SELECT
device_id, gender,
case
when age < 20 then "20岁以下"
when age < 24 then "20-24岁"
when age >= 25 then "25岁及以上"
when age IS NULL then "其他"
end age_cut
FROM user_profile;
SELECT
device_id, gender,
case
when age < 20 then "20岁以下"
when age < 24 then "20-24岁"
when age >= 25 then "25岁及以上"
when age IS NULL then "其他"
end age_cut
FROM user_profile;