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我把那些文件和其他文件都删了，只留狐表图标那个文件，这样再打开就可以了

运行下面的代码的时候，提示出错，是不是因为数据太多了，Exception has been thrown by the target of an invocation.

If e.DataCol.Name = "发货单号" Then

If e.NewValue Is Nothing Then

e.DataRow("付款金额") = Nothing

Else

Dim aa As DataRow

aa = DataTables("1流水").Find("[订单号] = '" & e.NewValue & "'")

If aa IsNot Nothing Then

e.DataRow("付款金额") = DataTables("1流水").Compute("sum(交易金额)","[订单号] = '" & e.NewValue & "'")

Else

Dim ab As DataRow

ab = DataTables("2流水").Find("[订单流水号] = '" & e.NewValue & "'")

If ab IsNot Nothing Then

e.DataRow("付款金额") = DataTables("2流水").Compute("sum(金额)","[订单流水号] = '" & e.NewValue & "'")

Else

Dim ac As DataRow

ac = DataTables("3流水").Find("[流水号] = '" & e.NewValue & "'")

If ac IsNot Nothing Then

e.DataRow("付款金额") = DataTables("3流水").Compute("sum(金额)","[流水号] = '" & e.NewValue & "'")

Else

Dim ad As DataRow

ad = DataTables("4流水").Find("[订单号] = '" & e.NewValue & "'")

If ad IsNot Nothing Then

e.DataRow("付款金额") = DataTables("4流水").Compute("sum(金额)","[订单号] = '" & e.NewValue & "'")

Else

e.DataRow("付款金额")= "-1000"

End If

应该是，代码本身看不出什么问题。

这种建议在数据库做一个查询表/视图，用于查询

select 订单号,金额 from (

select 订单号,sum(交易金额) as 金额, 1 as 序号 from 1流水 group by 订单号

union

select 订单流水号 as 订单号,sum(金额) as 金额, 2 as 序号 from 2流水 group by 订单流水号

union

select 流水号 as 订单号,sum(金额) as 金额, 3 as 序号 from 3流水 group by 流水号

union

select 订单号,sum(金额) as 金额, 4 as 序号 from 4流水 group by 订单号) as a where 金额 > 0 order by 序号

然后使用SQLCommand获取金额

Dim val As double
Dim cmd As New SQLCommand
cmd.ConnectionName = "数据源名称"
cmd.CommandText = "Select top 1 * From {某视图} Where 订单号 ='" & e.NewValue & "'"

val = cmd.ExecuteScalar()

if val = 0 then val = -1000

e.DataRow("付款金额")=val

你好，请教一下，如果数据庞大，链接SQL2005是不是会好点，现在四五个表，一个表十几万条，有时候再导入数据就提示错误

数据量大SqlServer肯定比access好。

另外数据库优化可以看看：http://www.foxtable.com/bbs/dispbbs.asp?BoardID=2&ID=158943&replyID=&skin=1

那调用外部数据，这样就需要设置窗口和菜单来配合使用才可以是吧

也可以在表事件处理的。数据量多的，还是学学sql的用法吧

从哪章看是看起会好点呀

用变事件处理，是不是还是要把数据直接导入到狐表，还是说在狐表里面的事件处理根据条件调用出来？

主题：Exception has been thrown by the target of an invocation.