The Oracle mysql client has an odd behavior if your server uses latin1 as default character-set-server. Command mysql --version mysql Ver 8.0.31-0ubuntu0.20.04.2 for Linux on x86...

mysql --default-character-set utf8mb4 -e "SHOW VARIABLES LIKE '%char%';" Expectation utf8mb4 will be used as character set in this session. Reality The mysql client falls back to latin1...

...Right after that we had a look into the logrotation-configuration and saw that the mysqladmin-command is used to check if the server is running in order to rotate...

...log flush-slow-log fi endscript } From the documentation of the parameter ping of the mysqladmin-command we can see that the command tries to access the database and if...

makandra Operations

NAME W STATUS CHECK ACT BCK QCUR QMAX SCUR SMAX SLIM STOT >>> mysql-front FRONTEND 0 OPEN 0 0 0 0 0 0 75 0 >>> mysql-back...

...hatop and pressing F10. Via socat it works this way: # disable server / echo "disable server mysql-back/mysql1" | socat unix-connect:/var/run/haproxy/haproxy.stat stdio Now no new connections will be opened...

makandra Operations

Enabling this shows each column in a own line. It's similar to mysql \G \x on Prevent users FROM connecting to a database ALTER DATABASE foo_db CONNECTION...

$ mariabackup --prepare --target-dir ./mariabackup $ mariabackup --move-back --target-dir ./mariabackup # chown -R mysql:mysql /var/lib/mysql/ # systemctl start mariadb

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mysqlperformanceblog.com

When MySQL refuses to use your index, there's a number of things that you may be doing wrong. One of them might be conditions with improper data types.

...assume you have a users table with an email field (varchar) which is indexed. MySQL will use the index when your query is well-formed: mysql> EXPLAIN SELECT * FROM users...

If replication is broken by a simple invalid query, i.e. grants change, etc. you can force-skip that query:

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