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 Posted Friday, October 02, 2009 4:00 AM
 Forum Newbie Group: General Forum Members Last Login: Friday, February 17, 2012 4:39 AM Points: 4, Visits: 17
 Hello. I use SQL Server 2005 and I'm calculating the age of patients in the following manner:DATEDIFF(DAY, birthdate, operationdate)/365.25The output always seems to be a decimal with 6 decimal digits. The rounding problem arises with border cases like for instance an age of 60.444445. If you round this properly it should result in 60.45 and that should result in 60.5. However, when I use ROUND(60.444445, 1) it results in 60.4!The problem is that SQL Server seems to ignore the digits after the rounding border. ROUND(60.449999, 1) for instance also results in 60.4. It seems to truncate it 1 position behind the rounding index and starts rounding after that. I found out that using the ROUND() function repeatedly in the following manner solves the issue but it is a bit ridiculous:PRINT ROUND(ROUND(ROUND(ROUND(ROUND(60.444445, 5), 4), 3), 2), 1)Is there any other way to solve this and am I missing something?Thanks in advance!
Post #796803
 Posted Friday, October 02, 2009 4:16 AM
 SSCommitted Group: General Forum Members Last Login: Monday, April 14, 2014 7:26 AM Points: 1,949, Visits: 8,291
 Heres how to calculate an ageselect CASEWHEN dateadd(year, datediff (year, d1, d2), d1) > d2THEN datediff (year, d1, d2) - 1ELSE datediff (year, d1, d2)END as AgeI'll take a look at the rounding issue though...
Post #796805
 Posted Friday, October 02, 2009 4:33 AM
 SSCommitted Group: General Forum Members Last Login: Monday, April 14, 2014 7:26 AM Points: 1,949, Visits: 8,291
 I think you are wrong in your assessment of round though,round(60.444445,1) = 60.4 This PRINT ROUND(ROUND(ROUND(ROUND(ROUND(60.444445, 5), 4), 3), 2), 1)works because you are rounding a rounded , rounded, rounded , rounded number (ie the 5 has for want of a better word been cascaded up)
Post #796810
 Posted Friday, October 02, 2009 6:40 AM
 Forum Newbie Group: General Forum Members Last Login: Friday, February 17, 2012 4:39 AM Points: 4, Visits: 17
 For some reason that way of rounding was in my head. But I spoke with others about and I think SQL Server does round it correctly yes.
Post #796835
 Posted Friday, October 02, 2009 7:38 PM
 SSC-Dedicated Group: General Forum Members Last Login: Yesterday @ 11:47 PM Points: 35,959, Visits: 30,252
 Dave Ballantyne (10/2/2009)Heres how to calculate an ageselect CASEWHEN dateadd(year, datediff (year, d1, d2), d1) > d2THEN datediff (year, d1, d2) - 1ELSE datediff (year, d1, d2)END as AgeI'll take a look at the rounding issue though...That's one of the simplest I've seen. Correctly handles the Feb 29 problem that most other's don't handle, too! --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." -- 04 August 2013(play on words) "Just because you CAN do something in T-SQL, doesn't mean you SHOULDN'T." --22 Aug 2013Helpful Links:How to post code problemsHow to post performance problems
Post #797330
 Posted Monday, October 05, 2009 2:34 AM
 SSCommitted Group: General Forum Members Last Login: Monday, April 14, 2014 7:26 AM Points: 1,949, Visits: 8,291
 Cant take the credit for it ...http://windowsitpro.com/article/articleid/14267/how-can-i-calculate-someones-age-in-sql-server.html
Post #797711
 Posted Monday, October 05, 2009 5:58 AM
 SSC-Dedicated Group: General Forum Members Last Login: Yesterday @ 11:47 PM Points: 35,959, Visits: 30,252
 Shoot... the link is broken. Thanks anyway, Dave. --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." -- 04 August 2013(play on words) "Just because you CAN do something in T-SQL, doesn't mean you SHOULDN'T." --22 Aug 2013Helpful Links:How to post code problemsHow to post performance problems
Post #797801
 Posted Monday, October 05, 2009 7:05 AM
 SSCommitted Group: General Forum Members Last Login: Monday, April 14, 2014 7:26 AM Points: 1,949, Visits: 8,291
 Seems fine now, just a temporary thing i guess.TBH , its hardly worth the click though simple Q and A
Post #797849
 Posted Monday, October 05, 2009 7:08 AM
 SSC-Dedicated Group: General Forum Members Last Login: Yesterday @ 11:47 PM Points: 35,959, Visits: 30,252
 Hmmmm.... something must be wrong on my end. It keeps giving me a 404 error.Q & A's are sometimes pretty rich in information like the little date jewel you found. --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." -- 04 August 2013(play on words) "Just because you CAN do something in T-SQL, doesn't mean you SHOULDN'T." --22 Aug 2013Helpful Links:How to post code problemsHow to post performance problems
Post #797855

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