Oracle database unbreakable ?

Have received recently a copy of Oracle Unbreakable Linux?! from Technet.oracle.com
but i have a doubt regarding it unbreakable for there is a book titled "The Oracle Hacker's Handbook" written by David litchfield, that i've just bought it. You can read the excerpt of the book here.

My new assignment in one of the World's Local Bank :=)

My news tasks are mainly focused on ETL and the bank data analysis.