Best methods for ingesting XML into Oracle 11gR2
The fastest way to get things in is via SQLLoader, also for XML. The following will show you a method based on bfilename, which should be able to load XML files into the database in around a minute or 2 per file.

https://forums.oracle.com/forums/thread.jspa?threadID=2284390&amp;tstart=30

You got some repeating elements in that file, so if you want to be able to query it efficient you should created specific, based on (x)path setting xmlindexes. 

Some extra info can be found here

forums.oracle.com/forums/thread.jspa?threadID=2234618&amp;tstart=120

If you need a short introduction into, or howto examples, search the needed info via blog.gralike.com

HTH

Marco