Question

这是我创建的sql

SELECT SUM(SupplierItems.SupplierItemCost +
           SupplierItems.SupplierItemInventory
          ) AS TotalCost
FROM SupplierItems 
GROUP BY SupplierItems.ID

上面的sql获取两个字段的总和，即itemcost和iteminventory，这就是结果

TotalCost
1000
2000
3000

我需要从TotalCost获取所有的总和。

谢谢

Answer 1

如果要在表中显示总计，请删除GROUP BY：

SELECT SUM(si.SupplierItemCost +
           si.SupplierItemInventory
          ) AS TotalCost
FROM SupplierItems si;

但是要小心。如果任何基础值是NULL，则可能无法获得正确的结果。这样做更安全：

SELECT (COALESCE(SUM(si.SupplierItemCost), 0) +
        COALESCE(SUM(si.SupplierItemInventory, 0)
       ) AS TotalCost
FROM SupplierItems si;

Answer 2

如果要总计，则可以不使用 GROUP BY

SELECT SUM(SupplierItems.SupplierItemCost +
           SupplierItems.SupplierItemInventory
          ) AS TotalCost
FROM SupplierItems

如果要基于 SupplierItems.ID 进行部分总计，则可以使用 GROUP BY

SELECT SupplierItems.ID,SUM(SupplierItems.SupplierItemCost +
           SupplierItems.SupplierItemInventory
          ) AS TotalCost
FROM SupplierItems 
GROUP BY SupplierItems.ID

Answer 3

如果要在其他行中查看所有TotalCost的总和，则可以使用ROLLUP。

SELECT SupplierItems.ID, SUM(SupplierItems.SupplierItemCost +
           SupplierItems.SupplierItemInventory
          ) AS TotalCost
FROM SupplierItems 
GROUP BY ROLLUP(SupplierItems.ID)

如何使用SQL从2个字段的总和中获取总计？

3 个答案: