Help with order by and group by together

Question

Hi: I have a table with severity and devicename as two fields. I want a query which returns a list to include the records in the following order: Devicename with the highest severity at the top but all records should be grouped by devicename irrespective of the severity. Essentially I want the devicename record with the highest severity value at the top. Below is an example
Ticket1, DEVA, Severity:2
Ticket2, DEVA, Severity:4
Ticket3, DEVB, Severity:1
Ticket4, DEVB, Severity:8,
Ticket5, DEVC, Severity 3
Query's result should be as follows
Ticket3, DEVB
Ticket4, DEVB
Ticket1, DEVA
Ticket2, DEVA
Ticket5, DEVC
I have tried the following and it doesn't work.
Select a.devicename, b.severity
from (
select DEVICENAME,MIN(SEVERITY) from USERINCISUMMSTATUS group by DEVICENAME ORDER by MIN(SEVERITY) DESC) a,
USERINCISUMMSTATUS b
where a.devicename = b.devicename;TIA
Ray

Answer 1

Not a grouping but an ordering;
SQL> with t as (
   select 1 ticket, 'DEVA' devicename, 2 severity from dual union all
   select 2, 'DEVA', 4 from dual union all
   select 3, 'DEVB', 1 from dual union all
   select 4, 'DEVB', 8 from dual union all
   select 5, 'DEVC', 3 from dual)
select ticket,
   devicename,
   severity
from t
order by max(severity) over (partition by devicename) desc,
   devicename,
   severity
    TICKET DEVI   SEVERITY
         3 DEVB          1
         4 DEVB          8
         1 DEVA          2
         2 DEVA          4
         5 DEVC          3