Reason: This is because the system default looks for commands in / usr / bin, if the command is not in this directory, of course, will not find the command, we need to do is to map a link under / usr / bin directory, which is equivalent establish a link file.
First of all have to know the full path to the command mysql or mysqladmin command, such as mysql path is: / usr / local / mysql / bin / mysql, we can execute this command:
ln -s /usr/local/mysql/bin/mysql /usr/bin