MariaDB [Test]> select * from oo;
+---------------------+------+
| dte                 | flg  |
+---------------------+------+
| 2019-07-03 10:00:00 | 1    |
| 2019-07-03 10:26:11 | 0    |
| 2019-07-03 10:30:05 | 2    |
| 2019-07-03 10:31:05 | 0    |
| 2019-07-03 10:50:44 | 1    |
| 2019-07-03 10:59:01 | 2    |
| 2019-07-03 11:11:11 | 1    |
| 2019-07-03 11:54:56 | 0    |
| 2019-07-03 12:34:05 | 2    |
| 2019-07-03 12:44:05 | 2    |
| 2019-07-03 13:09:05 | 2    |
+---------------------+------+
11 rows in set (0.00 sec)

MariaDB [Test]> SELECT flg,COUNT(flg) AS icnt FROM oo where dte > '2019-07-03 10:00:00' and dte < '2019-07-03 12:00:00'  GROUP BY flg;
+------+------+
| flg  | icnt |
+------+------+
| 0    |    3 |
| 1    |    1 |
| 2    |    3 |
+------+------+
3 rows in set (0.00 sec)

ถ้าหากผมต้องการหาผลลบ ของ icnt 3-1 ต้องเรียงคำสั่งยังไงหรอคับ