SQL查詢使用Sum（）連接兩個查詢

Question

我知道這對您的sql人員來說很簡單，但是我試圖將兩個簡單的查詢合並為一個。 從代碼中可以明顯看出job.ActiveJob.ID = job.EstimateTbl.ID_Job。

我正在嘗試獲取：id，JobName，sum（itemAmount）

謝謝你的幫助。

SELECT a.id, a.JobName
FROM job.ActiveJobsTbl AS a
WHERE a.ID = '100' 

SELECT SUM(itemAmount)
FROM job.EstimateTbl
WHERE ID_Job = '100'

Answer 1

您可以通過ON E.ID_Job = A.ID JOIN表，並使用GROUP BY獲取SELECT的值

SELECT A.id, A.JobName, SUM(E.itemAmount) AS Amount 
FROM job.ActiveJobsTbl AS A
INNER JOIN job.EstimateTbl E ON E.ID_Job = A.ID 
WHERE A.ID = '100'  
GROUP BY A.id, A.JobName;

Answer 2

使用LEFT JOIN

SELECT a.id, a.JobName,EstimateTbl.itemAmount
FROM job.ActiveJobsTbl AS a
left join
( 
    SELECT SUM(itemAmount) itemAmount,ID_Job
    FROM job.EstimateTbl
    group by ID_Job
) EstimateTbl on  EstimateTbl.ID_Job = a.ID
WHERE a.ID = '100' 

Answer 3

您可以使用APPLY ：

select a.id, a.JobName, t.itemAmount 
from job.ActiveJobsTbl AS a OUTER APPLY
     (SELECT SUM(t.itemAmount) AS itemAmount
      FROM job.EstimateTbl AS t
      WHERE t.ID_Job = a.ID
     ) t
WHERE a.ID = 100; 

Answer 4

嘗試這個：

SELECT A.id, A.JobName, SUM(E.itemAmount) AS Amount 
FROM job.ActiveJobsTbl AS A
INNER JOIN job.EstimateTbl E ON E.ID_Job = A.ID 
WHERE A.ID = '100'
GROUP BY A.id, A.JobName;