Question

我想知道是否有办法找到已计算的派生列的总和到新列中。

Employee_KT_State
--------------------------------------------------------
Emp_Id      Team           KT_State            Left_Org
----------------------------------------------------------
 101        Orange         In Progress          2016
 102        Red            Complete             2016
 103        Orange         Complete             N
 104        Green          In Progress          N
 105        Orange         Not Started          N
 106        Green          Not Started          2015
 107        Red            In Progress          N
 108        Red            Complete             N
 109        Green          Complete             N
-----------------------------------------------------------

SELECT
  SUM(if (KT_State = 'In Progress' AND Team = 'Red', 1, 0)) AS 'Red In Progress Count',
  SUM(if (KT_State = 'In Progress' AND Team = 'Green', 1, 0)) AS 'Green In Progress Count',
  SUM(if (KT_State = 'In Progress' AND Team = 'Orange', 1, 0)) AS 'Orange In Progress Count'
   SUM(if (KT_State = 'Complete' AND Team = 'Green', 1, 0)) AS 'Green Complete Count'
    FROM 
       Employee_KT_State

我试图添加绿色进行中和完成计数。我可以直接使用从第2和第4列派生的计数，而不是使用具有不同if条件的另一个SUM吗？

 something like - 

  SELECT
   SUM(if (KT_State = 'In Progress' AND Team = 'Red', 1, 0)) AS 'Red In Progress Count',
   SUM(if (KT_State = 'In Progress' AND Team = 'Green', 1, 0)) AS 'Green In Progress Count',
   SUM(if (KT_State = 'In Progress' AND Team = 'Orange', 1, 0)) AS 'Orange In Progress Count'
   SUM(if (KT_State = 'Complete' AND Team = 'Green', 1, 0)) AS 'Green Complete Count',
   'Green In Progress Count' + 'Green Complete Count' AS ' Green In-Progress and Complete Count'   --> Will this yield me results??
    FROM 
       Employee_KT_State

感谢任何帮助。

Answer 1

在MySQL中，您可以将代码简化为：

SELECT SUM(KT_State = 'In Progress' AND Team = 'Red') AS `Red In Progress Count`,
       SUM(KT_State = 'In Progress' AND Team = 'Green') AS `Green In Progress Count`,
       SUM(KT_State = 'In Progress' AND Team = 'Orange') AS `Orange In Progress Count`,
       SUM(KT_State = 'Complete' AND Team = 'Green') AS `Green Complete Count`,
FROM Employee_KT_State;

要获得两个额外的列，您需要明确拥有SUM()表达式。

请注意，我更改了列名以使用列别名的反引号。仅对字符串和日期常量使用单引号。

Answer 2

使用子查询

SELECT t.*,
       `Green In Progress Count` + `Green Complete Count` 
          As ` Green In-Progress and Complete Count`
FROM (
     SELECT x As `Green In Progress Count`,
            2* x As `Green Complete Count`
     FROM Employee_KT_State
) t

| Green In Progress Count | Green Complete Count | Green In-Progress and Complete Count |
|-------------------------|----------------------|--------------------------------------|
|                       1 |                    2 |                                    3 |
|                       2 |                    4 |                                    6 |
|                       3 |                    6 |                                    9 |

简化演示：http://sqlfiddle.com/#!9/b7ddd8c/2

apollo-angular

计算几个派生列的SUM总和

2 个答案: