well, I found it... it's a little different from what you directed me

For SMS:
Nokia-N900:~$ sqlite3 /home/user/.config/hildon-desktop/notifications.db "select count(id) from notifications where icon_name='general_sms'"
1

For Mails:
Nokia-N900:~$ sqlite3 /home/user/.config/hildon-desktop/notifications.db "select count(id) from notifications where icon_name='qgn_list_messagin'"
1

1 was the result, I had one mail and one sms, both unread