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Message Posted: Tue, 04 Jan 2011 @ 09:14:08 GMT 
 
  
 
 
 
 
  
|  Subj:  |   |  Teradata architecture questions?  |   
|     |   
|  From:  |   |  desai kaushik  |   
  
 
 
  
1.) primary index access rows using only row hash. 
if two different primary index values come out of a hashing algorithm with the same row hash value like 
     data values    1254    7769   <- data values
                             |          |
                            \/         \/
                          hash algorithm
                            |           |
                           \/          \/
                         22936     22936
 how teradata handles this conditions? 
i know there is concept of adding a uniqueness value, but can any one explain how it is been used for accessing rows  even though we have not
specified uniqueness value in our query. 
 
 
 
 
   
 
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