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Archives of the TeradataForum
Message Posted: Mon, 19 Nov 2012 @ 21:14:55 GMT
Subj: | | Re: How to generate Surrogate Key using CSUM? |
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From: | | Nimmala, Meher |
Hi Dipti,
There is an identity column feature in Teradata which can generate surrogate key. But as per my opinion generating surrogate key using below
SQL (CSUM or Row_Number - Preferred) will be better option. Always do not assume product join is not good. In this case, you are joining only 1
record (max value from target table) with other table and does not make difference. Though target table grows, from your query you are getting max
value, so does not hit performance also.
Do not use Rank function as it may generate same values in some cases and leads to failure of Unique violation.
Regards,
Meher
Teradata India Pvt Ltd.
Mumbai
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