SQL is Insecure Part 2: Protect us from the idiots

On Christmas Eve I wrote a post titled SQL is Insecure in which I asserted that, because SQL has been systematically used incorrectly, that no one should use it. In this post I want to discuss why a complete ban of SQL is actually a good idea: while you personally are smart enough to stay away from the traps, it’s still you’re responsibility to prevent others from falling into those same traps.


In the original post, I referred to “junior developers” as a person who wants to “get shit done” in order to please management, sometimes introducing things like SQL injection vulnerabilities. The truth is tenure or experience have little to do with it. These developers are just idiots.

What makes an idiot developer? I know I’ve been an idiot developer in the past. I like to think I’m too experienced to make those mistakes these days, but honestly, I bet I would still make those same mistakes if you put enough pressure on me. So yeah, crazy amounts of management pressure to deliver results can also produce idiotic engineering decisions. If you’re a manager, I want to encourage you to create a culture of good work/life balance.

It’s not just current culture. At a previous company, I worked for a manager that actively helped me grow professionally. He was one of the few managers that I’ve had in my career that actually had my best interest in mind. It was a great environment. And then upper management fired him and replaced him with a VP willing to hire idiot developers to get shit done.

So, lesson learned: companies change, and they’re incentivized to change for the worse. Always assume that an idiot will be working on your code in a few years.

Other people point out that government contractors aren’t encouraged to spend time on quality. The spark that caused me to write the original post was caused by a poorly done government contract. Sure, there’s a lot of broken things about how government contracts are conducted, these need to be fixed, but the consequences of SQL injection are hurting real people, right now. Today governments are being manipulated, money is being stolen, identities are being compromised. We could make laws and require certifications and licenses to make software. All this would probably work, but not soon enough.

I’m a software engineer, not a congressman or a manager. I might not be able to make laws or mold company culture, but there are still things I can do to make the world around me a safer and better place.

Idiot Proof

What does the world look like through an idiot developer’s eyes? I know I’ve been there — exhausted, looking for the quickest and fastest way to get things done and deliver results. Of course I plan to come back and pay the technical debt, but if I’m completely honest with myself, that’s never going to happen.

It’s right there:

looking for the quickest and fastest way to get things done

To write idiot-proof code, make sure the quickest and fastest way to get things done is safe and secure. You might introduce an ORM to wrap your SQL database, but what happens when it doesn’t work? Remember, the idiot is looking for the quickest and fastest way to get things done. The go-to tool is mysql_query('SELECT * FROM users WHERE id = ' + user_id + ')'. Maybe the ORM isn’t even broken, it could be that the idiot developer just doesn’t want to take the time to understand how it works.

It’s not that SQL can’t be used securely, it’s that the most obvious way to use it is inherently insecure. Most of the literature teaching SQL demonstrates it being used in a way that’s vulnerable to SQL injection. Your cool ORM framework might be idiot-proof, but a true idiot will bypass the ORM.

Other Ways to Idiot-Proof

It doesn’t stop at SQL or security, here’s some other ways to isulate yourself from the damage caused by an idiot:

  • Don’t manually allocate memory — don’t use C, use a garbage collected langauge. It’s too easy to make a fatal mistake. You might be smart enough, but don’t trust that the next guy is.
  • Don’t roll your own crypto/web framework/database/etc. You might be smart enough to understand the complexity, but the next idiot is going to screw it up and cost your users.
  • Avoid synchronizing code for thead safety. You’re probably smart enough to deal with concurrency bugs and avoid leaked data, but the next exhausted engineer will mess it up. Use actors instead.

How else can you idiot-proof your code? What else can to do, as a software engineer, to make the world a safer and better place?