You still need to install, at the least, the client software so that DBD::Oracle
can link against it. Most of the DBD::*s are just layers over the client libraries. Most are written in XS, for that very reason.
This, incidentally, is why most DBI work on Windows tends to use ODBC, because ActiveState has DBD::ODBC already compiled and most RDBMSes will talk in ODBC.
Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.