如何在 SQL 中取一个总和？

Question

我有以下数据，我需要得到一个总和。

项目编号	Work_Order_Number	数量
X-1	11	10
X-1	11	10
X-1	11	10
X-1	121	15
X-1	121	15
X-1	121	15
X-1	131	20
X-1	131	20
X-1	131	20

这个数据的问题是重复。

我使用以下代码对其进行了一些清理。

SELECT 
    Item_Number,
    Work_Order_Number,
    SUM(Qty) AS QTY,
    COUNT(Work_Order_ID) AS Count
FROM table
WHERE Item_Number = 'X-1' 
GROUP BY Item_Number, Work_Order_Number

要获得以下信息：

项目编号	Work_Order_Number	数量	数数
X-1	11	30	3
X-1	121	45	3
X-1	131	60	3

如何更改代码以获得以下内容：

项目编号	总数（量
X-1	45

我试过用这个：

SELECT 
    Item_Number,
    Work_Order_Number,
    SUM(Qty) AS QTY,
    COUNT(Work_Order_ID) AS Count
    SUM(SUM(Qty)/COUNT(Work_Order_ID)) AS Total_Quantity
FROM table1
WHERE Item_Number = 'X-1' 
GROUP BY Item_Number

Answer 1

我知道你想得到一列的总数，如果是这样，这里是查询。 SELECT SUM(Qty) AS totalQuantiy FROM table1; 如果数据类型是 Varchar，则使用 COUNT function。

Answer 2

对我来说，您似乎想要总平均数量。

 SELECT Item_Number, SUM(AverageQuantity) AS Total_Quantity FROM ( SELECT Item_Number, Work_Order_Number, AVG(Qty) AS AverageQuantity FROM table1 WHERE Item_Number = 'X-1' GROUP BY Item_Number, Work_Order_Number ) q GROUP BY Item_Number

项目编号	总数（量
X-1	45.0000

db<> 在这里摆弄

Answer 3

SELECT Item_Number,
       SUM(QTY) / COUNT(Item_Number) AS Total_Quantity
FROM
  (SELECT 
      Item_Number,
      SUM(Qty) AS QTY
  FROM table
  WHERE Item_Number = 'X-1' 
  GROUP BY Item_Number, Work_Order_Number) T
GROUP BY Item_Number