I’ve been playing about with the ACCESSIBLE BY clause to create PL/SQL white lists in Oracle 12c. Here’s the article I wrote about it.
There seem to be some discrepancies in the documentation*, which I’ve highlighted in the article. Not sure if they are documentation errors, functionality that has been pulled and will reappear in 12cR2, or just misunderstandings on my part.
* I’ve posted comments on the docs, so if they are documentation errors they may get fixed.