重复了:

For Each nm() As String In dt1.GetValues("客户名称|年|月")
For Each nv() As String In dt2.GetValues("客户名称|年|月")
    Dim dr As Row = Tables("财务_Table1").AddNew()
    dr("客户名称") = nm(0)
    dr("年") = nm(1)
    dr("月") = nm(2)
    dr("实收金额") = dt1.Compute("Sum(实收金额)","客户名称 = \'" & nm(0) & "\'And [年] = \'" & nm(1) & "\'And [月] = \'" & nm(2) & "\'")
    dr("开票金额") = dt2.Compute("Sum(开票金额)","客户名称 = \'" & nv(0) & "\'And [年] = \'" & nv(1) & "\'And [月] = \'" & nv(2) & "\'")
    dr("开票税额") = dt2.Compute("Sum(开票税额)","客户名称 = \'" & nv(0) & "\'And [年] = \'" & nv(1) & "\'And [月] = \'" & nv(2) & "\'")
    dr("开票总额") = dt2.Compute("Sum(开票总额)","客户名称 = \'" & nv(0) & "\'And [年] = \'" & nv(1) & "\'And [月] = \'" & nv(2) & "\'")
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