Re: Load overshooting ONE server
From: John Levine <johnl_at_iecc.com>
Date: Wed, 7 Sep 2016 16:09:55 +0000 (UTC)
Message-ID: <nqpe4j$1fe9$1_at_miucha.iecc.com>
Date: Wed, 7 Sep 2016 16:09:55 +0000 (UTC)
Message-ID: <nqpe4j$1fe9$1_at_miucha.iecc.com>
>IN particular I found that a nested query was far better performed by
>the application than by Mysql, on a multi-million record table
Depends on the query. I've gotten some impressive speedups by breaking a nested query in half by putting the nested query into a
CREATE TEMPORARY TABLE temptable (SELECT ... blah ...),
and making the outer query do
... WHERE foo in (SELECT foo FROM temptable)
Mysql optimizes that pretty well. Received on Wed Sep 07 2016 - 18:09:55 CEST