substring_index(FIELD, sep, n)可以将字段FIELD按照sep分隔: 当n大于0时取第n个分隔符(n从1开始)之前的全部内容; 当n小于0时取倒数第n个分隔符(n从-1开始)之后的全部内容; select substring_index(substring_index(profile, ',', 3), ',', -1) as age, count(*) as number from user_submit group by age;