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 Posted Monday, January 2, 2012 10:50 AM
 SSCrazy Eights Group: General Forum Members Last Login: Today @ 8:50 AM Points: 9,825, Visits: 11,896
 Hugo Kornelis (1/1/2012)Jeff Moden (1/1/2012)Tom Brown (12/31/2011)My word Jeff! A lot of thinking for a single point, considering I got 7 points for counting Santa's reindeer.Keep 'em coming. I need the mental exercise.I may have missed it but I didn't see a place on the QOTD entry form to assign a point value. If I did, I'd likely have given it 3 points even with the copyable code. You didn't miss anything, Jeff. Steve decides the amount of points to assign to each question. And he always assigns ridiculously high amounts of points to the seasonal "humor" questions.Yes, he's done that again today (for a seasonal simple arithmetic question). Tom
Post #1228963
 Posted Tuesday, January 3, 2012 3:06 AM
 SSCommitted Group: General Forum Members Last Login: Wednesday, November 30, 2016 4:43 AM Points: 1,854, Visits: 2,278
 Jeff Moden (12/28/2011)To be sure, I made a terrible mistake. ISNULL isn't SARGable.That is just a perspective thing.Your 'terrible mistake' challenged something I believed to be true and highlighted a lots of things I didn't know.Three days into the new year and I now have a much better understanding of how indexes are used.I think it is going to be a good year.Many thanks to yourself, Hugo and Paul
Post #1229108
 Posted Tuesday, January 3, 2012 4:43 AM
 SSC-Forever Group: General Forum Members Last Login: Today @ 7:14 AM Points: 42,072, Visits: 39,455
 Steve updated the explanation with the lessons learned from this thread for me yesterday. --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." Helpful Links:How to post code problemsHow to post performance problems
Post #1229147
 Posted Tuesday, January 3, 2012 4:46 AM
 SSC-Forever Group: General Forum Members Last Login: Today @ 7:14 AM Points: 42,072, Visits: 39,455
 440692 I am just a number (1/3/2012)Jeff Moden (12/28/2011)To be sure, I made a terrible mistake. ISNULL isn't SARGable.That is just a perspective thing.Your 'terrible mistake' challenged something I believed to be true and highlighted a lots of things I didn't know.Three days into the new year and I now have a much better understanding of how indexes are used.I think it is going to be a good year.Many thanks to yourself, Hugo and PaulThank you for the kind words. And, I agree... once again, the discussions are what really paid off on these fine forums. --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." Helpful Links:How to post code problemsHow to post performance problems
Post #1229149
 Posted Thursday, January 12, 2012 4:02 PM
 SSCertifiable Group: General Forum Members Last Login: Today @ 7:04 AM Points: 5,669, Visits: 11,173
 Explanation: Nothing is stopping an INDEX SEEK from being used and answer "A" is the correct answer. Actually something does.It's named "bookmark lookup".
Post #1235293
 Posted Thursday, January 12, 2012 9:55 PM
 SSCrazy Eights Group: General Forum Members Last Login: Today @ 6:42 AM Points: 9,932, Visits: 11,347
 Sergiy (1/12/2012)Explanation: Nothing is stopping an INDEX SEEK from being used and answer "A" is the correct answer. Actually something does.It's named "bookmark lookup".There is no 'bookmark lookup' in this case as Jeff's explanation of point H reveals: the non-clustered index is covering for the query.'Bookmark lookup' is out-of-date now: they are referred to as an RID Lookup for a heap, or Key Lookup for a clustered index. The lookup operation is a seek on the clustered index key, or direct navigation to a row locator (RID) if the base table is a heap. Paul WhiteSQLPerformance.comSQLblog.com@SQL_Kiwi
Post #1235368
 Posted Sunday, January 15, 2012 4:19 PM
 SSCertifiable Group: General Forum Members Last Login: Today @ 7:04 AM Points: 5,669, Visits: 11,173
 SQL Kiwi (1/12/2012)There is no 'bookmark lookup' in this case as Jeff's explanation of point H reveals: the non-clustered index is covering for the query.Sounds right.I need to find out what did I do wrong to make it do scan instead of seek in my test case.
Post #1236354
 Posted Tuesday, January 24, 2012 1:55 AM
 SSCoach Group: General Forum Members Last Login: 2 days ago @ 2:09 AM Points: 15,501, Visits: 13,163
 Great question, thanks. How to post forum questions.Need an answer? No, you need a question.What’s the deal with Excel & SSIS?Member of LinkedIn. My blog at SQLKover. MCSA SQL Server 2012 - MCSE Business Intelligence
Post #1240664
 Posted Thursday, March 15, 2012 8:02 AM
 SSCommitted Group: General Forum Members Last Login: Thursday, February 11, 2016 3:54 PM Points: 1,619, Visits: 1,360
 Thanks for the question. Even though I got it wrong, I learned a lot. _________________________________seth delcontehttp://sqlkeys.com
Post #1267508
 Posted Saturday, January 25, 2014 5:48 AM
 Ten Centuries Group: General Forum Members Last Login: Wednesday, November 30, 2016 5:47 AM Points: 1,286, Visits: 1,858
 I thought answer B is including answer A also, that is why i did not check answer A.and i did a big mistake by not reading "select 2"learned a lot through the explanation given by all. thanks every one
Post #1534717

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