Apr 20
Last time I was visiting our client the person showed me one process which was in suspended status for a long time. Using Adam’s great script(http://sqlblog.com/blogs/adam_machanic/archive/2009/03/30/who-is-active-v8-40-now-with-delta-power.aspx) I identified the SELECT statement which had ASYNC_NETWORK_IO wait type. MS said that this type occurs on network writes when the task is blocked behind the network and we need to verify that the client is processing data from SQL Server. The problem was that SELECT statement retrievs more than 50.000 rows , then the application manipulates (FOR ..NEXT loop) with that data and finally only 200 rows that a client had seen at the end. Well,thanks to SQL Server 2005 we changed the statement to accept a parameter for TOP clause and this wait type has gone. We have not seen a great improvment of the application as we did not expect it but it is another way to identify poor written queries.
Apr 18
Packt books have published Moodle Course Conversion: Beginner’s Guide by Ian Wild. This book promises to help teachers and trainers get “existing teaching material online quickly and easily”.
Getting your teaching material online quickly and easily depends on what material you want to put online, and how much of it you have. But you can certainly use Moodle Course Conversion to make the process quicker and easier.
Moodle Course Conversion is written in plain English. It’s laid out simply, and takes you through what you need to know on a step-by-step basis. It doesn’t get over-excited about the bells and whistles. It gets stuck in right at the start with what you need to know about Moodle and what you need to do to get your course online.
Chapter 1 covers the basics – Moodle history, logging on, editing your profile, deciding your role, and moodle themes.
From Chapter 2, you’re creating your courses. You learn about course structure and format, enrolling students and assigning teaching roles.
Chapter 3 focuses on adding documents and handouts, while chapter 4 deals with including multimedia content.
There’s lots more – with advice and practical tutorials on everything from how to communicate effectively online to setting and marking assignments.
The book is NOT aimed at techies who are setting Moodle up from scratch. It’s for teachers, trainers and lecturers who want to (or are being forced to) convert existing materials for Moodle.
Best way to get a handle on whether or not you like this book’s style is to read over the sample chapter pdf you can download from here: http://www.packtpub.com/files/moodle-course-conversion-beginner-guide-sample-chapter-5-moodle-makeover.pdf
You can also learn more about the book here: http://www.packtpub.com/moodle-course-conversion/book. Packt have other Moodle books – I can’t vouch for them, but you can visit http://www.packtpub.com/moodle-books to check them out for yourself.
Apr 16
Invoking services within the Intranet was in the design of Azure from the start. The .Net Services Bus of Azure allows local services to be called from the cloud.
A connection is setup from within the corporate firewall to the Azure servers in the cloud. This bidirectional connection is used to invoke services on the Intranet. The Services Bus is much more advanced than the Secure Data Connector from Google.
Azure is not limited to .Net, there are also Ruby and Java SDK for .Net Services available! To learn a bit, I downloaded and installed the Java chat sample. Encountered the error “The subscription cannot be created” during my first experiments. But waiting a while resolved the issue: probably the service didn’t unregister correctly during my first runs and the service bus needs to detect that the service was no longer present.
In the Chat example, client and service are running in the same application (multi-threaded). No need to deploy the service implementation in an application server. Also nice to see how the JAX-WS API is leveraged to create the service.
Connecting from Azure to Amazon (or the other way around) should be trivial. But integrating Azure with AppEngine (or Force.com) is a different story. Both cloud have there own version and solution for integration and interoperability. A ESB hosted in the cloud or behind the corporate firewall will bring that interoprability.
