Voice of the DBA

Tag: software development

  • On Source Control

    A mention today from Jamie Thomson in his blog on source control. I left a comment, but it was long, so I thought I’d repost it here.

    My comment

    Thanks for the note, Jamie, and it’s interesting, but I don’t see any respondents that aren’t using VSC. I’m guessing many people don’t want to admit that.

    I use source control, sort of. I don’t have a lot of production code, mostly demo stuff, which doesn’t change so much as gets scrapped and restarted. However I am using Subversion (Turtle interface) with Red Gate’s SQL Source Control (of course).

    Why? Well, since I have a 1:1 with my boss today, I should mention Red Gate makes a fantastic product that I couldn’t do without. Actually I think I’m bound to use it since I work for Red gate, but even if I didn’t, it makes things easier.

    I built this habit at a startup, with Visual SourceSafe, and 6 months of browbeating developers to actually check out code from VSS, do a File | Open in Enterprise Manager (SQL 2k at the time), make changes, save the code, and check it back in. It can be done manually, and should, but there are tools like Red Gate’s products that make it easier.

    I know lots of people just edit code in SSMS/VS without controlling it, and that’s a mistake if you are trying to work in a team environment, and product quality software. I haven’t had to roll back often, but there are times we have needed to, and not having control was an issue.

    As an anecdote, I had a job once, waaaayyy back in the last century, using SQL 6.5. The developers had done a great job of using source control for all ASP, VB6, and SQL code. The problem was that they had checked out the code, saved it locally, copied it to another folder, and then checked it in. Then they might check back in the original script that was checked out. Or they might check the original back in and forget the modified version. Or they might not check anything in.

    We found 3, 4, even 7 copies of some stored procedures on various desktops and shared drives, and they had decided to encrypt all the code on the SQL Server. We were never quite sure what version was deployed where, and deployments of the "latest" versions from VSC broke functionality.

    We ended up decrypting all code, and reloading it into VCS, while removing all copies of local storage. It isn’t enough just to use source control or implement something; you need to understand what you are doing and do it consistently. Tools help here, so please use something.

    A Couple More Thoughts

    Source control is insurance. It’s risk reduction, but something that most people don’t understand or think they need. They may not. If you never have a server crash, or a hack of your data, then you don’t need backups. However most people wouldn’t want to run their systems, especially the ones they care about, without backups.

    It’s the same with source control. Use something to provide yourself with a fallback if you have issues.

    It’s not hard, there are lots of tools out there, and they make it easy to conform to some process. You can use SQL Source Control or SQL Connect from my company, or use something else, but integrate your database code with source control.

  • Pair Programming

    pair programming with cat
    I could probably handle some pair programming with this little one.

    I’ve never pair programmed, but I’m not sure I’d like it. As much as I like collaborating, I prefer alone time to work on problems, or think things through and experiment a bit on my own. I prefer brainstorming and discussion sessions to be limited in nature, with the chance to then go work on my own pieces along.

    However pair programming has been touted as a way to improve software quality by many people. It’s not as popular as some other methodologies, but it still exists out there. I ran across a programmer’s reflections on nine months of pair programming that made for a thought provoking read. He looks back at the experience and lists some pros and cons. Better code, more productivity, and lots of knowledge transfer were some of the positives, and would lead many managers to try and push developers into working in pairs.

    However there were downsides. As someone that speaks regularly, I think that the strain on my vocal chords would be hard if I had to speak constantly to someone else. The fact that the environment needs to be consistent for both people would also be a problems as I often find strong opinions from  developers in technology as to how they want an environment configured for their tasks. I know that watching someone else control a browser drives me a little crazy. I think I’d definitely need to have a separate machine for many tasks.

    As with anything, pair programming makes sense at times. I know that I’d like to have senior T-SQL coders work with junior ones when developing complex queries and explaining how and why they solve problems with certain techniques. Doing this in real time might slow down the senior person, but I think the evolution of one’s thoughts as they solve a problem is as important to learn as the inner workings of the actual code.

    The Voice of the DBA Podcasts

    We normally publish three versions of the podcast each day for you to enjoy. Today there is no podcast due to Steve being ill. Hope to have the podcasts return tomorrow.

  • Trade-offs

    scale
    There are always trade-offs when building software.

    I’ve always told my managers that building software is a trade off. We can do things cheaply, or we can do them quickly, but we can rarely do both. We can certainly fail in both ways, and many people do, but I usually see the need to trade time for money, or vice versa, when building software.

    I ran across a piece recently that was similar, though in it Allan Hirt says you can do things right, do them fast, or do them cheap. Allan talks about limited resources in working on projects. At some point time, budget, and staff resources are constrainted and you can’t expect stellar performance on extremely large workloads in a 24x7x365 environment. Something has to give, and one of those resources is going to let you down.

    I had always looked at people as a “money” cost, since they are paid for work, but there is another constraint to people that I hadn’t considered. Each individual in your company isn’t just a resource that’s exchangeable for others. Each individual has knowledge and skills that aren’t easily transferred to, or replaced by, other employees. In addition, each person has time constraints; they will only work so much in a given time period.

    Building powerful, efficient, effective systems, whether in software, infrastructure, or even in culture takes effort, time, and money. However if you do it well, it’s something you’re not only proud of, but something that pays for itself over and over.

    Steve Jones

    The Voice of the DBA Podcasts

    We publish three versions of the podcast each day for you to enjoy.

  • Rewrite the Coding Rules

    Cryptanalyses
    It’s becoming more important to code securely.

    Security is a problem in technology. Whether it’s technological misconfiguration, social engineering, or brute force attacks, we see a constant stream of headlines about security issues. The situation is not likely to change anytime soon as security isn’t seen as a priority by many companies. If that’s the case, then is there anything that can be done to improve security?

    Security expert Dan Kaminsky says that we need a fundamental change in the way we write code. By rewriting the way that code is developers, rewriting the rules, we can reduce the vulnerabilities in our applications. One theory is that our languages and the coding techniques used are making it entirely too easy for vulnerabilities to creep into code.

    It’s an interesting theory, especially these days when it seems so many of our applications are under attack. I suspect that we have lots of poor habits ingrained in many developers. People are loathe to change and they like to continue working in ways that have worked for them. However the world of security in software changes constantly. What might have made you a very effective and productive developer five years ago might make you a liability today.

    I believe that we need to somehow build new coding methods, but even more importantly I think people that provide sample code and framework need to do so in a way that showcases best practices and good habits from a security perspective. That includes presenters, who should never show security issues, even if it’s for the sake of simplicity. Raise the bar and your audience will come along with you.

    Steve Jones

    The Voice of the DBA Podcasts

    We publish three versions of the podcast each day for you to enjoy.