• List views : SHOW FULL TABLES IN database_name WHERE TABLE_TYPE LIKE 'VIEW';
• show engine for all tables : SELECT TABLE_NAME, ENGINE FROM information_schema.TABLES WHERE TABLE_SCHEMA = 'dbname';
• count occurrences for each value: select userid, count(userid) as cuid from sessions group by userid order by cuid desc limit 5;
• List users : SELECT User,Host FROM mysql.user;
• list runtime information :

show global status;
show variables;
SHOW PROCESSLIST \G;

• mysqldumpslow, un tool pour dumper les slow queries en pretty print
• Get replication information : show slave status\G
• a small script to skip replication errors upon initialising it :

#!/usr/bin/env bash
set -eu

while true; do
    status=$(mysql --execute="show slave status\G"|grep "Seconds_Behind_Master:"|awk '{print $2}')
    if [ $status == "NULL" ]; then
        mysql --execute="show slave status\G" | grep "Last_SQL_Error:"
        mysql --execute="set global sql_slave_skip_counter=1; start slave;"
    fi
    sleep 0.01
done

• Préparer le lancement d'une réplication : FLUSH TABLES ; FLUSH TABLES WITH READ LOCK; SHOW MASTER STATUS; system lvcreate -s -L 5G -n snap-20110925 /dev/system/var_lib_mysql; UNLOCK TABLES;
• Minimum privileges for bareos :

GRANT USAGE ON *.* TO 'bareos'@'localhost' IDENTIFIED BY 'bareos';
GRANT SELECT, LOCK TABLES, SHOW VIEW, EVENT, TRIGGER ON *.* TO 'bareos'@'localhost'