You can think of this as a set of case studies involving different uses of dB2. It is not about low level instances of how you query or modify your dB2 data, unlike several other books in this IBM Press/Addison-Wesley series. This book builds upon those, by assuming you are already well versed in dB2 itself.
Each chapter is quite internally coherent, and most can be considered case studies. But between chapters, as you might expect, there is only a minor narrative thread. Only one chapter really delves into actual code description (on CRM email), and it is written in java. The other chapters give higher level examples of how you might plug different products together, some of which you might have to develop, rather than buy. The common theme, of course, is how they all sit atop a dB2 instance.
In fact, the discussion is well written enough, and general enough, that you might be able to swap out dB2 and plug in a competitor's database. Sure, there are dB2 specific traits mentioned throughout. But if you have the ability and the commitment to develop a project above dB2, in a similar way to those described in the chapters, then you surely are able to make the necessary changes if you use another database.
It is a tribute to the authors' skills that you can contemplate this. Though, given that they are at IBM, I doubt that they would regard this with equanimity.