mysql 旧版本升级至4.1以上版本的时候，当出现以下错误： client does not support authentication protocol requested
by server; consider upgrading mysql client
其实这是因为mysql4.1以后，密码的加密算法不一样了的缘故。
解决办法：use mysql; update user set password=old_password('new_password') where host='%' and user='some_user'; flush privileges;
2、命令方法
mysql> update mysql.user set password = old_password('new_password') where host='%' and user = 'some_user';
1、sql方法