题解 | #查看不同年龄段的用户明细#

-- 方法1CASE WHEN多重判断
# SELECT
#     device_id,
#     gender,
#     CASE
#         WHEN age >= 25 THEN '25岁及以上'
#         WHEN age >= 20 THEN '20-24岁'
#         WHEN age >= 0 THEN '20岁以下'
#         ELSE '其他'
#     END AS age_cut
# FROM
#     user_profile

-- 方法2多重IF
SELECT
    device_id,
    gender,
    IF(age >= 25, '25岁及以上',
        IF(age >= 20, '20-24岁',
            IF(age >= 0, '20岁以下', '其他'))) AS age_cut
FROM
    user_profile