聚合可能不会出现在WHERE子句中（MSSM工作室）

Question

我正在尝试在广告表上创建插入的触发器。尝试编写此光标时

declare Users cursor for 
    Select "User".IDUser, Sum(Price)   
    from "User"
    inner join Purchase as pu on "User".IDUser = pu.IDUser  
    inner join PurchaseProduct as pp on pu.IDPurchase = pp.IDPurchase
    inner join Product as pr on pp.IDProduct = pr.IDProduct
    inner join inserted on pr.IDProduct = inserted.IDProduct
    where pr.ProductType = (select ProductType 
                            from Product
                            inner join Advertisement on Product.IDProduct = Advertisement.IDProduct
                            inner join inserted on Advertisement.IDProduct = inserted.IDProduct
                            where Advertisement.IDAdvertisement = inserted.IDAdvertisement)
      and Sum(Price) > 50;

我收到此错误

  

Msg 147，Level 15，State 1，Procedure AutomaticUserAdvertisementScoreCalculating，Line 15 [Batch Start line 113]
  聚合可能不会出现在WHERE子句中，除非它位于HAVING子句或选择列表中包含的子查询中，并且要聚合的列是外部引用。

这里可能出现的错误是什么？您可以在下面看到我的数据库结构

提前致谢

Answer 1

您可以使用HAVING在聚合后过滤行：

declare Users cursor for 
Select "User".IDUser, Sum(Price) from "User"
join Purchase as pu on "User".IDUser = pu.IDUser  
join PurchaseProduct as pp on pu.IDPurchase = pp.IDPurchase
join Product as pr on pp.IDProduct = pr.IDProduct
join inserted on pr.IDProduct = inserted.IDProduct
where pr.ProductType = (select ProductType from Product
              join Advertisement on Product.IDProduct = Advertisement.IDProduct
              join inserted on Advertisement.IDProduct = inserted.IDProduct
              where Advertisement.IDAdvertisement = inserted.IDAdvertisement)
GROUP BY "User".IDUser
HAVING Sum(Price) > 50;