Voice of the DBA

Author: way0utwest

  • Anatomy of a tSQLt test

    I’ve been doing some work on testing database code, and working with the tSQLt framework. I really like the framework more and more, and want to continue to use it. The whole idea of testing is a bit immature in database code, and perhaps software in general, but at least the software people are trying to move forward. At least in places.

    As I’ve been learning, and presenting on this, I’ve started to adopt and follow the simple pattern espoused by the tSQLt framework. It makes sense, and it provides what I think is a good format for unit test. The structure is:

    • Assemble
    • Act
    • Assert

    It’s simple, and it makes it easy to see how a test works.

    Assemble

    Declare variables and create tables you need. Insert data, initialize values and ensure that you have an expected environment on which to base your tests. I think this is especially important for database code tests.

    Act

    This is the place you call your code, or perform some action. Usually easy to do, but there are some thing that might be tough to set up.

    Assert

    This is where you assert, or declare something to be true. A value is equal to another. A result set looks like another. Something that you declare to be true, which could be some condition, like an error has occurred. If it’s true, the test passes. If not, it doesn’t.

    More to Learn

    There is lots more to learn, and I’m trying to do more. However I also need others to not only try to write tests, but evaluate how well they work and also publish some code. Explain to people what has worked, AND what hasn’t. Having that information out there, for a large variety of cases, will help others better test their code.

  • Why Would You Move?

    I was reading a thread on Quora about why SQL Server is chosen by companies, and another on StackOverflow about why Oracle is a good choice. As much as I sometimes joke about the Oracle RDBMS, I think it’s a solid platform, and certainly wouldn’t resist working with Oracle databases if the opportunity presented itself. I like working with technology and enjoy learning about how different platforms work. However I also know that if I started working with Oracle, I’d be much less efficient, and certainly quite slower, in producing work than with SQL Server.

    I’d also probably make a lot of relatively poor decisions about how to run the database instance.

    I’m sure I’d get better writing PL/SQL, but that would take time. And in any setting, that also means that I’d be costing my company money while I learned the tricks, best practices, and skills needed to produce a well tuned, efficient Oracle-based application. It’s really no different than the way I have seen many highly skilled Oracle developers and DBAs come to work with SQL Server and try to treat SQL Server as if it ran the same way as Oracle (<shudder>cursors</shudder>).

    That’s why when I hear about companies making a quick switch to a new platform or language, I question the move. Certainly there are domains of problems that Oracle might solve better than SQL Server. There are situations where MongoDB is better than an RDBMS or Java makes more sense than C++, but there should be strong, solid technical reason why it’s worth trying something new. Not because a manager wants to save some licensing fees or a developer wants to try something new.

    By all means, experiment, but do so in small ways. Try new technologies with limited investments, and if they work, increase the investment. However for large projects, stick to what your staff knows best. Their skills are often the limiting factor in producing well written software, and in almost every situation, their salaries will far outweigh any cost of software that you license.

    Steve Jones

     

    The Voice of the DBA Podcast

    Listen to the MP3 Audio ( 2.5MB) podcast or subscribe to the feed at iTunes and LibSyn. 

  • It’s about Perception

    This editorial was originally published on Dec 9, 2009. It is being re-run as Steve is on vacation.

    It’s not just the code. Sure the code’s important, but it’s not necessarily the most important thing. It’s more than just the way something works, even if the code is written correctly and performs all the right calculations. That matters, to various degrees in different applications, but it isn’t the most important thing. The important thing is the way the application gets used, and the way the users feel about it. In other words, the perception of the application.

    The perception of all of our systems and the services we deliver is what really counts. I heard someone recently paraphrase a well known saying. I don’t remember it exactly, but it was something like “People never remember the quality code we deliver, but they never forget the lack of quality in our code.”

    That’s true, no matter what we deliver. Our users don’t remember the 500 days our database server ran without an issue; they remember the day it was down. They remember when our application rollout broke something or made them work more. And they definitely remember when the application is slow or doesn’t help them in their jobs.

    As an IT group, even as technologists in general, we have to  take this into consideration when we design and build solutions. Building great software doesn’t just mean meeting the specifications we were given to  the letter, or duplicating the functionality that we think is being performed or we think is needed.

    We need to make sure that our systems work with the user, that help the user and make their jobs easier. It has to provide some tangible benefits to the end user or they just don’t perceive it as being useful to them.

    I’ve rolled out applications before that had cool, new features that hadn’t existed before, or we had incorporated new functionality they had requested. But for some reason it didn’t work well, or smoothly, or the user didn’t understand how to use the system. The perception was that the application was a failure.

    None of us wants to be in that situation. We don’t want our work to go unappreciated. To do that we need to take the users’ perception into account when we’re designing and building software. We need lots of feedback as we go along and make sure we’re building the application the users actually want.

    Steve Jones

     

  • What will you see at SQL in the City

    London, Oct 24, 2014

    Seattle, Nov 3, 2014

    Come join us.