Home Page for the TeradataForum

Archives of the TeradataForum

Message Posted: Thu, 19 May 2005 @ 09:28:14 GMT

  <Prev Next>   <<First <Prev Next> Last>>  

Subj:   Re: Why Multiload won't support USI
From:   Anomy Anom

<-- Anonymously Posted: Thursday, May 19, 2005 05:23 -->

Hi Abdul,

the reason is that USI are not distributed across the AMPs AS the base table (typically the distribution is different, a USI row could be located on an AMP that is different from the base table row AMP). Whereas NUSI are "AMP local"; that is, the NUSI subtable is distributed as the base table.

This is the reason why you can't load a table with USI; this is also the reason why in a MLD task you can't change the value of the primary index, because it (the row) could "jump" on another AMP depending on the hash value generated by the hash algorithm.

Hope this helps,


  <Prev Next>   <<First <Prev Next> Last>>  
  Top Home Privacy Feedback  
Copyright for the TeradataForum (TDATA-L), Manta BlueSky    
Copyright 2016 - All Rights Reserved    
Last Modified: 15 Jun 2023