select s.okpo,
s.result_called,
case
when nvl trunc(ivr.date_called,0) >= to_date('07:00','HH24:MI') and nvl trunc(ivr.date_called,0) < to_date('08:00','HH24:MI')
then '07:00 - 08:00'
when nvl trunc(ivr.date_called,0) >= to_date('08:00','HH24:MI') and nvl trunc(ivr.date_called,0) < to_date('09:00','HH24:MI')
then '08:00 - 09:00'
when nvl trunc(ivr.date_called,0) >= to_date('09:00','HH24:MI') and nvl trunc(ivr.date_called,0) < to_date('10:00','HH24:MI')
then '09:00 - 10:00'
when nvl trunc(ivr.date_called,0) >= to_date('10:00','HH24:MI') and nvl trunc(ivr.date_called,0) < to_date('11:00','HH24:MI')
then '10:00 - 11:00'
when nvl trunc(ivr.date_called,0) >= to_date('11:00','HH24:MI') and nvl trunc(ivr.date_called,0) < to_date('12:00','HH24:MI')
then '11:00 - 12:00'
end cikl,
s.date_action
from imp_ivr s
where s.result_called_id = 1
and s.date_insert = trunc(sysdate)

что не так?