Changing databases from MySQL to Oracle

I am new to PHP and am trying to learn how it works. We have a PHP program that is using MySQL. We are wanting to use our Oracle database instead. The Oracle database is on a different server that our PHP program. Does any one know how I can change connections from MySQL to Oracle? We have this line in our dba.php....... $tli_connection = dbconnect($dsn, $user, $pass); In our config.php we have the following that defines the above............ $dsn = "some.where.com"; // MySQL hostname (something@somewhere..someextension) $user = "MYSQL USER NAME GOES HERE"; // Username with sufficient rights to the DB - need update, select, delete, insert only $pass = "MYSQL PASSWORD FOR ABOVE USER"; // Password for the above user Thanks Jan Smith Systems Analyst Indiana State University Terre Haute, Indiana Phone: (812) 237-8593 Email: jsmith7@isugw.indstate.edu