Need a Subquery to delete the previous dates

• smharabbani40

  SSC Enthusiast

  Points: 143

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  July 10, 2013 at 1:16 am

  #296225

  I have created one table like below

  create table Verification(id int,date datetime)

  inserted values like

  insert into Verification values(1,'2013-07-10 03:12:05.397')

  insert into Verification values(1,'2013-07-09 03:12:05.397')

  insert into Verification values(1,'2013-07-08 03:12:05.397')

  insert into Verification values(2,'2013-07-10 03:12:05.397')

  insert into Verification values(2,'2013-07-09 03:12:05.397')

  insert into Verification values(2,'2013-07-08 03:12:05.397')

  insert into Verification values(3,'2013-07-10 03:12:05.397')

  insert into Verification values(3,'2013-07-09 03:12:05.397')

  insert into Verification values(3,'2013-07-08 03:12:05.397')

  I want to delete all the records except for the id who's have the max date.

  output record should be like this.

  ID date

  1 2013-07-10 03:12:05.397'

  2 2013-07-10 03:12:05.397'

  3 2013-07-10 03:12:05.397'

• Dwain Camps

  SSC Guru

  Points: 86978

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  July 10, 2013 at 1:22 am

  #1631091

  Delete through a CTE thusly:

  WITH Rows2Delete AS (

  SELECT id, [date], rn=ROW_NUMBER() OVER (PARTITION BY id ORDER BY [date] DESC)

  FROM Verification)

  DELETE FROM Rows2Delete

  WHERE rn <> 1;

  SELECT * FROM Verification;

  ---

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  The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.

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