Re: Slow COUNT + GROUP BY
Hi,
The subquery variant will probably not use a duplication elimination technique. It will use a temporary table instead. Anyhow, I am not sure the duplicate elimination will show up as a separate stage in the profiling.
Øystein Grøvlen,
Senior Principal Software Engineer,
MySQL Group, Oracle,
Trondheim, Norway
Subject
Views
Written By
Posted
1746
March 20, 2015 07:00AM
787
March 20, 2015 07:55AM
764
March 20, 2015 08:00AM
742
March 22, 2015 04:11PM
722
March 23, 2015 12:46AM
1102
March 23, 2015 02:45AM
1003
March 23, 2015 04:30AM
904
March 23, 2015 06:04AM
769
March 23, 2015 08:13AM
778
March 24, 2015 02:02AM
768
March 24, 2015 02:51AM
Re: Slow COUNT + GROUP BY
789
March 24, 2015 03:37AM
Sorry, you can't reply to this topic. It has been closed.
Content reproduced on this site is the property of the respective copyright holders.
It is not reviewed in advance by Oracle and does not necessarily represent the opinion
of Oracle or any other party.