Yes. No. Sort of. It's (not all that) complicated. This question hit my Twitter feed yesterday: When you enable all warnings, have you ever seen a "PLW-06006-- uncalled procedure removed" (lots of them), when they surely are called? Now that, I must admit, has to be a little bit concerning. You write code, you know it is going to, or should be, executed, and yet the PL/SQL compiler tells you it's been removed ? OK, OK, calm down. Everything is just fine. Here's the explanation: The optimizer performed an inlining optimization, so all the code for that procedure (or function) was moved to where it is invoked. The "original" nested or private subprogram that you wrote (and, don't worry, is still and always will be in the source code of your program unit) is, truth be told, never going to be called. So then the compiler removed it (did not include it in the compiled code - which is not PL/SQL code any longer). Let's take a loo...
For the last twenty years, I have managed to transform an obsession with PL/SQL into a paying job. How cool is that?