February 19, 2012 at 7:46 am
Thanks for the question
Jason...AKA CirqueDeSQLeil
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February 19, 2012 at 4:35 pm
Hmm from the cited support link
Hash recursion and hash bailout cause reduced performance in your server. To eliminate or reduce the frequency of hash recursion and bailouts, do one of the following:
Make sure that statistics exist on the columns that are being joined or grouped.
If statistics exist on the columns, update them.
Use a different type of join. For example, use a MERGE or LOOP join instead, if appropriate.
Increase available memory on the computer. Hash recursion or bailout occurs when there is not enough memory to process queries in place and they need to spill to disk.
Hmmm seems one of the supposed correct answers is missing from the supporting document
Oh Well
February 19, 2012 at 8:40 pm
Oh well I thought the last option was increase memory in the server. Where as this found in the link provided by you.:w00t: But the option of constraint is not found. Can you give more explantion on that. Thanks.
---- Babu
February 19, 2012 at 11:21 pm
Hi,
I agree with the previous two posters. The webpage referenced clearly states that the 4th option should be "Increase available memory on the computer".
It seems that the correct answer to this is incorrectly given as wrong.
Cheers.
February 19, 2012 at 11:48 pm
The Increase Available Memory option is listed explicitly in the documentation, as other have already mentioned. Nowhere is something said about the constraint option and if it was a correct answer, then All of the above should have been the only correct answer.
Need an answer? No, you need a question
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February 20, 2012 at 12:43 am
The trouble with this question is that adding an index on the the columns being joined in one of the tables (whether or not it's a unique index) can only reduce hash bailouts by persuading the optimiser to use a merge join (or, if the tables concered are a large one which gets the index and a small one, a nested loop join) instead of a hash join in some of the cases where bailouts occurred. So in reality that is already covered by one of the other options (use a different sort of join if appropriate), so it's probably unreasonable to include the add a unique index option as part of the correct answer if only 4 options can be chosen, while the add extra store option most certainly ought to be part of the correct answer.
Besides, it's a bit silly to provide an answer with a reference that directly contradicts it :hehe:.
Tom
February 20, 2012 at 1:00 am
Hello Everybody,
My answer was : 1, 2, 3, 5.
I think it is the correct answer acordind to http://msdn.microsoft.com/en-us/library/ms190736.aspx
Hash recursion and hash bailout cause reduced performance in your server. To eliminate or reduce the frequency of hash recursion and bailouts, do one of the following:
Make sure that statistics exist on the columns that are being joined or grouped.
If statistics exist on the columns, update them.
Use a different type of join. For example, use a MERGE or LOOP join instead, if appropriate.
Increase available memory on the computer. Hash recursion or bailout occurs when there is not enough memory to process queries in place and they need to spill to disk.
Creating or updating the statistics on the column involved in the join is the most effective way to reduce the number of hash recursion or bailouts that occur.
February 20, 2012 at 1:52 am
:crying:I want my Points back
February 20, 2012 at 2:10 am
Good question that made me think. Shame the quoted reference doesn't match the 'correct' answers.
February 20, 2012 at 2:42 am
ipounder (2/20/2012)
Good question that made me think. Shame the quoted reference doesn't match the 'correct' answers.
+2
February 20, 2012 at 3:23 am
This was removed by the editor as SPAM
February 20, 2012 at 3:31 am
I have to agree with khelloufsofiane and others: the answers given in your "correct" response did not seem to co-incide with those which appear in the documentation.
Either you are, or I am, losing the ability to read.
Ken.
You never know: reading my book: "All about your computer" might just tell you something you never knew!
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February 20, 2012 at 3:53 am
I think there's a BUG in the "Contribution Editor". I couldn't believe that so many questions are wrong.
😎
Steve, please correct the points and the "Contribution Editor".
February 20, 2012 at 4:09 am
Ah! the disappointment of thinking you've done really well and ticked all the right boxes to then be told you are wrong!... however, faith can then be restored by clicking on Join the discussion and finding that you were right after all.
Phew 😀
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