Stephen's first law of diagnosing problems in production: try to replicate in test. (Assumptions: you have a test environment, you use it regularly, and it is reasonably close to production). Sometimes you just can't replicate the problem – for instance, it might be due to an oddity in a customer data file that you're not allowed to run outside of production. In those cases, see if you can use a proxy. For instance, try copying the file and masking the sensitive data, then running it in the test environment (of course, the masking process might cover up the error that is causing all the problems).

Production needs to stay clean, and as developers we need to keep our hands out of it as much as possible. This is particularly true in a highly secure environment with strong separation of duties, wherein you might have to drag a sys admin into the picture just to get to obscure log files, for instance. Replicate the issue, solve it, document it, and make sure everyone else in the company is able to share in the lessons learned.

I wonder how many others didn't think to scroll down further on the Pex download page, and find this link? Visual Studio 2010 Moles - Isolation Framework for .NET. Moles is available for free, while the full Pex environment requires MSDN.

Once again I've learned the hard way that it pays to read the release notes. After installing Pex v0.91.x, suddenly I was having trouble running my tests in a particular solution. It has been driving me nuts - Visual Studio was throwing "object reference not set to an instance of an object" errors every time I tried to run tests, and the Test View was refusing to load any test names.

Finally, I noticed that I had a few tests that were still instrumented with HostType "pex" instead of "moles". I changed these around, and still got the error. Closed Visual Studio, restarted, and voìla, the tests can run, and Test View is populated again.

Pex and Moles - Release Notes

Can someone please tell me why Visual Studio 2010 no longer has the "Promote Local Variable to Parameter" refactoring? I use this every day. Thankfully CodeRushXpress has it, but the current version is a bit unstable, causing VS2010 to crash periodically.

I've been using AccuRev, including AccuBridge integration in Visual Studio, for close on two years now. And I like it. I don't know anything about the licensing fees, but for the enterprise that is interested in spending some money, it is certainly a good option. So, for anyone considering using AccuRev for source code control, and who happens to stumble across this site, here are a few points to consider:

I am using the latest edition of Service Factory - Modeling Edition (VS2008). I've created a number of FaultContracts in my DataContract model, and utilized them in my ServiceContract model. The generated code for the ServiceContract does not include the namespace or action for the FaultContract, i.e.

One should work hard to avoid Cursors in T-SQL – for instance, by using recursive common table expressions &ndsh; but when you need to call a separate stored procedure in a loop, you're stuck with them. I recently came across an excellent guide to the subject, Performance Tuning SQL Server Cursors, which includes the following enlightening piece of advice:

If you have no choice but to use a server-side cursor in your application, try to use a FORWARD-ONLY or FAST-FORWARD, READ-ONLY cursor. When working with unidirectional, read-only data, use the FAST_FORWARD option instead of the FORWARD_ONLY option, as it has some internal performance optimizations to speed performance. This type of cursor produces the least amount of overhead on SQL Server. If you are unable to use a fast-forward cursor, then try the following cursors in this order, until you find one that meets your needs. They are listed in the order of their performance characteristics, from fastest to slowest: dynamic, static, and keyset.

Every cursor I’ve ever written would have benefited from this.

A few weeks ago I stumbled upon a tool called Pex from the Microsoft Research Labs: "Pex finds interesting input-output values of your methods, which you can save as a small test suite with high code coverage." Not having much time to spend exploring it, I was fortunate to have time to attend a Twin Cities Developers Guild meeting tonight and hear a talk on on how to use the tool, which now has me jump started. First a few highlights of what I learned (without cribbing too much from Jason Bock's presentation), and then sample results from the method in my last post.