Sunday, 7 February 2010

What I Learned At DDD8

First thing on Saturday morning my Twitterstream was full of sleepy geeks converging on Reading - yes, it was time once again for DDD at Microsoft. DDDs are free one-day conferences where all the content is from the UK Microsoft developer community - Microsoft speakers are not allowed to speak, although they usually come just to hang out. The community also decide the sessions that form the agenda by voting on submissions. I was lucky enough to speak at DDD7, but my session didn't make it into DDD8 (which was for the best as hardware failure meant I wouldn't have been able to do any demos). They're also a good networking event - a useful addition this year was to have people's Twitter names on their badges, which meant that if, like me, you follow a number of people you've never met, you could start to spot them and say hello. In fact, at one point I thought 'this is just a social thing with some technical content tacked on'!

Once I was at Microsoft and checked in, the first person I saw was Simon Harriyott, who I met for the first time the preceding Thursday at Barry Dorrans' leaving drinks. Of which more later. As I was getting my sausage sandwich and coffee, I also bumped into VBUG Chair Tim Leung and had a quick catch-up with him before it was time to head into the first session of the day...

Barry Carr - Contractual Obligations: Getting Up and Running With Code Contracts
I walked into this session and pleasingly got a seat next to virtualisation guru and all-round good guy Liam Westley, and behind Guy Smith-Ferrier and Gary Short. I picked this session as it sounded to be similar to some work that was done at my last company, and it proved to be a very interesting talk. The concept of code contracts stems from some work done by the not-yet-dead Bertrand Meyer, father of the Eiffel programming language. Contracts allow you to specify pre- and post-conditions on methods, functioning like Asserts. One of the most interesting demos was where Barry stepped through some code, which had both pre- and post-conditions declared at the start of a function followed by the body of the function; as Barry stepped through the code Visual Studio seemed to be jumping around the code instead of following the flow of code as written, due to the way that Code Contracts amends the IL that your .NET code outputs. However the highlight of this talk was probably when one delegate had the temerity to ask a question; his reward was a USB stick, however Barry threw it to him unintentionally hard and nearly took him out!

I followed this with ...
Neil Robbins - Hello Document Databases
Neil said up front that he's a new speaker and that this was his first DDD session, and proceeded to give a blinding talk on NoSQL and CouchDB. CouchDB (and its' GUI, Futon) are all based around a mantra of Relax, which several of us shouted out from the audience at certain points when Neil got tied up by some Linuk case-sensitivity issues :-) Neil's demos were done with CouchDB running on Ubuntu, which was a slight disappointment for me as it effectively means CouchDB is something I won't be able to run at work; Neil's comment is that the installer for CouchDB on Windows is only a beta. Which is a shame as CouchDB looks like exactly the kind of technology we could do with at work for asset management software - we've had several conversations recently around the Entity-Attribute-Value pattern, which seems to be the major problem that CouchDB solves.
Andy Gibson - Web Application Testing with Selenium
This was an introduction to using Selenium, which is something I need to look into further, however I have to confess to too much Twittering and not enough paying attention in this session, particularly after John Nolan tweeted that he needed some water (Memphis was by now getting seriously warm) and minutes later Craig Murphy brought some in for him!

Simon Sabin - Entity Framework - How to Stop Your DBA Having a Heart Attack
I went into this session intending to pick up some knowledge about the Entity Framework, as I basically don't have any and one of my colleagues is intending to use it on his next project.But for that, and for me really, it was the wrong session. I still took some points away from it though, the key one being that although the SQL produced by the Entity Framework can look like it won't perform well, you can spend a lot of time trying to optimise it yourself but get only comparable results. Another good takeaway concerned the DATE datatype in  SQL Server 2008 - traditionally when trying to restrict results to a single date, we've used a SQL BETWEEN clause with the bounds set to midnight and 23:59 for the date in question; in SQL 2008 we can cast DATETIME values to DATE and just search for rows where the date is the date in question.
Oh, and for my personal future reference it's pronounced Say-bin.

Barry Dorrans - A Developers Guide To Encryption
And on to the last session of the day, and Barry's last DDD presentation before leaving the UK to go and work for Microsoft in Redmond. I first met Barry back at DDD1 and I've seen him speak a few times since then, and he's always been good. However, I already knew that his session was going to have some disruption, having had a chat with Phil Winstanley about it at the aforementioned leaving drinks. And also having provided to Phil and Craig Murphy, the organisers, a video of a rather younger Barry when he was on The Crystal Maze. And we weren't disappointed, either by the session (very good) or the disruptions (very funny). Barry wasn't too fazed by the videos that kept appearing on the big screen (or by Jon Skeet and others pointing out both mistakes in his code and typos on his slides). It started with coverage of hashing (which is NOT encryption), and then proceeded to show symmetric and asymmetric (private/public key) encryption, X.509 certificate encryption and XML encryption. I think everyone will remember Barry's key point about symmetric encryption keys, which can become diluted the more they are used for: Barry's message is keys are like condoms, don't re-use them. The only thing I would have liked to see would have been for each level of encryption the kind of data you might protect with it e.g. the correct level of encryption for storing, say, credit card data. 

All in all another excellent day at Microsoft, I should like to say a big thank you and well done once again to the organisers, looking forward to DDD9!

No comments: