如何在两个表中比较db2中的数据

Question

 update  StoreStock 
 set QTY = QTY + $QTY 
 where whStock.QTY >= $QTY
 and StoreStock.PNR = '$prod'"

我将如何运行此错误 我所拥有的是，whStock表的外键是Products表和StockStock外键是whStock

Answer 1

据我了解，您需要在Products表更新期间检查StockStock表中的条件。

假设StockStock表的外键whStock引用ID表中的Products列

update  StoreStock s
   set QTY = QTY + $QTY 
 where exists (select 1 from Products p where p.ID = s.whStock and p.QTY >= $QTY)
   and s.PNR = '$prod'