Learning how to look things up in the documentation is time well spent investing in your career. To that end, you should drop everything else you are doing and do the following:
Go to tahiti.oracle.com.
Drill down to your product and version.
<b><i><u>BOOKMARK THAT LOCATION</u></i></b>
Spend a few minutes just getting familiar with what is available here. Take special note of the "books" and "search" tabs. Under the "books" tab (for 10.x) or the "Master Book List" link (for 11.x) you will find the complete documentation library.
Spend a few minutes just getting familiar with what <b><i><u>kind</u></i></b> of documentation is available there by simply browsing the titles under the "Books" tab.
Open the Reference Manual and spend a few minutes looking through the table of contents to get familiar with what <b><i><u>kind</u></i></b> of information is available there.
Do the same with the SQL Reference Manual.
Do the same with the Utilities manual.
You don't have to read the above in depth. They are <b><i><u>reference</b></i></u> manuals. Just get familiar with <b><i><u>what</b></i></u> is there to <b><i><u>be</b></i></u> referenced. Ninety percent of the questions asked on this forum can be answered in less than 5 minutes by simply searching one of the above manuals.
Then set yourself a plan to dig deeper.
- Read a chapter a day from the Concepts Manual.
- Take a look in your alert log. One of the first things listed at startup is the initialization parms with non-default values. Read up on each one of them (listed in your alert log) in the Reference Manual.
- Take a look at your listener.ora, tnsnames.ora, and sqlnet.ora files. Go to the Network Administrators manual and read up on everything you see in those files.
- When you have finished reading the Concepts Manual, do it again.
Give a man a fish and he eats for a day. Teach a man to fish and he eats for a lifetime.