with tmp_tbl_1 as (
select 
*
,'STEP' || row_number() over(partition by session_id order by ex_timestamp) as order_
from process_log 
)
,tmp_tbl_2 as (
select 
  *
  ,case when process_id = order_ then 'ok' else 'ng' end as check_
from tmp_tbl_1 
)
,tmp_tbl_3 as (
select * 
  ,sum(case when check_ = 'ng' then 1 when check_ = 'ok' then 0 else 1/0 end) over(partition by session_id order by ex_timestamp) as cum_ng
from tmp_tbl_2
)
select 
  process_id as PROCESS 
  ,count(case when cum_ng = 0 then session_id end) as CNT
from tmp_tbl_3
group by 1 
order by 1 
;