Instruct: Classify Amazon reviews into positive or negative sentiment
Query: SQL Server Basics

I work with SQL on a daily basis, mostly running queries. I needed a book to fill in all of the holes since I was self taught. This book is a great start at filling in the gaps. It covers everything from the different versions to understanding the design of full-text catalogs. There is also some good material on queries. Great book even if you are not going for a SQL cert.