Re: Job interview questions

From: Tim Gorman <>
Date: Thu, 04 Jun 2015 12:34:35 -0600
Message-ID: <>

I'll take a whack here too...

I think the intent behind asking obscure technical questions is to initiate a conversation on a very specific technical topic. With luck, the seemingly trivial question can reveal not only that the candidate is fluent on the whole topic, but also something about how they relate to other people and how they might fit in.

For example, asking a question such as "/What is the common nickname for an 'inconsistent' backup?/" (answer: "/hot/" or "/online/" backup) can lead to several great follow-up questions about how backups are captured and why they're recoverable. For example, if they get that right, you can then ask if simply restoring an "inconsistent" backup is sufficient to open a database successfully, or whether additional steps are necessary (i.e. "/no/" and "/recovery rollforward with redo logs/" are good follow-up answers). If you have a suspicion that the candidate is snowing you, then you can ask whether datafiles are "locked" against writes while they're being backed up or not, and find out if they have some whopping misconceptions about how Oracle works.

Getting these answers correct or incorrect is not really the point; lots of good people get them wrong. In real life, people can google for these answers.

But how they interact with you during this conversation is very revealing. Whether they know this stuff or not. Whether they freeze up when faced with a complex problem, or whether they grow more engaged and animated at the challenge. Whether they actually get angry when confronted with their failure.

If they know their stuff and answer correctly, again it is illuminating. Some get cocky and rattle off the answer in an almost arrogant fashion. Some are undoubtedly arrogant about it. Some are just matter of fact and cool and collected. Maybe you want arrogant. Maybe you don't.

Of course, the follow-up questions can go another way, into personal experience and war stories. "/What is the scariest situation you've ever encountered?/" Every infrastructure person has been scared stiff at one point or another, and if they haven't, then they haven't done anything. It's not fair to ask someone about their failures during an interview, but I think it is quite kosher to ask someone about when they were most frightened.

So, an interview isn't merely a series of trivia questions to be scored, summarized, and averaged. No doubt scoring correct answers is useful, but there's much more. Good questions encourage the candidate to reveal something about their own characters.

On 6/4/15 12:02, Iggy Fernandez wrote:
> Dear TJ,
> I absolutely loved the blog post recommended by June and read every
> word of it.
> I remember the interview at which I could not answer the question "how
> do you enable block change tracking in a database?" (The answer is
> "alter database enable block change tracking,") I don't want to work
> for Yahoo any more.
> I remember the time when I could not get hired at Google because I
> could not solve a riddle.
> I don't want to work for Google any more.
> I remember the worst interview of my life when the hiring manager
> walked me to the door when I correctly answered a simple question
> about redo logs (he was wrong).
> I don't want to work for [let me protect the guilty] any more.
> Personally, I don't think the absence of particular technical skills
> matters that much. They can always be learned by a motivated learner.
> I would prefer a motivated learner rather than a really knowledgeable
> person with a bad attitude or who never got anything done.
> The person's work history and the opinions of his/her previous
> co-workers and managers is the information we need but we don't have
> it. Only some LinkedIn accolades like "his unique skill taking on
> abstract blue-sky corporate objectives and converts them into specific
> actionable goals".
> The company takes a big risk by hiring me (how can anybody really
> evaluate me in a few hours?) but the bigger risk is the one I take in
> joining a company. The question I want to ask (but never do) is "Who
> am I replacing? Why did they leave? What did they not like about the
> job? Can I call them?" Also, "Do you believe in work/life separation?"
> Also, "Do you ruthlessly lay of employees like [let me protect the
> guilty] in order to achieve the quarterly earnings target?" Also, "how
> crazy is database administration in your company; is it as wonderfully
> wonderfully (wonderfully) smooth as eBay and Intel or as crazy and
> terrible as [let me protect the guilty]." Also, "Do your team members
> go to NoCOUG conferences and, if not, why not?" Excuse my NoCOUG plug.
> I would hire a young person or experienced person and teach them all I
> know but companies don't like to do that. They do like to complain
> about the shortage of good DBAs though. I once hired a person with
> very little Oracle or DBA experience and asked him to work on
> certification. He completed certification (8i) in nine months and, 15
> years later, is still with the same company as a glorified Oracle
> architect.
> For every technical hard-to-answer question somebody asks me that I
> cannot answer (e.g. how do you fix wait event "X" on Exadata 12c
> Release 2), there is a technical harder-to-answer question that I can
> ask them that they can't answer. My favorite is "What is
> serializability of transactions. Does Oracle provide it?" (the answer
> is "No").
> with
> two additional links at the bottom.
> I have never met a DBA who could answer the question "what are the
> deliverables of the DBA role?" to my satisfaction. How likely is it
> that I will work on the deliverables if I cannot articulate them?
> Installing security patches is not a deliverable, but a task. I would
> hire a SQL Server DBA who could give me even a partial answer and was
> a quick learner.
> I have often been rejected for jobs because I was not competent enough
> _at that time_. I have achieved all those competencies by this time
> but, strangely enough, I no longer want those jobs any more. There are
> jobs out there that I want but they won't hire me because I am not
> competent enough _at this time_. C'est la vie.
> Just some random thoughts of course. Kindest regards and best of luck
> finding and retaining great people.
> Iggy.
> ------------------------------------------------------------------------
> Date: Thu, 4 Jun 2015 18:29:19 +0200
> Subject: Re: Job interview questions
> From:
> To:
> CC:
> Hi,
> an interesting post I recently read:
> Regards
> On Thu, Jun 4, 2015 at 5:50 PM, TJ Kiernan <
> <>> wrote:
> For those of you who have conducted job interviews, what sort of
> questions have you found to be effective in evaluating a
> candidateís skill level? Iíve started a list that consists of
> some Oracle trivia and some open-ended work habit/personality type
> questions.
> Incidentally, I know of a Oracle DBA job opening in Omaha, NE.
> Please contact me off-list if youíre interested in knowing more.
> Thanks,
> NPS.png
> *
> *T. J. Kiernan
> Lead Database Administrator*
> *National Pharmaceutical Services
> P.O. Box 407 Boys Town, NE 68010
> Direct: (402) 965-8800 extn. 1039
> Toll Free: (800) 546-5677 extn. 1039
> E-Mail: <>

Received on Thu Jun 04 2015 - 20:34:35 CEST

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