|  |  | Archives of the TeradataForumMessage Posted: Mon, 10 Feb 2003 @ 15:14:30 GMT
 
 
  
| Subj: |  | Re: V2R5 Identity Column Population |  |  |  | From: |  | Fred W Pluebell |  
 Because Teradata reserves a "batch" of identity values at a time and caches them (on each AMP for INSERT/SELECT) for better parallelism.
The "INCREMENTING BY" clause only applies within a batch. You have to make a tradeoff between "gaps" in the numbers and insert
performance. The batch size is controlled by a dbscontrol "general" field (IdCol Batch Size), which defaults to 100,000.  From your sample, I'd guess
your system has 20 AMPs and dbscontrol is set to the max of 1,000,000. 
 
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