Help with pl-sql query

Hello experts,

I am trying to build a report which will get the current count from each queue. However if it doesnt have a count, the queue is not listed. But i wanted to list all queues from my IN list in the query below and return zero if it doesnt have any count. Please see below my actual resultset and desired resultset. how can i change my below logic and make it look the way i wanted? Any easy suggestion?


select IWD_EXT_CUSTOMERSEGMENT as Virtual_queue,count(case when floor(((sysdate-received_at)*24*60*60)/3600)
between 0 and 12 then IWD_EXT_CUSTOMERSEGMENT else null end) open_less_than_12_hrs, count(case when floor(((sysdate-received_at)*24*60*60)/3600)
between 13 and 48 then IWD_EXT_CUSTOMERSEGMENT else null end) open_13_to_48_hrs, count(case when floor(((sysdate-received_at)*24*60*60)/3600) between 49 and 96
then IWD_EXT_CUSTOMERSEGMENT else null end) open_49_to_96_hrs, count(case when floor(((sysdate-received_at)*24*60*60)/3600) > 96 then IWD_EXT_CUSTOMERSEGMENT else null end)
open_greater_than_96_hrs FROM interactions where received_at between trunc(sysdate-1) and trunc(sysdate) and queue= 'ATTACK_Queued'
and assigned_to is null
and IWD_EXT_CUSTOMERSEGMENT in  ('A','B','C','D','E')
group by IWD_EXT_CUSTOMERSEGMENT order by IWD_EXT_CUSTOMERSEGMENT;

Current Result Set:
Virtaul_queue     Open_lessthan_hr   open_13_48  open 49_96_hr  open_grter_than_96_hr
A                          2                                 0                    6                          34
B                          5                                   2                  1                           23

Desired Result Set:

Virtaul_queue     Open_lessthan_hr   open_13_48  open 49_96_hr  open_grter_than_96_hr
A                          2                                 0                    6                          34
B                          5                                   2                  1                           23
C                         0                                   0                   0                           0
D                         0                                   0                   0                           0
E                        0                                   0                   0                           0