Question

我有两张表来获得展示，然后点击

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|
+----+--------+------+--------+------------+

我需要得到一些像这样的结果

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

有可能吗？我已经尝试过多次未来的故障数据

Answer 1

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

如果所有产品需要0

- (CGFloat)carouselItemWidth:(iCarousel *)carousel
{
    //usually this should be slightly wider than the item views
    return 240;
}

Answer 2

通过Inner Join使用它。

SELECT t1.pid, sum(clicks) as CLICKS, sum(views) as VIEWS
FROM Product as t1 INNER JOIN States as t2 ON t1.pid=t2.pid GROUP BY t1.pid

MYSQL - 使用两个表从INNER JOIN获取数据

2 个答案: