"Data and Reality" by William Kent was recommended to me as an excellent book. However, if you read this Amazon page very, very closely, you will see that this "third edition" is actually "revised" by Steve Hoberman. This "third edition" actually differs substantially from the original.
In this case it means Steve Hoberman has added inessential summaries to each chapter, an excess of explanation where none is required, and cartoons. Slightly more deviously, he has referenced his own previous book in a footnote, and then slipped that into the original bibliography alongside the books referenced by Kent's original edition.
That would all be just mildly annoying, but what is worse is that he has "removed several sections of the book that are less relevant today than in 1978". This includes at least three whole chapters and I don't know how much else from within the chapters. He has done this even though, in his preface to the second edition (published in 2000), William Kent explicitly states: "A new revised edition would miss the point of the book. Many texts and reference works are available to keep you on the leading edge of data processing technology. That's not what this book is about."
Essentially, this is not the book you are looking for. The actual book is out of print, but was published by AuthorHouse which has recently been acquired by Penguin. I have emailed them to suggest they bring out the second edition again. I suggest you do the same, and then try and get it out of the library or borrow it from a friend in the meantime.