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Message Posted: Tue, 20 Nov 2012 @ 16:08:26 GMT

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Subj:   Re: How to generate Surrogate Key using CSUM?
From:   Dieter Noeth

Dipti Prakash Lenka wrote:

  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 ?  

Why don't you simply Explain this query?

It's the same value for each row and the optimizer will retrieve it only once.


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