DataTables("表A").datarows.clear
Dim lst As List(of String) = DataTables("表B").GetValues("姓名","姓名>''")
For Each s As String In DataTables("表C").GetValues("姓名","姓名>''")
If lst.Contains(s) = False Then lst.Add(s)
Next
For Each s As String In lst
Dim dr As DataRow = DataTables("表A").AddNew
dr("姓名") = s
dr("总分")= DataTables("表B").compute("sum(分数)" ," 姓名='" & s & "' ") + DataTables("表C").compute("sum(分数)" ," 姓名='" & s & "' ")
Next