hide the commabd executed from ps,who

[50191914]

How can I hide the commond I am executing so that people can't see
it from ps,or who?For example,if i use mysql by typing mysql -u myname -p
passsword ..people can see my password...So it would be good if I can
hide what i am doing from other user...espcially for some program which 
I can specify my password in command line...