sql - 更新Sql计算语句

Question

我可以知道如何更新 Sql Calculation 语句吗？

例如，我想将总和更新到表格

下面是代码

 SELECT p.Qty AS pQty,
       SUM(t.Qty) AS tQty,
       p.Qty - SUM(t.Qty) AS total ,
       p.PName
FROM tblTempTransaction t ,
     tblProducts p
WHERE t.UserID= 2
  AND t.OrderID=1
  AND p.pid = t.pid
GROUP BY t.UserID,
         p.qty ,
         p.PName ,
         t.OrderID

UPDATE tblProducts
SET qty = p.Qty - SUM(t.Qty)
WHERE t.UserID= 2
  AND t.OrderID=1
  AND p.pid = t.pid
GROUP BY t.UserID,
         p.qty ,
         p.PName ,
         t.OrderID

我将从 set qty = p.Qty - SUM(t.Qty) 中得到错误

我可以知道如何解决这个问题吗？谢谢。

Answer 1

假设您的查询是正确的..您忘记输入“来自”

  UPDATE tblProducts
     SET qty = p.Qty - sq.total from (select SUM(t.Qty) as total from "table" as t
   WHERE t.UserID= 2 and t.OrderID=1 and p.pid = t.pid
GROUP BY t.UserID, p.qty ,p.PName ,t.OrderID) as sq