select
 PF.PF_CODE as 都道府県コード
,PF.PF_NAME as 都道府県名
,round(
cast(ifnull(HO.INP_YES,0) as real) / (
  + cast(ifnull(HO.INP_YES,0) as real)
  + cast(ifnull(HO.INP_NO,0)  as real)
  + cast(ifnull(HO.UNIDENTIFIED,0) as real)
  ) * 100
 ,1) as  入院率
-- ,都道府県毎の入院率 as 入院率
from 
PREFECTURE as PF
left join HOSPITALIZATION as HO
on PF.PF_CODE = HO.PF_CODE
order by 入院率 desc ,都道府県コード