Interview question :critical issue faced by dba

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Interview question :critical issue faced by dba

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Jeff Moden SSC Guru Points: 1003870 More actions · Answer 1

vsamantha35 (7/3/2014)
Hi Experts,
I need some guidance on this.
Recently I have attended a job interview for sql server database administration and was asked to speak about one of the critical issue you have faced as a dba. I have explained of one of the issue I had faced in my environment. I spoke of database was suspect and I was able to recover from backups and I have explained the root cause of the issue stating that it was disk issue which caused the problem and told that we replaced the disk and we are able to restore the tlog backups + taillog backup and I was able to bring the database online.
I don't know why the interviewer wasn't impressed with the answer.
I want to know from exceptional dba's, normally when they ask such questions, what kind of answers or scenarios are they looking for ?
Appreciate your inputs.

I agree with what much of the folks have said on this thread. I'll add that it may have been a good indication that you probably didn't want to work at such a place after all. Interviewers who aren't impressed with something but don't ask followup questions during the interview to find out more tend to be idea-checkvalves not interested in the ways other people do things. At the very least, they should have asked more about what "we" meant and what your actual participation was.

For this particular problem, the interviewer was probably looking for a more esoteric answer about how the system automatically switched over to the clustered mirror, etc, yadda-yadda, and couldn't make himself understand that not everyone has such things and that you did a great job of recovering the database.

As for getting feedback from such an interview, forget about it and don't let it bug you. In most cases, it's just not going to happen unless you and the interviewer have a prior agreement that such post-interview dialog will occur. Just send them a card saying thanks for the time they spent on the interview and setup for the next interview... at a different company. 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

SQLBill SSC Guru Points: 51440 More actions · Answer 2

Being honest...I read the initial post and thought....ho hum...had a database problem and restored from the backup. Okay....that's good to know, but the interviewer said CRITICAL.

Restoring from a backup is something some places do daily. We are constantly restoring databases from prod to qa or dev (or qa to dev), or to our training server.

Now, were you on a time limit? Had you done some other checks to see if you could recover the suspect database without using a backup?

So, I can see the interviewer not being fully impressed. Now, if you had drives crash and need to be replaced, then reload SQL Server and recover your databases on a production server AND do it all in 4 hours. That might be impressive.

If you had trouble with a database server and your "pointy haired boss" told you he was an expert on clusters...and before you could stop him he deleted the Q drive (quorum drive with all the cluster stuff). Then you, with sysadmins, rebuilt the entire cluster and all databases in 3 days...that might be impressive.

But most DBAs can restore a database from backup in their sleep.

Bottom line...you told the interviewer something that was critical to you, but you didn't show what was critical about doing a basic database restore.

-SQLBill

Lynn Pettis SSC Guru Points: 442467 More actions · Answer 3

I don't know, looks like there was a drive failure on a production database, needed to replace a drive, restore the database to a point in time, using a tail log backup that they were able to take on failed database. Only thing that was missing from the narrative was how long they had to get the database back up and operational with minimal loss of data.

Jeff Moden SSC Guru Points: 1003870 More actions · Answer 4

I hate questions like that. Anyone that has interviewed for more than a couple of times can easily make something "glorious" up and get away with the lie because there's no way for the interviewer to verify a plausible but totally fictional story.

The other problem with such a question is that if you really are a good DBA, then you should not have had any "critical" problems to begin with. 😉

Shifting gears a bit... Considering how many people beg for urgent help on this and other forums because someone dropped a table and they don't have any backups, I'd have to say that the number of "DBAs" that have never done a restore (or backup, for that matter) far outweighs those that have.

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

Grant Fritchey SSC Guru Points: 398694 More actions · Answer 5

Jeff Moden (7/7/2014)
I hate questions like that. Anyone that has interviewed for more than a couple of times can easily make something "glorious" up and get away with the lie because there's no way for the interviewer to verify a plausible but totally fictional story.

I don't completely agree. I like to ask open-ended questions. I want to see people think through things in front of me and then explain to me what they're thinking through. Now, I don't think this question is sufficiently open-ended, but it's moving in the right direction.

The other problem with such a question is that if you really are a good DBA, then you should not have had any "critical" problems to begin with. 😉

Then I suck.

Shifting gears a bit... Considering how many people beg for urgent help on this and other forums because someone dropped a table and they don't have any backups, I'd have to say that the number of "DBAs" that have never done a restore (or backup, for that matter) far outweighs those that have.

DING DING DING! We have a winner on the internet today. Absolutely. I think it's a horror that there are so many databases out there with zero ability to recover from the slightest problem, let alone something catastrophic.

"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt

Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning

Jeff Moden SSC Guru Points: 1003870 More actions · Answer 6

Oh, I don't mind open ended questions for the very reasons you mean. I just hate THOSE types of open ended "explain to me how you've failed" questions. Heh... my answer is "It's my job to not fail. The biggest crisis I've had as a DBA is a logfile finally consuming all of the harddisk on a system they hadn't given me access to yet on the second day of a new job and the second biggest was when I determined that we were going to run out of harddisk space 6 months ahead of time. The first day was spent filling out paper work and peeing in a cup." 😉

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

SQLRNNR SSC Guru Points: 281334 More actions · Answer 7

Jeff Moden (7/8/2014)
The first day was spent filling out paper work and peeing in a cup." 😉

Was that also a failure?:w00t:

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw[/url]
Learn Extended Events

Grant Fritchey SSC Guru Points: 398694 More actions · Answer 8

SQLRNNR (7/8/2014)
Jeff Moden (7/8/2014)
The first day was spent filling out paper work and peeing in a cup." 😉
Was that also a failure?:w00t:

Depending on my mood and the attitude of the person receiving, that can be a partial failure, if you know what I mean.

"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt

Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning

Jeff Moden SSC Guru Points: 1003870 More actions · Answer 9

SQLRNNR (7/8/2014)
Jeff Moden (7/8/2014)
The first day was spent filling out paper work and peeing in a cup." 😉
Was that also a failure?:w00t:

Heh... no. I studied real hard on how to do it without getting my hands wet. 😀

--Jeff Moden

RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

Change is inevitable... Change for the better is not.

Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

SQLRNNR SSC Guru Points: 281334 More actions · Answer 10

Jeff Moden (7/8/2014)
SQLRNNR (7/8/2014)
Jeff Moden (7/8/2014)
The first day was spent filling out paper work and peeing in a cup." 😉
Was that also a failure?:w00t:
Heh... no. I studied real hard on how to do it without getting my hands wet. 😀

rofl

Jason...AKA CirqueDeSQLeil
_______________________________________________
I have given a name to my pain...MCM SQL Server, MVP
SQL RNNR
Posting Performance Based Questions - Gail Shaw[/url]
Learn Extended Events

AppSup_dba SSCrazy Points: 2215 More actions · Answer 11

This has been one of my favorite question. There are no right or wrong answers i expect. I just look for these points

- problem solving approach

- Ownership, candidates role in solving the problem

- attitude towards problem

- homework or knowledge gather regarding the issue

- what step were take to make sure problem doesnt happen again

- communication skills

Cheers