What is the first thing you do when a new version of an Oracle database (or any software) is released? You immediately look for the “what’s new” document, right?
I believe that the “What’s new” document is very important because it informs you of new (or modified) features that is supposed to make your life easier and your applications more powerful.
Take advantage of “what’s new”. After all, you’re paying for these new features (I assume), so use them or lose them.
To that end, here is a list of “what’s new” links. They will take you straight to the corresponding section of the Oracle documentation:
What’s new in Oracle Database version:
What’s new in SQL in Oracle Database version:
What’s new in PL/SQL in Oracle Database version: