Re: Oracle DBA Interview Questions
Date: Mon, 14 Mar 2016 16:57:34 +0000
Message-ID: <CAPCNhx2y6t1PPYLRTXZXT7Cta4sWfK-MR4uB-V8+P9=1ZGW=yw_at_mail.gmail.com>
My thoughts Entirely. A practical test beats any certifications or memory tests.
On 14 March 2016 at 16:42, Mohammed Bhatti <mohammed.bhatti1_at_gmail.com> wrote:
> Excellent post, Robert! Exactly my thoughts and this is how I've
> approached interviewing candidates (except for sitting them down at a
> terminal).
>
> My own experience with Oracle docs for some of the IDAM stuff in
> particular, is that between 11.x.x.x and 11.x.x.y the documentation can be
> vary greatly. It gets very frustrating. Pretty hard for any candidate to
> keep up with that rate of change.
>
> --
> mohammed
>
> On Mon, Mar 14, 2016 at 12:31 PM, Robert Freeman <
> rfreeman_at_businessolver.com> wrote:
>
>> *Respectfully, I find the notion of DBA interview questions along these
>> lines tedious, at best and not a realistic measure of a DBA’s value, worth
>> or knowledge.* Such questions open way to many psychological issues –
>> stress, fear, pressures for many people. These kinds of questions that are
>> not a good measure of a DBA’s ability to actually do the job. Sitting and
>> answering questions under stress is nothing like recovering a database
>> under pressure. At least, that’s true for me. I worked with Exadata for
>> five years. Start asking me questions in this manner, I’m pretty sure I’d
>> sound like I could barely spell Exadata let alone manage it. Yet – I assure
>> you – if that thing craters – you probably want me fixing it. I know more
>> than a few customers certainly did when that was my focus.
>>
>>
>>
>> *Who the devil is possibly going to remember every detail on a product
>> where the documentation could easily reach the depths of the Marianas
>> Trench?* Then, with each question missed, factor in the “Oh blast, I
>> just screwed up” count going up and the likelihood of finding the answer to
>> the next question in the bright lights of an interview just go way down,
>> and down and down. This is not how one measures the worth of the DBA, nor
>> his/her experience – at least that’s my POV.
>>
>>
>>
>> For consultants who’s every next assignment is nothing like the last
>> assignment – so what if they spent the last 12 months working with
>> encryption – if they have spent the next 6-months working with some other
>> gnarly feature, the cobwebs of encryption are well beyond easy and instant
>> recall. If you have photographic memory – my hats off to you – I don’t. *I
>> remember concepts, architecture and basic how-to’s… the details change so
>> quickly, with each version in many cases, that there is little value to
>> stuffing them in my head anyway. *
>>
>>
>>
>> What do I find the most effective way to gauge a DBA’s skill? I look at
>> their resume, sit them at a computer and ask them to find me an answer to a
>> problem that is relevant but that they have never faced (or they faced long
>> ago and could not remember to save their life). *Let me see their basic
>> knowledge and research skills in action. Let me see how they are going to
>> GET the relevant answers to a problem that they have never faced, under
>> some due pressure. How intuitive are they at getting to the answer? That’s
>> what I want to see. How creative are they, yet how structured are they?
>> That’s what I find important. *
>>
>>
>>
>> Then – let’s have an open book practical exercise. Create a database for
>> me – using an OS you are familiar with, and without using the DBCA. Have
>> not done it in a while – great, here are is the documentation – here is a
>> list of physical disks all ready to go and here are the tablespaces, sizes
>> and related schemas – no GO! Give them a reasonable amount of time to
>> complete the task and measure…
>>
>>
>>
>> I think that the trough of interview is a legacy we can do without….
>>
>>
>>
>> My opinion, of course…. I’ve been wrong before, I’ll be wrong again..
>>
>>
>>
>> Robert
>>
>>
>>
>>
>>
>>
>>
>> *From:* oracle-l-bounce_at_freelists.org [mailto:
>> oracle-l-bounce_at_freelists.org] *On Behalf Of *Anton
>> *Sent:* Monday, March 14, 2016 4:54 AM
>> *To:* oracle-l_at_freelists.org
>> *Subject:* Re: Oracle DBA Interview Questions
>>
>>
>>
>> hello =) best question in my interview was: when selects without any
>> funtions can do redo ?
>>
>> On 03/08/2016 02:56 PM, rob_at_oraclewizard.com wrote:
>>
>> I've put togehter some questions for Oracle DBA's; however one of my
>> co-workers say the questions are a bit tough. Said "we don't want to scare
>> a potential employee." Can y'all comment, are these questions too hard?
>> Should I include more Backup and Recovery? What are your thoughts? -Rob
>>
>>
>>
>> 1. Make a column not null, but you have null values in the column.
>> How would you approach the problem?
>>
>> 2. How would you change the encryption algorithm on a tablespace.
>>
>> 3. Can you rekey (rotate keys) for encrypted tablespaces?
>>
>> 4. What process would you use to encrypt data in an existing
>> tablespace?
>>
>> 5. How to you rekey change the encryption algorithm on an encrypted
>> column?
>>
>> a. Alter table <table name> rekey using ‘<encryption algorithm>’;
>>
>> 6. A junior DBA deleted some archive logs prior to them being
>> applied to the standby database. How do you get the standby database
>> resynced?
>>
>> 7. You have encrypted a set of columns, there are existing indexes
>> on those columns. When you encrypted the columns, did the index get
>> encrypted?
>>
>> 8. You ran an datapump backup of encrypted data, you did not
>> specify encryption in the datapump command line, is the datapump file
>> encrypted?
>>
>> 9. In rman, you have executed CONFIGURE ENCRYPTION FOR DATABASE ON;
>> What encryption algorithm will Oracle use?
>>
>> a. select algoritm_name, is_default from
>> V$RMAN_ENCRYPTION_ALGORITHMS;
>>
>> 10. How do you find out what users still have the default password?
>>
>> a. dba_users_with_defpwd
>>
>>
>>
>>
>> ===================================
>>
>> Robert P. Lockard Oracle ACE President Oraclewizard.com, Inc.
>> "When given the choice between two evils, I always take the one I have
>> not tried." Mae West
>> (cell) 571.276.4790
>> (office) 410.766.6960
>> (fax) 410.766.0332
>> twitter _at_navonpilot
>> youtube https://www.youtube.com/user/n4281k
>> blog: http://www.oraclewizard.com
>>
>>
>>
>
>
-- Howard A. Latham -- http://www.freelists.org/webpage/oracle-lReceived on Mon Mar 14 2016 - 17:57:34 CET