table scan

• chisholmd

  SSCrazy

  Points: 2490

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  August 8, 2004 at 12:58 am

  #112112

  Hiya'll When I run this query the execution plan shows a table scan: (uid is primary key identity col 1,2,3,..)

  SELECT MAX(uid) AS Expr1

  FROM dbo.wmsLog

  It also shows a table scan if I do:

  Select top 1 from

  FROM dbo.wmsLog

  order by uid desc

  The table has about 1.6 million rows and the first query takes 59secs and the second is only slightly faster at 47secs.

  I would have thought with primary key it would have been allot faster as it simply has to seek the last index entry.

  Can anyone shed some light on this?

  Thanks

   

   

   

   

   

  Dave

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• chisholmd

  SSCrazy

  Points: 2490

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  August 8, 2004 at 9:48 pm

  #518118

  My bad, guess it was a late night and when I rebuilt the table I didn't add the primary key back in...duh!

  is much faster now

   

  Dave

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