mysql> select case when created_time >= '2017-01-01'
-> and created_time < '2017-01-02 10:43:20'
-> then '2017-01-01'(http://www.amjmh.com/v/BIBRGZ_558768/)
-> when created_time >= '2017-01-02 10:43:20'
-> and created_time < '2017-01-03 21:26:40'
-> then '2017-01-02 10:43:20'
-> when created_time >= '2017-01-03 21:26:40'
-> and created_time < '2017-01-05 08:10:00'
-> then '2017-01-03 21:26:40'
-> else '2017-01-05 08:10:00'
-> end min_dt,
-> case when created_time >= '2017-01-01'
-> and created_time < '2017-01-02 10:43:20'
-> then '2017-01-02 10:43:20'
-> when created_time >= '2017-01-02 10:43:20'
-> and created_time < '2017-01-03 21:26:40'
-> then '2017-01-03 21:26:40'
-> when created_time >= '2017-01-03 21:26:40'
-> and created_time < '2017-01-05 08:10:00'
-> then '2017-01-05 08:10:00'
-> else '2017-01-06 18:53:20'
-> end max_dt,
-> count(*)
-> from t_source
-> group by case when created_time >= '2017-01-01'
-> and created_time < '2017-01-02 10:43:20'
-> then '2017-01-01'
-> when created_time >= '2017-01-02 10:43:20'
-> and created_time < '2017-01-03 21:26:40'
-> then '2017-01-02 10:43:20'
-> when created_time >= '2017-01-03 21:26:40'
-> and created_time < '2017-01-05 08:10:00'
-> then '2017-01-03 21:26:40'
-> else '2017-01-05 08:10:00'
-> end,
-> case when created_time >= '2017-01-01'
-> and created_time < '2017-01-02 10:43:20'
-> then '2017-01-02 10:43:20'
-> when created_time >= '2017-01-02 10:43:20'
-> and created_time < '2017-01-03 21:26:40'
-> then '2017-01-03 21:26:40'
-> when created_time >= '2017-01-03 21:26:40'
-> and created_time < '2017-01-05 08:10:00'
-> then '2017-01-05 08:10:00'
-> else '2017-01-06 18:53:20'
-> end;
+---------------------+---------------------+----------+
| min_dt | max_dt | count(*) |
+---------------------+---------------------+----------+
| 2017-01-01 | 2017-01-02 10:43:20 | 249999 |
| 2017-01-02 10:43:20 | 2017-01-03 21:26:40 | 250000 |
| 2017-01-03 21:26:40 | 2017-01-05 08:10:00 | 250000 |
| 2017-01-05 08:10:00 | 2017-01-06 18:53:20 | 250002 |
+---------------------+---------------------+----------+
4 rows in set (4.86 sec)
---------------------