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Message Posted: Tue, 18 Jan 2005 @ 09:13:26 GMT


     
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Subj:   Re: FastLoad VS MLoad
 
From:   Victor Sokovin

  If your data were to be badly skewed(i.e. considering NUPI) and you have a SET table to be loaded then MLOAD takes a longer time - because it checks every row to be inserted for duplicates. Added to this error logging (logging the duplicate row to the error table) would again take some cosiderable time. You could avoid this if you were to have a MULTISET table as the target table to be loaded.  



If MULTISET is not an option, IGNORE DUPLICATE ROWS in the MultiLoad script might help make the competition a bit more fair. The target table should not have a UPI, though. Otherwise, specifying this clause won't help as it will be ignored.

I still wonder, however, whether this will explain the whole run time difference. One extra hour for 60 mln rows is a lot.


Regards,

Victor



     
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