从表单价和数量引发主表的总价变化

use CNDatagoCreate Trigger AddPriceON dbo.Te_PurchaseaAFTER INSERTASUPDATE dbo.Te_PurchaseSET Sum_Price = Sum_Price + inserted.Price * inserted.Req_Pur_Qtyfrom inserted,Te_Purchasewhere inserted.Pur_No = Te_Purchase.Pur_NogoCreate Trigger UpdatePriceON dbo.Te_PurchaseaAFTER UPDATEASif(UPDATE(Price) OR UPDATE(Req_Pur_Qty))begin  UPDATE dbo.Te_Purchase  SET Sum_Price = 0  from inserted  where inserted.Pur_No = Te_Purchase.Pur_No    UPDATE dbo.Te_Purchase  SET Sum_Price = Sum_Price + Te_Purchasea.Price * Te_Purchasea.Req_Pur_Qty  from inserted,Te_Purchasea  where inserted.Pur_No = Te_Purchase.Pur_No        and inserted.Pur_No = Te_Purchasea.Pur_Noendgo

简单思路 :  插入直接累加就好了 如果是更新就要先清空再重新计算