MYSQL具有唯一结果的列的求和

我有一张多对多的桌子

+----------+-----------+-----------+
|   p      |    t      |   weight  |
+----------+-----------+-----------+
|   1      |   bob     |    40     |
+----------+-----------+-----------+
|   2      |   sue     |    24     |
+----------+-----------+-----------+
|   3      |   bob     |    90     |
+----------+-----------+-----------+
|   4      |   joe     |    55     |
+----------+-----------+-----------+
|   5      |   bob     |    33     |
+----------+-----------+-----------+

我想查询t值，其中p在（1,2,4,5）中，同时求和t的每个值的权重

此查询：

“选择t，总和（权重）作为从p_到p_t的方向，其中p位于（1,2,4,5）”仅将所有总和添加到选定的第一个“t”中，例如

+-----------+-----------+
|    t      |   weight  |
+-----------+-----------+
|   bob     |   152     |
+-----------+-----------+

我想要的是：

+-----------+-----------+
|    t      |   weight  |
+-----------+-----------+
|   bob     |   97      |
+-----------+-----------+
|   joe     |   55      |
+-----------+-----------+

想法
 只需在t上添加一个
groupby
子句即可

SELECT 
 t, 
 SUM(weight) AS sWeight 
FROM p_to_t 
WHERE p IN(1,2,4,5)
GROUP BY t

顺便说一下，您还可以在in子句中使用这些值获取Sue

对于Bob来说不是
97
，因为
40+33
通常是
73
只需在t上添加一个
GROUP BY
子句即可

SELECT 
 t, 
 SUM(weight) AS sWeight 
FROM p_to_t 
WHERE p IN(1,2,4,5)
GROUP BY t

SELECT t, SUM(weight) AS sWeight FROM p_to_t WHERE p IN(1,2,4,5) GROUP BY t

顺便说一下，您还可以在in子句中使用这些值获取Sue

对于Bob来说不是
97
，因为
40+33
通常是
73

SELECT t, SUM(weight) AS sWeight FROM p_to_t WHERE p IN(1,2,4,5) GROUP BY t


是的，您可以在实际查询中仅添加Group by。然后您将得到以下结果

SELECT t, SUM(weight) AS sWeight 
 FROM p_to_t 
WHERE p IN(1,2,4,5)
Group by t;

+-----------+-----------+
|    t      |   weight  |
+-----------+-----------+
|   bob     |   73      |
+-----------+-----------+
|   joe     |   55      |
+-----------+-----------+
|   sue     |   24      |
+-----------+-----------+

是的，您可以在实际查询中仅添加分组依据。然后您将得到以下结果

SELECT t, SUM(weight) AS sWeight 
 FROM p_to_t 
WHERE p IN(1,2,4,5)
Group by t;

+-----------+-----------+
|    t      |   weight  |
+-----------+-----------+
|   bob     |   73      |
+-----------+-----------+
|   joe     |   55      |
+-----------+-----------+
|   sue     |   24      |
+-----------+-----------+

太好了，谢谢。是的，我忘记了苏，把她的观点加在了鲍勃身上。对不起，苏。@HowardZoopalopa苏会原谅的。太好了，谢谢。是的，我忘记了苏，把她的观点加在了鲍勃身上。对不起，苏。@HowardZoopalopa苏会原谅的。