There is so much wrong with this presentation. Datafiles do NOT automatically have .dbf extensions and they don't NEED to. Datafiles, controlfiles, redo logs should NOT be stored in $ORACLE_BASE/oradata/<SID> they should be stored on a separate device away from any of the Oracle executables and libraries. Redo logs should NOT have a .log extension since some System Administrators have deleted to reclaim file system space. The new 'standard' is to use the .rdo extension. Also this presentation has mixed two marketing names for Oracle, '10g' and '11g'. neither of which is any indication of the actual database version. If new database administrators follow the path you have tried to set with this presentation performance problems would be inevitable. More accurate information needs to be presented.