Each Oracle release has many differences.
All the changes you can read here. These are Developer related. We can refer at one place.
There are architectural differences.
- Another 5 neat 12c features for Oracle developers (iadvise.eu)
Here’s a simple command that you can use to change shells. It’s useful to work with multiple shells at a time.
Here is a resolution for SQL error -206. You will get an error of object is not valid. Here are possible reasons for this error. Also given solution for how to fix it.
How to use file descriptors in Unix is explained in this post. Unix supports three types. Here is an example that shows how it works.