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Message Posted: Tue, 20 Nov 2012 @ 13:25:03 GMT


     
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Subj:   Re: How to generate Surrogate Key using CSUM?
 
From:   Lenka, Dipti Prakash

Thanks Dieter.

If I go by the below given query, suppose we have million records in source table. In every each of records insert the subquery is getting MAX(subline_id) value from target table and having addition with ROW_NUMBER() value. And I guess it will happen million times. Is not a performance issue ?

     SELECT  ROW_NUMBER ()
        OVER (ORDER BY subline_id)
        + ( SELECT COALESCE(MAX(subline_id), 0)
            FROM ttmp.test_dipti_csum
          )
     FROM ttmp.test_dipti_csum  AS STAGE;

Thanks,

Dipti Prakash



     
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