出现1251错误是因为，MySQL8.0版本改变了密码的验证规则caching_sha2_password，MySQL之前的版本验证规则是mysql_native_password，现在需要修改MySQL8的验证规则。ALTER USER 'root'@'localhost' IDENTIFIED BY 'password' PASSWORD EXPIRE NEVER; #修改加密规则 、
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '新密码'; #更新一下用户的密码
FLUSH PRIVILEGES; #刷新权限