Jonathan Gennick’s SQL Pocket Guide is a seamless guide any Database Admin or developer, expert or beginner alike, should have in their IT toolbox. I recall when I was in the university; I picked up a “learn SQL in 24 hours” book as a supplementary to our curriculum book. Had I had this pocket guide then, I would have most certainly struggled less. Most recently I been developing .Net applications to a Pervasive SQL Database, and even with years of Microsoft SQL Server experience, this reference book has been on my side.
SQL is a platform independent database language, this guide will provide guidance and examples for Oracle, DB2, SQL Server, MySQL and PostgreSQL. You can also download code sample for all the mentioned platforms. Moreover, the organization of the book will indicate platform specifics, for instance, Data types spans several pages to distinguish between the various database platforms.  The book is structured in alphabetical order by commands, this makes it easier for when you know you want to write a UNION but don’t remember the syntax, you’re sure to find it towards the end of the book. At times it may seem there are superfluous references to databases you don’t work with, nonetheless, it is a Pocket Book primarily for reference and I won’t hesitate in recommending it.