SQLNS is an acronym for SQL Server Notification Services. Originally introduced as a “free addition” to SQL Server 2000, it is an integrated part of SQL Server 2005. SQLNS is a framework for a specific kind of application, a publish-subscribe notification application.


We did a chapter on SQLNS 2005 in our “First look at SQL Server 2005 for Developers” book, but came up about 400 pages short of doing it justice for the true afficianado. Recently I’d heard about a few SQLNS-specific books being released, one by an acquaintance of mine from the SQLNS development team, Shyam Pather. Devs don’t usually wrote books, and I just had to read this one. I just finished reading Shyam’s amazing “Microsoft SQL Server 2000 Notification Services” from Sams press. It’s just as good as I thought it would be.


I first met Shyam, Tete Mensa-Annan, and the other members of the SQLNS team when I spent a few days wallowing around in their knowledge of the product, in preparation for writing a DM course on the subject. They wanted to get developers and consultants up on the technology quickly. As far as I could determine, Shyam worked on the SQLNS engine itself, he and Phil Garrett and others spent a few hours with me a conference room, explaining the intriquicies of what they called “quantum theory”, that is, how the SQLNS scheduling and execution engine service works. Tete spent a few hours explaining how SMS protocol and aggregators work in detail. I was amazed at the depth and bredth of their knowledge of the subjects. I could hardly write/type/think fast enough to keep up.


Back to the book. It’s 600 pages of “SQLNS as a way of life”, from beginning to end. It explores setup (without any gratuitous screen shots of setup, THANK YOU), configuration, programming instances and applications, writing the processing configuration files, the subscription management application. There are chapters about custom event providers, formatters, and delivery protocol; there is an example of each. But of course, where this book shines most (is shine most the correct construct? hmmm…) is in the description of internals, tuning, and troubleshooting. That’s where it’s invaluable. I still remember going over “quantum theory” and all its permutations when I read that chapter.


If you use SQLNS as a notification application framework, it’s very easy to get a first instance working, but when your app gets popular and you need 10 more just like it immediately, working with SQLNS quickly becomes all-consuming, that’s what I meant by “SQLNS as a way of life”. If you’re looking to “check out” SQLNS or see if its “right” for your application that’s fine too, the preface even gets you quickly up to speed on the SQLNS lingo. I also remember Shyam writing to me a few times about the “its not a custom delivery channel, its a custom delivery protocol”. In any case, there’s *no way* you can be dissapointed with this book. I was so happy with it that I snagged a few copies to give away at the Guerilla SQL Server in Redmond. And Tete will be there to answer questions and help with SQLNS 2005 after the module/lab on it.