Instruct: Classify the given Amazon review as either positive or negative.
Query: Disappointed!

This black-white book had started very well with a clear explanation of what a database is.Unfortunately, from chapter 3 on, ill-explained notions are introduced and I got lost. I would like to have more connection with a practical case, it is not the case.Probably I am too stupid, or too new in the field of mySQL. A pity!