In my role as a consultant, it’s rare that I go on an interview anymore, though I occasionally get interviewed by a client, or interview potential DBAs for clients as part of my role. There are a number of these lists on the internet, but many of them are old and focus on trivia questions (there won’t be any questions on what’s clustered versus nonclustered index, but if you are interviewing for a senior role, you should know that anyway. I also like to focus on open ended questions, to gauge the depth of knowledge of the person I’m interviewing.
I will say that when hiring on the database engineer (i.e., development) side, the questions I love best aren’t trick questions; they’re experiential questions. For example, “Here is a common type of problem we need to solve. What would you do in this scenario?” And then we can dive in. As a quick example of one, “You’ve just taken over ownership of a database where most of the clustered index keys are uniqueidentifiers. Would you consider GUIDs a good clustered index candidate?” Then we can talk about yes or no, what makes for a good clustered index, and how you might go about changing it. Oh, and I’ll admit that my thought on this question has changed since Jeff Moden’s outstanding presentation on the topic.