Database Developer: Must-Ask Interview Questions

Prepping to interview a candidate for your Database Developer position, but unsure of what questions to ask to ensure you’re finding someone who can bring that “extra something” to your company? We’ve got what you need. Use these sample questions to help you determine which candidate is more than merely skilled and experienced in the basics—someone who will bring the acumen that can help elevate your company and support its needs above and beyond the usual. Not only will that help make the interview process easier, it will also help you uncover the tech professionals who are deep-thinkers, high-performers, and all-around true standouts.


Question: Which databases do you have the most experience with, and have you worked with both cloud and physical databases?

Why you should ask: With so many different kinds of database infrastructures that meet different requirements and needs, it’s helpful to know which ones your database developer candidate is the most skilled at, and familiar with. But it’s not just about gaining further clarity on their experience—it’s about understanding their tech fluency, their ability to grasp and use more than one solution as needed, and the versatility of their training. Bonus points if they can tell you how many databases they’ve been able to work with at one time, as it can also tell you the size of company and scope of projects they’ve worked with in the past.

An answer you’d hear from a stand-out candidate: “For the most part, the vast majority of my experience is with Microsoft SQL Server, as that’s one of the more dominant databases throughout the industry, and the one that most of my previous employers have worked with. However, I also have experience with MongoDB, and I’m constantly learning about other options and advancements to ensure I can meet the needs of my clients or employers. As for working with databases that are physical or cloud based, I have experience with both. Like most database developers, I started working with physical databases, and have since learned how to work within hybrid or fully cloud-based databases as needed. Because so many are moving toward a completely cloud-based system, I’ve been working on getting certified in AWS so I can be prepared, and also help with migration if need be.”


Question: Can you tell us about the most challenging project you’ve worked on and how you overcame those challenges?

Why you should ask: As much as we would like it to be, tech isn’t foolproof—and even the best-laid plans and database developers can succumb to issues ranging from minor to disastrous. Not only will asking this question help you learn more about your Database Developer candidate’s capability to handle their workload and their process behind tackling projects, but you’ll also learn how they operate under pressure and handle projects that may go awry. If they’re able to share how they troubleshoot issues to your satisfaction, then you know you’ll have a solid team member who’s ready for anything.

An answer you’d hear from a stand-out candidate: “There was a company I was working with who struggled with expansion, and that translated into issues with our database performance. The more data we took in, the more we had issues with processing—and part of the issue was that we needed to add to our server databases, especially so we had back-ups in case of emergency. The challenge was creating a server database that offered strong performance without requiring constant monitoring, but also included assignment failover in case there was a node that failed during a task performance—that way we could transfer that task to another node automatically. After building out the server requirements, I was able to successfully migrate our data with limited issues and was able to help the company maintain performance across the servers without downtime.”


Question: What is your experience in handling data loss during a migration, and how have you handled it?

Why you should ask: When data is king, you want to ensure it’s protected and safe no matter what—but that’s not always guaranteed. And your potential Database Developer knows that more than anyone. While loss of data during migration isn’t necessarily ensured, it still happens to the best of us—and asking your candidate how they would handle this challenge will show you how they think on their feet and apply their tech know-how to save the company from certain data disasters, which is a key component of the job.

An answer you’d hear from a stand-out candidate: “While it’s a situation I work hard to avoid, unfortunately I’ve encountered it in the past and have had to work fast to address the issue. The first step is to determine whether the issue was associated with the migration, or if it was a singular problem—this helps me to figure out what stage of back-up I should source to use as our data restoration point. From there, I do my best to retrace my steps to ensure that I’m clear on what data needs to be migrated, creating a profile that shows the quality of the data we’re migrating so we’re not copying over anything that’s corrupt or unnecessary—and then cleansing data as needed. Being able to trace the issue back to its source can sometimes be the biggest challenge, but once I’ve figured that part out, it can set us up for a successful migration going forward.”


Question: How do you troubleshoot problems within a database?

Why you should ask: True, you’re asking a lot of questions about troubleshooting, but it’s an important part of interviewing for a new Database Developer because of the nature of the position—and the tech they’re managing. But the most important part of asking this question to candidates is how their answer reveals their problem-solving process, especially under pressure. It can also show you how they identify problems and create a strategy to solve them, and how they allocate resources in those instances.

An answer you’d hear from a stand-out candidate: “Because I’m so stringent about doing routine audits and constantly monitoring the databases I’m in charge of, I’m always looking for issues that are being reported, or problems that are being called out by others who have access to the database. Once I’m able to see what these issues are, I work to trace the problem back to its source by identifying what the symptoms of the issue are, how they’re affecting the user, and then addressing any potential causes behind the issue. Then I handle any fixes or repairs as needed, or outsource those fixes or repairs depending on how complex they are—but for the most part, I try to take care of things in-house, because this gives me a greater understanding of how our database operates and what I need to look out for in the future.”


Question: How would you ensure our databases are secure?

Why you should ask: No doubt about it—security is key throughout all aspects of the tech world, but when it comes to databases, you want to make sure all the Ts are crossed and the Is are dotted, so to speak. Your potential new Database Developer should know this as well, and should also know exactly how to protect your company from potential breaches or leaks. Asking this question will help you gauge that know-how, and also show you how strong their understanding is of current security concerns and solutions for the industry.

An answer you’d hear from a stand-out candidate: “Obviously having secure passwords is key, but beyond that I’d also want to make sure that we encrypt our database using strong encryption software that properly converts our data. As an added layer to this, I also recommend segmenting our database so each department or team who needs access to the database can have access only to the sectors they need, so that in the event of any kind of breach, it may only affect a certain subset and not the entire database. To that end, I’d also make sure the log-in isn’t easily found by search engines, but still accessible by employees who need it… and I’d also perform routine audits and monitor access so that we know who’s accessing our database and why, keeping an eye out for suspicious activity and making amendments to our security protocols as needed.”