some questions for the post of DBA
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i went for the post of sql-server DBA.
i was asked questions out of this questions i was unable to answer 3 questions they are
1) how can u find out how many concurrent users can sql-server support.
2) how will u find out which queries are taking longer time to execute and how will u fix them.
3) what is the maximum row length in an sql-server200
if anybody knows the answer pls post it here
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*Sukhoi*[font="Arial Narrow"][/font]
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1st I don't know
2nd you can use profiler to log stored proc start and end times
3rd 8060 bytes
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverabilityWe walk in the dark places no others will enter
We stand on the bridge and no one may pass -
if there are 1000,s queries then do i need to check each query in a profiler, there is another dude
and he also asked me which hardware do u recomend as a DBA for sql-server2000 wht should i consider when i recomend a hardware
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*Sukhoi*[font="Arial Narrow"][/font]
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No, run profiler, save into SQL table, run queries. I had a very nice set of stored procs at my last job that. One would summarise profiler data and produce a top 10 worst performing.
One would give you detailed breakdown for 1 stored proc.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverabilityWe walk in the dark places no others will enter
We stand on the bridge and no one may pass -
u mean u had some stored procedures to trace worst performing queries, now u dont have them.
if we found out worst performing queries then how to work on that.
pls iam a DBA now
and 8060 bytes is very less for a row, wht if we have a text field in a table or an image field then
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*Sukhoi*[font="Arial Narrow"][/font]
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Text and image fields aren't stored in the row, all that's stored in the row is a 16 byte pointer. That's why a text/image field may store up to 2GB
How to fix worst performing queries. First, review the code, make sure that it is well-written, second, execute the stored procedure and review the execution plan. That will tell you if indexes need adding/changing.
Best thing there is experience. Run querys, look at the plan, change the query and see how the execution time and plan changes.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverabilityWe walk in the dark places no others will enter
We stand on the bridge and no one may pass -
Sukhoi, no offense in any way, we are all beginners from the beginng, so here's some advice to you.
Open up BOL (Books On Line) and start there everytime you wonder about something. There's lots of more info there than anyone can post here, especially to the very basic questions. Read, and read some more. Use BOL everyday, everytime something needs looking into. BOL is your best friend.
/Kenneth
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at this point i dont have bol, i know i can download it,its good to look at it ocassionaly, it has only information not answers to questions.
still some of my questions are un-answered
like which hardware should i recomend as a DBA. for sql-server2000
and how do i search for worst performing queries , is it only by the only way which GilaMonster has specified. or is there any other way
how can a DBA help developers in optimizing queries and or which way could developers be helped by a DBA
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*Sukhoi*[font="Arial Narrow"][/font]
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#1 SELECT SERVERPROPERTY('LicenseType'), SERVERPROPERTY('NumLicenses') should give you the License and Number of seats. SERVERPROPERTY also has other items of interest. I suggest you look it up.
#2 Use the SP:StmtCompleted in Profiler and run your SP. This will give you a duration column (If you don't see it add it to the columns returned). You can then use the output to find the slowest portions of your SP to work on first.
#3 was already answered.
BTW: Even though you don't have BOL on hand you can still use http://msdn.microsoft.com to search BOL indirectly through MSDN
for instance here is the page on ServerProperty.http://msdn.microsoft.com/library/default.asp?url=/library/en-us/tsqlref/ts_sa-ses_3mi1.asp
Gary Johnson
Microsoft Natural Language Group
DBA, Sr. DB EngineerThis posting is provided "AS IS" with no warranties, and confers no rights. The opinions expressed in this post are my own and may not reflect that of my employer.
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BOL is an essential source of information - not only occassionally, but on a daily basis. I urge you to begin using it - you won't regret it, I'm sure.
'Information' is what constitues an answer to a question.
Do not underestimate the value of BOL. By reading it and looking for the information about your questions, you will gain understanding of how things 'work' with SQL Server with time. The primary source of learning and understanding is to try and experiment.Hardware recommendations... Well, there is no universal recommendation - in order to do one, you would need to know such things as system requirements (eg OLTP vs DSS), budget, redundancy demands, recovery strategy etc etc. To be able to recommend hardware, you need to 'understand' hardware. (this is also covered in BOL to a great extent)
Performance related question... In BOL as well - profiler has much written about it.
How to help.. imo the best help is when DBA and developers are able to communicate, and understand each others 'worlds' so to speak. That's when the DBA can help developers the most. You need to understand the database stuff, and also the developers, so that you can convince them why they should change their 'evil ways' if they have some.
Bottom line is that much of the above is things that matures with time and gaining of understanding of one's own environment as well as others.
just my .02 anyway
/Kenneth
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As far as fixing the issues in 2 that is an issue of reviewing the execution plan, making index decisiion (which you can try the index tuning wizard), possibly rewriting the code and the can be times where even thou it is slow it cannot be helped.
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