Например:
for db_name in `mysql -u${mysql_user} -p${mysql_pass} -h${mysql_host} -e "show databases;" | tr -d "| " | grep -Ev "(Database|information_schema|performance_schema)"`
do
if [[ ${db_name} != "information_schema" ]] && [[ ${db_name} != _* ]] ; then
echo "Dumping database: ${db_name}"
mysqldump -u${mysql_user} -p${mysql_pass} -h${mysql_host} --events ${db_name} > ${dir_backup}${date_folder}/mysql/${db_name}.sql
fi
done