Manual:Oracle

Step 1. Install the Oracle client following this article http://www.oracle.com/technetwork/articles/technote-php-instant-084410.html

Step 2. Install Mediawiki and on the config page you should have the option to select an Oracle database connection. Note that you need to specify the DB Name as servername/SID if there is an error like "TNS: No Listener" then check the DBName setting....

Testdrive your wiki...