mysql如何分别按年/月/日/周分组统计数据详解

-- 按年
select date_format(create_time, '%Y') years,avg(age),count(gender) from student where create_time > "2022-01-01 00:00:00" and create_time < "2022-07-19 19:58:03" group by years;
-- 按月
select date_format(create_time, '%Y-%m') months,avg(age),count(gender) from student where create_time > "2022-01-01 00:00:00" and create_time < "2022-07-19 19:58:03" group by months;
-- 按周
select date_format(create_time, '%Y-%u') weeks,avg(age),count(gender) from student where create_time > "2022-01-01 00:00:00" and create_time < "2022-07-19 19:58:03" group by weeks;
-- 按日
select date_format(create_time, '%Y-%m-%d') days,avg(age),count(gender) from student where create_time > "2022-01-01 00:00:00" and create_time < "2022-07-19 19:58:03" group by days;

SELECT weeks,
CONCAT(LEFT(MIN(create_time),10),"至",LEFT(MAX(create_time),10)) AS date_range,
SUM(CASE WHEN nums <= 5 THEN 1 ELSE 0 END) AS '提问次数<=5',
 SUM(CASE WHEN nums > 5 AND nums<=10 THEN 1 ELSE 0 END) AS '5<提问次数<=10',
 SUM(CASE WHEN nums > 10 THEN 1 ELSE 0 END) AS '提问次数>10' 
 FROM 
 (SELECT FLOOR(DATEDIFF(create_time,'2021-01-01')/7)+1 weeks,
 create_time,uid,COUNT(*) AS nums 
  FROM `youTable` 
   WHERE create_time > "2021-01-01" 
   GROUP BY weeks,uid ORDER BY create_time ASC LIMIT 100000)
    AS topic_table GROUP BY weeks