Entries Published On May, 2013
Optimizing MIN and MAX MySQL Functions
MySQL can optimize aggregate functions like MIN and MAX as long as the columns specified are indexed. This means that, in the case of MIN and MAX, the optimizer should be able to identify the highest and lowest values of an indexed column from the B-Tree index. Say I have a table like below: CREATE …
Pacemaker Failed Actions ‘not installed’ And ‘not configured’
Playing around with Percona Replication Manager, and being new to Pacemaker, some errors were somewhat cryptic. May 26 09:53:39 [2181] ha01.localdomain pengine: notice: unpack_rsc_op: Preventing p_mysql from re-starting on ha02.localdomain: operation monitor failed 'not installed' (rc=5) May 26 09:53:39 [2181] ha01.localdomain pengine: notice: unpack_rsc_op: Preventing op from re-starting on ha02.localdomain: operation monitor failed 'not installed' …
MySQL Backups, The Tools So Far
Backups is one of the most important part of any MySQL deployment, and nowadays, there’s a number of tools to choose from depending on how your organization implements them. The purpose of this post is to enumerate the main tools and some helpers that makes backing up and testing/restoring your backups more convenient. By all …