Funny or not. I used these questions interviewing people for the job (production dba that is). For fun at first... Honestly I had to 'lower down' my usual questions set, because we had really bad luck hiring anybody... either market was dry either what... beautiful resumes and in person uuuppss ... like if it was somebody's resume.
It was amazing how many people blow 80+% of these simple questions with nice resumes and tons of experience. I used the questions from this article for phone screenings. Whoever passed 'simple set' and then some additional questions or did not pass 'simple set' but had a fighting chance got in person interview and e-mail doc with 20+something questions and with unlimited resources to find an answer within 1-2 days. Some of my questions were set up to force an question to clarify... amazing, ... but so few actually asked a question. People who has scored low never asked a question. People who scored low/high on simple test had similar score on more advanced questions.
I had cases when people passed 80+% of questions (from this article and my own ones ), were brought in person and froze seeing a simple performance tuning task or something of that sort. Like they have never seen the tool set before or worked with a different database all together.
I've talked to people with questions range coverage from 50 to 80. An interesting observation, how many sql dba's with tons of experience do not know much or anything about the OS ms sql server lives in... I did not expect that to be honest.
There were comments here about people making mistakes during interview because they are people.
I can answer why I'm going to put pressure during interview period. In production when all hell breaks loose and that 'thing' gores down whoever that dba is ... they going to face the pressure. I need to know at least something about what they are likely to be doing, are they going to freeze, fight, hide or .
Have being on both sides of the interview 'table' as you have guessed. Interesting that during my practice I've seen actually only on case when there was a computer in the room and somebody wanted me to do anything not on paper.
When I was interviewing I found that most of the candidates did not expect to lee a laptop at all. Kind of like ... here he/she goes about such and such in his/her experience and it all sounds wonderful and solid, ok, here I turn the laptop and ask to show something he/she was talking about 2 sec ago. And we are done, nothing. Ok... and what I supposed to think about it, because the candidate was just describing how they were solving the same problem and how many times did they see it during their current job and did the same thing... like yesterday.
I can understand stress, but I want to see what the candidate is doing too...