There's very little useful information in here beyond what you'll find in Celko's SQL for Smarties book, which is a good reference, albeit full of errors. What's especially disappointing to me is that several sections from that book were moved into this new volume, but only lightly edited, if at all, thereby perpetuating many typos and technical errors from several editions ago. Technical books really need better editing if they're going to be good teaching tools, otherwise they just wind up misleading and frustrating the reader. In this case, I feel like I bought a bunch of outtakes and remixes from an artist whose recording contract demanded additional albums when only the first was truly inspired.