MYSQL - 从两个表的 INNER JOIN 获取数据

Question

我有两个表用于获取印象并点击

Product
+----+--------+
| PID| brand  |
+----+--------+
|  1 | Ford   |
|  2 | Toyota |
|  6 | Holden |
+----+--------+

States
+----+--------+------+--------+------------+
| ID | PID    |CLICKS| VIEWS  | DATE       |
+----+--------+------+--------+------------+
|  1 | 1      |   1  |   0    |  12/12/2015|
|  1 | 1      |   1  |   0    |  12/12/2015|
|  2 | 2      |   1  |   0    |  12/12/2015|
|  3 | 2      |   0  |   1    |  12/12/2015|
|  3 | 1      |   0  |   1    |  12/12/2015|
+----+--------+------+--------+------------+

我需要得到这样的结果

+--------+------+--------+
| PID    |CLICKS| VIEWS  |
+--------+------+--------+
| 1      |   2  |   1    |
| 2      |   1  |   0    |
+--------+------+--------+

这可能吗？我已经尝试了太多次它即将出现的故障数据

Answer 1

SELECT
  PID,
  SUM(CLICKS) as CLICKS,
  SUM(VIEWS) as VIEWS
FROM States
GROUP BY PID

如果您的所有产品都需要 0

SELECT
  Products.PID,
  SUM(CLICKS) as CLICKS,
  SUM(VIEWS) as VIEWS
FROM Products 
     LEFT JOIN States ON States.PID=Products.PID
GROUP BY Products.PID