This is a defining book on the Oracle database for any developer or DBA who works with Oracle-driven database applications. Tom has a simple philosophy: you can treat Oracle as a black box and just stick data into it or you can understand how it works and exploit it as a powerful computing environment. If you choose the latter, then you will find that there are few information management problems that you cannot solve quickly and elegantly.
If you're doing database application development in the Oracle environment, you're going to have to know PL/SQL, the company's extended query and update language. If you want your programs to exploit the special capabilities of Oracle software, you'll need to know the language well. That's where the third edition of Oracle PL/SQL Programming comes into play.