with main as (
select '1168126809' as bzno from dual union all
select '1168126809' as bzno from dual union all
select '1168126811' as bzno from dual union all
select '1168126812' as bzno from dual union all
select '1168126812' as bzno from dual union all
select '1168126812' as bzno from dual union all
select '1168126813' as bzno from dual union all
select '1168126814' as bzno from dual
)
select sum(case when (cnt = 1) then 1 else 0 end) as "사업자번호가 하나인건"
     , sum(case when (cnt > 1) then 1 else 0 end) as "사업자번호가 하나이상인건"
  from (
  select bzno
       , count(*) cnt
    from main
   group by bzno
       )
 

사업자번호가 하나인건과 하나이상건을 각각 구하고자 하신다면

having count(*) =1 또는having count(*) > 1을 이용하시면 됩니다.

그럼, 오늘도 좋은날 되세요..

SELECT COUNT(CASE WHEN COUNT(*) = 1 THEN 1 END) cnt_1
     , COUNT(CASE WHEN COUNT(*) > 1 THEN 1 END) cnt_2
  FROM t
 GROUP BY bzno
;