如何从同一个表中获取两个不同值的SUM [英] how to get SUM of two different values from same table

问题描述

大家好...



i希望从同一个表中得到SUM值，但在mysql中有两个不同的条件，示例表就在这里...

hi all...

i want get SUM of values from same table but two different conditions in mysql, the sample table is here...

 --------------------------------------
  credit_id | debit_id | Amount         
 --------------------------------------
|  1           4          10           |
|  1           3          10           |
|  1           2          10           |
|  2           1          20           |
|  3           1          20           |
|  5           1          20           |
----------------------------------------

step1：

首先得到 SUM（金额），其中credit_id =`1`;

结果是30.



step2：

第二次得到 SUM（金额）其中debit_id =`1`;

结果是60.



step3：

最后一步是 step2 - step1

即60-30 = 30.





如何在单个MySql查询中获得此结果..

请帮助我....

step1:
First get the SUM(Amount) where credit_id=`1`;
The result is 30.

step2:
Second get the SUM(Amount) where debit_id=`1`;
The result is 60.

step3:
The final step is step2 - step1
That is 60-30=30.


How to get this result in single MySql query..
please help me....

推荐答案

select (select sum(Amount) from table3 where debit_id ='1') - (select sum(Amount) from table3 where credit_id ='1') 

刚从慢跑回来，这里有一个快速解决方案：

Just back from a jog, a quick solution here:

select (select sum(amount) from table3 where credit_id ='5') -
(SELECT IF((select count(*) from table3 WHERE debit_id='5') > 0, (select sum(amount) from table3 where debit_id ='5'), 0))

这篇关于如何从同一个表中获取两个不同值的SUM的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！