reference: http://www.snowfrog.net/2005/11/16/backup-multiple-databases-into-separate-files/
#!/bin/bash
# sonia 16-nov-05
# backup each mysql db into a different file, rather than one big file
# as with --all-databases - will make restores easier
USER="root"
PASSWORD="secret"
OUTPUTDIR="/var/lib/bacula"
MYSQLDUMP="/usr/bin/mysqldump"
MYSQL="/usr/bin/mysql"
# clean up any old backups - save space
rm "$OUTPUTDIR/*gz" > /dev/null 2>&1
# get a list of databases
databases=`$MYSQL --user=$USER --password=$PASSWORD \
-e "SHOW DATABASES;" | tr -d "| " | grep -v Database`
# dump each database in turn
for db in $databases; do
echo $db
$MYSQLDUMP --force --opt --user=$USER --password=$PASSWORD \
--databases $db | gzip > "$OUTPUTDIR/$db.gz"
done