用mysqladmin
格式:mysqladmin -u用户名 -p旧密码 password 新密码
例子:mysqladmin -uroot -p123456 password 123
net start mysql
Qt 无法连接数据库mysql
https://blog.youkuaiyun.com/yy64578537/article/details/71006042
把libmysql.dll 拷贝到 D:\Qt\Qt5.9.8\5.9.8\mingw53_32\bin
https://download.youkuaiyun.com/download/linbounconstraint/11829144