This is good. This is better than good. I consider myself a pretty good technical writer, but I've never been able to pull off this combination of nitpickingly complete technical detail, utterly clear tutorials, and friendly, readable prose.
If you're new to Delphi, you need to read this book. It covers important functional details that are not clearly described anywhere else.
If you're an experienced Delphi programmer, you need to read this book. It covers all the practical details you thought you already knew.
If you're a novice database programmer, you need to read this book. You can use it with the evaluation version of Delphi (download for free) to learn how client-server applications are supposed to work.
If you're an experienced database programmer, you need to read this book. It will show you what you're missing in your current development environment.
Never mind the "Delphi 3" in the title. There are details that are inconsistent with Delphi 5, but these problems are simply overwhelmed by the extreme clarity of the text.