check for NULL in a column

• ChrisM@Work

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  June 28, 2010 at 10:04 am

  #1185889

  priya__ (6/28/2010)

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  Thanks all for your reply,

  I cannot use SUM as I am counting a Key column here and if I use sum it will sum up the columne instead...

  I have to use count only...

  You can use both.

  COUNT with a preaggregate, SUM the COUNTS with a final aggregate, as shown.

  Commonly done with cross-tabs/pivots, see this[/url] excellent paper.

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• Gail Shaw

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  June 28, 2010 at 10:04 am

  #1185890

  You can use sum because, if you check the code that Gianluca posted, you're summing 1 or 0, 1 if that row is to be counted, 0 if it's not to be counted. Try it.

  Gail Shaw
  Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
  SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

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