-- SELECT DISTRICT_CODE, (CASE IFNULL(DISTRICT_NAME ,"") when "" then "不明" else DISTRICT_NAME end) as DISTRICT_NAME,TOTAL_AMT,MALE_AMT,FEMALE_AMT
-- 


-- order by DISTRICT_CODE

UPDATE POPULATION SET DISTRICT_NAME=(CASE IFNULL(DISTRICT_NAME ,"") when "" then "不明" else DISTRICT_NAME end);

-- UPDATE POPULATION SET DISTRICT_NAME=REPLACE(DISTRICT_NAME,NULL,"不明");

-- select * from POPULATION