select
    DISTRICT_CODE,
    case 
        when trim(DISTRICT_NAME) = '' then '不明'
        when DISTRICT_NAME is NULL then '不明'
        else DISTRICT_NAME
    end as DISTRICT_NAME,
    TOTAL_AMT,
    -- quote(district_name) as qd,
    MALE_AMT,
    FEMALE_AMT
from
    POPULATION
order by
    DISTRICT_CODE