When I open Oracle documentation to look for something, people usually raise their eyebrows (almost as they do when I open sqlplus). Most of them simply say: “What do you need the documentation for? Just open google and search”. Even though googling stuff usually works, I actually like the documentation (in some aspects at least).
The documentation contains almost EVERYTHING, even the most experienced and senior DBAs I’ve met didn’t know some behaviors that were documented. But because it has everything, it is also huge, so people sometimes get lost and simply prefer to google. But when you know how to look for stuff and where to find what you need, it’s not that difficult.
I should be clear that bugs, dynamic information (such as patches), and other knowledge base stuff is not part of the documentation. This is part of My Oracle Support (MOS) and requires a support contract. Other stuff, like how things in the database work, syntax, etc. can be found in the documentation in great detail.
When I work with the documentation, I usually go directly to the correct book and search the topic I’m interested in. For that, I go to the list of books (this is the one for 12.2 for example: https://docs.oracle.com/database/122/nav/portal_booklist.htm) and start there.
There are generally 3 types of books:
Concepts – in concept books you’ll find information about architecture of features, how things work, and more. For example, if you wish to understand the memory structure of Oracle, you will be able to find it in a book called “Concepts” which contains all the basic database information. Understanding how Data Guard works will appear in the “Data Guard Concepts and Administration” book and so on.
Guide or Administration – guide or administration books are more practical and more thorough books. They explain how to manage a feature or component of the database and explain some more internal structure and behavior. For example, the “Performance Tuning Guide” and the “SQL Tuning Guide” books contain a lot of information about the optimizer while the “Concepts” book explains what the optimizer is in a more basic way.
Reference – these books contain mainly command lists, command syntax, internal views and parameters. So the “Backup and Recovery User’s Guide” contains information about manual backups, hot and cold backups, archive mode and more. The “Backup and Recovery Reference” on the other hand contains all of the RMAN commands and relevant views.
Here are several books that I find very useful:
Reference – all data dictionary views and initialization parameters
SQL Language Reference – full SQL syntax
PL/SQL Packages and Types Reference – list of all built-on packages
New Features Guide – list all the new features of the current release
Performance Tuning Guide – lots of information about database tuning
Administrator’s Guide – if you wish to learn more about managing Oracle databases, this is the book
Next time, when you need something about Oracle, try to look for the right book search for the right chapter and read. Let me know if you learned something new.