。有时候大的插入和更新会受 max_allowed_packet 参数限制，导致写入或者更新失败。

查看目前配置：

show VARIABLES like '%max_allowed_packet%';
+--------------------+---------+
| Variable_name      | Value   |
+--------------------+---------+
| max_allowed_packet | 1048576 |
+--------------------+---------+ 

以上说明目前的配置是：1M

1.修改配置文件:my.cnf在[mysqld]段或者mysql的server配置段进行修改

max_allowed_packet = 20M

2.在mysql命令行中修改

set global max_allowed_packet = 2*1024*1024*10