关于查询库存流水帐的高难度问题

我在你写的查询基础上，加了个判断函数，则解决问题。

具体语句如下：

SELECT NEWKU.序号, NEWKU.异动日期, NEWKU.料号, NEWKU.入仓, NEWKU.出仓, DSum("余额","流水结存","[异动日期]<=" & "#" & [异动日期] & "# and [料号]='" & [料号] & "'") AS 结存, IIf(IsNull(DSum("余额","流水结存","[异动日期]<" & "#" & [异动日期] & "# and [料号]='" & [料号] & "'")),0,DSum("余额","流水结存","[异动日期]<" & "#" & [异动日期] & "# and [料号]='" & [料号] & "'")) AS 库存, NEWKU.库位, [入仓]-[出仓] AS 余额
FROM NEWKU;

说明：

1、加个IIF判断函数；用ISNULL（）函数判断首条记录为空时，则期初库存为0

2、没必要用VAL（）函数。

详见附件