一.su --run a shell with substitute user and group IDs -,-l,--login make the shell a login shell, clears all envvars except forTERM, initializes HOME, SHELL, USER, LOGNAME and PATH 带-参数和不带-参数切换用户示例: -c, --command=COMMAND pass a single COMMAND to the s
修改密码: mysql> grant all privileges on *.* to yongfu_b@'192.168.1.%' identified by 'my_password_new'; 新建用户: mysql> grant all privileges on *.* to yongfu_b@'192.168.1.%' identified by 'my_password_2';