Default Value of PATH in Linux environment variable

After modifying the PATH value in the/etc/profile file of RedHat Enterprise 5.7 today, run source/etc/profile, then all the commands, such as su, sudo, vi, gedit, find, and source, cannot be executed, and the prompt "xxx: command not found" is displayed ", later I thought it was caused by modifying the PATH value of the environment variable in/etc/profile, so I searched for it on the Internet and marked it to leave it for backup:

Export PATH =/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin