/* WITH A as (
select count(*) from HOSPITALIZATION
GROUP BY PF_CODE
)*/


select a.PF_CODE as 都道府県コード, PF_NAME as 都道府県名, INP_YES*100/(INP_YES+INP_NO+UNIDENTIFIED) as 入院率 
from HOSPITALIZATION a
JOIN PREFECTURE b on a.PF_CODE=b.PF_CODE;