lxg » shell

June 11th, 2008 at 11:03 am

Shell script to optimize all tables in all databases (MySQL)

If you have many databases with many write operations, it may be that the table overhead takes a good amount of space. (This is due to the fact that MySQL doesn’t free the space of deleted entries.) With “optimizing” the tables, you can free that space.

Save the following script as /usr/local/sbin/optimizealltables.sh, make it chmod 700 (very important!), then replace YOURPASSWORD with your root MySQL password.

#!/bin/bash
 
MYSQL_LOGIN='-u root --password=YOURPASSWORD'
 
for db in $(echo "SHOW DATABASES;" | mysql $MYSQL_LOGIN | grep -v -e "Database" -e "information_schema")
do
        TABLES=$(echo "USE $db; SHOW TABLES;" | mysql $MYSQL_LOGIN |  grep -v Tables_in_)
        echo "Switching to database $db"
        for table in $TABLES
        do
                echo -n " * Optimizing table $table ... "
                echo "USE $db; OPTIMIZE TABLE $table" | mysql $MYSQL_LOGIN  >/dev/null
                echo "done."
        done
done