有一张表，结构如下：

MariaDB [test]> show create table dept;
+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table                                                                                                                                                                                                    |
+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| dept  | CREATE TABLE `dept` (`dept_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '部门编号',`dept_name` char(20) DEFAULT NULL COMMENT '部门名称',PRIMARY KEY (`dept_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 |
+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.007 sec)

向其中插入一条带有中文的记录：

insert into dept(dept_name) values('销售部'),('财务部'),('生产部'),('人事部');

失败报错：

ERROR 1366 (22007): Incorrect string value: '\xCF\xFA\xCA\xDB\xB2\xBF' for column `test`.`dept`.`dept_name` at row 1

查看系统状态：

MariaDB [test]> status
--------------
mysql  Ver 15.1 Distrib 10.5.15-MariaDB, for Win64 (AMD64), source revision 9aa3564e8a06c3d2027fc514213ecf42b049b06eConnection id:          3
Current database:       test
Current user:           root@localhost
SSL:                    Not in use
Current pager:          stdout
Using outfile:          ''
Using delimiter:        ;
Server:                 MariaDB
Server version:         10.5.15-MariaDB mariadb.org binary distribution
Protocol version:       10
Connection:             localhost via TCP/IP
Server characterset:    latin1
Db     characterset:    latin1
Client characterset:    gbk
Conn.  characterset:    gbk
TCP port:               3306
Uptime:                 16 min 45 sec

原因是UTF-8编码可能是2个字节，3个字节，4个字节，mariadb的UTF8最多3个字节，所以插入失败。（Mariadb插入数据报错：ERROR 1366 (22007)_error 1366(22007)-CSDN博客）

解决般法参考（【数据库】MySQL 修改表默认字符集和排序规则，请谨慎操作、按照建议操作_更改数据表字符集和排序规则会锁表嘛-CSDN博客）：

ALTER TABLE dept CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci;

修改后表的结构变成了：

MariaDB [test]> show create table dept;
+-------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Table | Create Table                                                                                                                                                                                                                     |
+-------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| dept  | CREATE TABLE `dept` (`dept_id` int(11) NOT NULL AUTO_INCREMENT COMMENT '部门编号',`dept_name` char(20) DEFAULT NULL COMMENT '部门名称',PRIMARY KEY (`dept_id`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8mb4 |
+-------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.000 sec)