Ubuntu crashed tonight which urged me to reintsall the system and MySQL. Damn!
-------------------main procedure-------------------
shell> groupadd mysql
shell> useradd -g mysql mysql
shell> gunzip < mysql-VERSION.tar.gz | tar -xvf -
shell> cd mysql-VERSION
shell> ./configure --prefix=/usr/local/mysql
shell> make
shell> make install
shell> cp support-files/my-medium.cnf /etc/my.cnf
shell> cd /usr/local/mysql
shell> bin/mysql_install_db --user=mysql
shell> chown -R root .
shell> chown -R mysql var
shell> chgrp -R mysql .
shell> bin/mysqld_safe --user=mysql &
------------------
initilize the password ------------------
#set the password for root
shell> mysql -u root
mysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpwd');
#creat user mysql and set its password '123456'
CREATE USER mysql@localhost IDENTIFIED BY '123456';
GRANT ALL ON db_name.* TO mysql@localhost
References:
http://dev.mysql.com/doc/refman/5.1/zh/index.html