I've never bought a 'Guide for Dummies' before and all the prejudices I had about them are turning out to be true.
This book's style is totally inappropriate for its audience.
Let me explain. If I bought a Dummies Guide to, say, Shakespeare or Windows Vista then I could forgive the author if it was written in a jokey or chatty style. These are subjects that attract dilettantes, readers who may want a more relaxed introduction to their chosen topic. But no one is going to want to read a book about Data Warehousing unless they are already an IT professional. Furthermore, when said professional (me in this case) picks up this book he/she isn't looking to be entertained - this isn't pleasure reading - they're looking to learn the facts as quickly and painlessly as possible. Long introductions and cringe making jokes just get in the way of this.
I'll give a 'for instance'. The author states that a data warehouse doesn't need to be large (terabytes of data and scores of tables, etc). Simple enough. He then decides to emphasise this point by paraphrasing the conversation from the film Crocodile Dundee where the hero whips out his knife and says to the mugger 'That's not a knife, this is a knife' (substite 'data warehouse' for 'knife' in the previous sentence). Why? Does the author think I'll be rolling around on the floor laughing, saying 'Gee, I only wish learning could be this much fun all the time'? Seriously, this dross takes up half a page.
The back cover proclaims that this is a plain English guide to Data warehousing. The publishers obviously don't understand the differnce between 'cheesy English' and 'plain English'. I wouldn't say this book is factually incorrect in anyway, it's just very inaccessible. It should be no bigger than an O'Reilly pocket guide, instead it is 300 pages of chat and padding.