每个月如何获取 SUM 和 COUNT 数据？

Question

例如我有数据

| S | Q |   Date   |
|===|===|==========|
| A | 2 |2020-11-23|
| B | 5 |2020-11-24|
| A | 1 |2020-12-01|
| B | 3 |2020-12-02|
| A | 2 |2020-12-03|
| B | 1 |2020-12-14|
| B | 2 |2021-01-02|

如何查询我是否想要得到这样的结果 v

| S | T | tQ | Last Date |
|===|===|====|===========|
| B | 1 |  2 | 2021-01-02|
| B | 2 |  4 | 2020-12-14|
| A | 2 |  3 | 2020-12-03|
| B | 1 |  5 | 2020-11-24|
| A | 1 |  2 | 2020-11-23|

T : count(S) in each month
tQ: sum(Q) in each month

Answer 1

嗯。 . .这看起来像聚合：

select max(date), s, count(*) as t, sum(q)
from t
group by year(date), month(date), s;