Archives of the TeradataForum

Message Posted: Thu, 27 Mar 2008 @ 20:42:52 GMT

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

<-- Anonymously Posted: Thu, 27 Mar 2008 13:00 -->

Conceptually, DISTINCT builds the entire answer set, then removes duplicates. GROUP BY may be able to do the aggregation sooner and/or do "AMP- local" partial aggregation - but there is extra overhead, so if very few rows are eliminated the DISTINCT actually performs better.

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