Need max date from duplicare records.

Question

Need max date from duplicare records.

sachince61

Old Hand

Points: 329
More actions
July 9, 2013 at 9:07 am

#275066

Hello,
I have one table which have 3 columns
dt1 dt2 dt3 dt4 dt5
3/31/20113/30/20114/4/20113/30/20114/4/2011
10/24/201210/23/201210/27/201210/23/201210/27/2012
12/10/201212/8/201212/19/201212/8/201212/19/2012
12/20/201212/8/201212/19/201212/8/201212/19/2012
1/16/20131/14/20131/24/20131/14/20131/24/2013
when there comes duplicate record in dt2,dt3,dt4,dt5 then i just need max dt from dt1
else null
so can you please help me??

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Sean Lange SSC Guru Points: 286590 More actions · Answer 1

First things first. We need some consumable ddl and sample data. I created this for you this time so you can see what I mean.

if OBJECT_ID('tempdb..#Something') is not null

drop table #Something

set dateformat mdy

create table #Something

(

dt1 datetime,

dt2 datetime,

dt3 datetime,

dt4 datetime,

dt5 datetime

)

insert #Something

select '3/31/2011', '3/30/2011', '4/4/2011', '3/30/2011', '4/4/2011' union all

select '10/24/2012', '10/23/2012', '10/27/2012', '10/23/2012', '10/27/2012' union all

select '12/10/2012', '12/8/2012', '12/19/2012', '12/8/2012', '12/19/2012' union all

select '12/20/2012', '12/8/2012', '12/19/2012', '12/8/2012', '12/19/2012' union all

select '1/16/2013', '1/14/2013', '1/24/2013', '1/14/2013', '1/24/2013'

select * from #Something

So based on your sample data what do you want for desired output? I would like to point out that you do not have any duplicate rows here at all. Can you explain what you mean by that?

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Alexander Suprun SSCertifiable Points: 6253 More actions · Answer 2

Alexander Suprun

SSCertifiable

Points: 6253

July 9, 2013 at 9:43 am

#1630873

MAX

GROUP BY

Alex Suprun

Dwain Camps SSC Guru Points: 86948 More actions · Answer 3

As Alexander hinted at:

SELECT dt1=MAX(dt1), dt2, dt3, dt4, dt5

FROM #Something

GROUP BY dt2, dt3, dt4, dt5

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Voide Mr or Mrs. 500 Points: 548 More actions · Answer 4

You have more than 3 columns.

Have you written any code for this at all? Can you post it? What have you tried?

As others have said, MAX and Group By will help you.