Which Platform or Version?

In general, all of the discussions and examples in this book apply regardless of the machine and/or operating system you are using. In those few cases where a feature is in any way system-dependent, I note that in the text.

There are many versions of PL/SQL, and you may even find that you need to use multiple versions in your development work. Chapter 1, Introduction to PL/SQL describes in detail the many versions of PL/SQL and what you need to know about them; see Section 1.4, "PL/SQL Versions" in Chapter 1 in Chapter 1.