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Archives of the TeradataForum
Message Posted: Fri, 30 Nov 2012 @ 22:39:22 GMT
| Subj: | | Re: SET table with UPI |
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| From: | | Anomy Anom |
< -- Anonymously Posted: Friday, November 30, 2012 17:29 -- >
Technically yes, the SET table may be checked for duplicates even with UPI. But this check only considers other rows with the same RowHash, so
if the PI is unique the database is generally looking for other rows to compare against but finding none. It is doubtful you will notice any
performance improvement for MULTISET. Even with NUPI, it is only when there are many existing rows with same PI/RowHash to compare against that
duplicate checking becomes costly.
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