Zobacz wszystkie bazy:

$ mysql -u root --password='ElevenBenevolentElephants' -e "show databases;"
+--------------------+
| Database           |
+--------------------+
| information_schema |
| dspam              |
| ftp                |
| helpdesk           |
| mysql              |
| performance_schema |
+--------------------+

Zrób dump bazy dspam:

mysqldump -u root -p dspam >~/backup/${i}.sql;

Dump z gzipowaniem w locie:

for i in dspam ftp helpdesk; do 
    mysqldump -u root --password='ElevenBenevolentElephants' $i \
        | gzip -9 >~/backup/${i}_`date '+%F_%T'`.sql.gz; 
done