The book is short, thin but packs a massive punch. It covers everything about security and hacking you would want to know and seems (from skimming it) to do so quite comprehensively. This is difficult to achieve in a short book. There are some good reviews on Amazon.com, here is a quote from one by Anton Chuvakin
"Now, let me disclaim that I am not a big fan of thin books claiming to be "comprehensive". In fact, I was deeply suspicious while getting this "Hacknotes" thing. Was I up for a pleasant surprise!! This book does deliver what it promises. It walks a fine line of being both wide and deep, which I am still amazed about. From risk assessment methodologies to "find / -perm 0400" in just 200 pages is no small feat."
The book looks extremely useful as a hacking exam cram book - no exam needed!. Whilst it doesn't mention Oracle - from my skimming of it, it is certainly a book that a good DBA who is interested in security should consider for getting a good grounding in the security hardening / hacking techniques used.
A very useful book.