修改配置文件my.ini
将其改为：（路径根据自己mysql的安装路径进行适当调整，与字符编码无关，不必改动）
[mysqld]
basedir=C:\MYSQL57
datadir=C:\MYSQL57\data
character_set_server=utf8
collation-server=utf8_general_ci
[client]
default-character-set=utf8
重新启动mysql服务
执行SHOW VARIABLES LIKE 'character%';即可看到：
mysql> SHOW VARIABLES LIKE 'character%';
+--------------------------+----------------------------+
| Variable_name | Value |
+--------------------------+----------------------------+
| character_set_client | utf8 |
| character_set_connection | utf8 |
| character_set_database | utf8 |
| character_set_filesystem | binary |
| character_set_results | utf8 |
| character_set_server | utf8 |
| character_set_system | utf8 |
| character_sets_dir | C:\MYSQL57\share\charsets\ |
+--------------------------+----------------------------+
8 rows in set, 1 warning (0.00 sec)