本人使用mysql5.7，前端插入数据库中文时显示？？？，修改数据连接字符编码和数据库字段编码改为utf-8，都不行，最后MySQL在修改了以下配置后，显示正常了。
set character_set_client = utf8;
set character_set_server = utf8;
set character_set_connection = utf8;
set character_set_database = utf8;
set character_set_results = utf8;
set collation_connection = utf8_general_ci;
set collation_database = utf8_general_ci;
set collation_server = utf8_general_ci;
