mysql> select concat(mail.mail_name,"@",domains.name) as name from mail,domains,accounts where mail.dom_id=domains.id and mail.account_id=accounts.id;
+--------------------------------+
| name |
+--------------------------------+
|
mail@plesk10.domain.com |
|
usersb@plesk10.domain.com |
+--------------------------------+
2 rows in set (0.00 sec)