…GROUP BY implementation “Later one of the clients performing group bys on tens of millions of rows complained and so ORDER BY…GROUP BY. So, we get a SQL92 compliant full group by clause. Unfortunately, the description column is included first in the group by clause….and MySQL…
Post: Quickly finding unused indexes (and estimating their size)
December 5, 2012 By 2 Comments
… stats from several servers In the case of this client, they had a master and several slaves taking …group by t.table_schema, t.table_name, i.index_name; Now I can query this view to see my indexes: mysql… can take quite some time. All the normal tricks and tips about doing a long blocking schema …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… information about LVM devices, volume groups, and logical volumes. At this …MySQL server. I mean, let’s just assume the physical hardware and the machine setup is fine, and the client… slow /path/to/slow.log By default, this outputs the top …We share all sorts of dirty tricks and neat ideas with each …
