select sl_servers.name
if (sl_servers.virtual=1,select sl_racks.rack FROM sl_servers INNER JOIN sl_racks on sl_servers.place=sl_racks.id ,NULL)
if (sl_servers.virtual=0,select sl_hv.name as place from sl_servers INNER JOIN sl_hv on sl_servers.place=sl_hv.id ,NULL)
from sl_servers

BEGIN
if (sl_servers.virtual=0) 
then
select sl_racks.rack FROM sl_servers INNER JOIN sl_racks on sl_servers.place=sl_racks.id;
else
select sl_hv.name as place from sl_servers INNER JOIN sl_hv on sl_servers.place=sl_hv.id;
end if;
end; 

+------------------+------------+------------------+
| name             | rack       | hv               |
+------------------+------------+------------------+
| 1st14            | NULL       | esx72            |
| esx72            | RACK-5     | NULL             |
+------------------+------------+------------------+