Question

我有2个表FinalList和RemoveTheseIDsList。它们都具有ID的相同主键。我想删除FinalList中RemoveTheseIDsList的所有行。所以，我写了第一个问题：

Delete from FinalList
    Where FinalList.ID not in (Select ID from RemoveTheseIDsList)

理论上，该查询应删除FinalList中的每一行。相反，它删除了0.我最终确定了这个笨重的解决方法（确实有效）：

Update FinalList set DeleteMe='Y'
    from FinalList FLL
    left join RemoveTheseIDsList REM on FLL.ID=REM.ID
    where REM.ID is null
Delete from FinalList where DeleteMe='Y'

我的问题是：为什么第一个查询不起作用？是否有一个快速解决方案，可以保持此查询既可用又小？

Answer 1

正如你所说：“我想从FinalList 中删除所有 RemoveTheseIDsList”中的记录

所以它应该是：

Delete from FinalList
Where FinalList.ID IN (Select ID from RemoveTheseIDsList)

但是你的更新就像不在，所以也许试试这个：

Delete from FinalList
Where FinalList.ID NOT IN (Select RemoveTheseIDsList.ID from RemoveTheseIDsList)

SQL Server：为什么这个Delete查询不起作用？

1 个答案: