Help with Constraint

• cmcilvoy

  Ten Centuries

  Points: 1015

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  March 22, 2004 at 11:06 am

  #163311

  Table

  ID

  CatID

  ProductName

  I want to write a constraint that would require distinct productname per CatID.

  thanks

   

   

  
  </cm>

• Antares686

  SSC Guru

  Points: 125444

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  March 22, 2004 at 11:17 am

  #499827

  Create a composite index that contains both ProductName and CatID and using EM set to Unique Constraint.

  Or SQL Syntax

  ALTER TABLE dbo.tblName ADD CONSTRAINT

   IX_tblName UNIQUE NONCLUSTERED

   (

   ProductName,

   CatID

  &nbsp ON [PRIMARY]

  Above assumes ProductName will have more distinct values and thus a higher statistics factor will be produced for the Constraint index.