mysql - 对两行求和并按日期/总计排序

Question

需要一些帮助来构建查询，这是我目前的方案:

users:
+----+------------+
| id |  username  |
+----+------------+
| 1  |    rob     |
| 2  |    john    |
| 3  |    jane    | <--- jane never has donated
| 4  |    mike    | 
+----+------------+

donations:
+--------------------+------------+
|   uid   |  amount  |   date     |
+---------+----------+------------+
|    1    |    20    | 2013-10-10 | 
|    2    |    5     | 2013-10-03 | 
|    2    |    50    | 2013-09-25 |
|    2    |    5     | 2013-10-01 |
|    4    |    100   | 2012-10-01 | <-- past year
+---------+----------+------------+


Result I want:
+---------+-------------+---------+-------------+---------------+----------+ 
|    id   |   username  | amount  |   monthly   |  totalamount  |   total  |
+---------+-------------+---------+-------------+ --------------+----------+
|    1    |     rob     |   20    |      1      |       20      |     1    |
|    2    |     john    |   60    |      3      |       60      |     3    |
|    3    |     jane    |   0     |      0      |       0       |     0    |
|    4    |     mike    |   0     |      0      |       100     |     1    | 
+---------+-------------+-----------------------+---------------+----------+

这是我的查询:

SELECT
  u.*,
  COALESCE(sum(d.amount), 0) amount,
  COUNT(d.uid) monthly, 
  COUNT(d.amount) as Total, <-- need to get sum all time donations and number of times donated
FROM users u
LEFT JOIN donations d
  ON u.id = d.uid
    AND (month(d.date), year(d.date)) = (month(CURDATE()), year(CURDATE()))
GROUP BY u.id ORDER BY u.id ASC

所以我需要从相同的数据中添加 2 个不同的总和。

编辑:http://sqlfiddle.com/#!2/20a974/9架构和数据

我该怎么做？

Answer 1

为此，我们需要在 select 而不是 join 上过滤数据。

删除此条件:

AND (month(d.date), year(d.date)) = (month(CURDATE()), year(CURDATE()))

并将其添加到选择中:

SUM (CASE WHEN (month(d.date), year(d.date)) = (month(CURDATE()), year(CURDATE())) THEN 1 ELSE 0 END) as monthly

编辑:

整个查询:

SELECT users.id, users.username, 
  COALESCE(sum(CASE WHEN (month(donations.date), year(donations.date)) = (month(CURDATE()), year(CURDATE())) THEN donations.amount ELSE 0 END), 0) monthly_sum, 
  COALESCE(sum(CASE WHEN (month(donations.date), year(donations.date)) = (month(CURDATE()), year(CURDATE())) THEN 1 ELSE 0 END), 0) monthly_amount, 

  COALESCE(sum(donations.amount), 0) total_sum, 
  count(*) total_amount

from users
left join donations
  on donations.uid = users.id
group by users.id, users.username

http://sqlfiddle.com/#!2/20a974/20/0