Home Page for the TeradataForum

Archives of the TeradataForum

Message Posted: Mon, 20 Jun 2011 @ 19:56:31 GMT

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

Subj:   Re: Distinct vs. group by in TD 13 onwards
From:   Pluebell, Fred

Prior to TD13:

DISTINCT performs better when the results are already nearly unique (few duplicates are being eliminated).

GROUP BY will perform better when large numbers of duplicates are being eliminated.

Starting with TD13, the optimizer will cost the alternative strategies rather choosing based on the syntax used.

  <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