CentOS_XAMPP How to Set mySQL Environment Variable?

[sakibnaz]

Hello.
I am very new on linux platform. I have successfully installed XAMPP on CentOS. I can access PHPMyadmin from my browser. So my mySQL installation is OK.
I need to set Environment Variable. I am confused about the path directory.

For an example in windows the path was:

%MYSQL_HOME% -------> C:\xampp\mysql

What will be the path for CentOS $MYSQL_HOME?
Under LAMPP folder I did not see the "mysql" folder, I am confused. Need suggestion please. Thanks.

Regards.
Sakibnaz.