主题：如何加载按月新生成的和以前月生成的表中的数据到一个总的记录表中？

编码错误：'Select Case' must end with a matching'End Select'
Select*From{Tab_P_ProductRecord201011} Into {_Tab_P_ProductRecord2010}

晕，你将这个作为代码使用？

这是SQL语句，应该用SQLCommand来执行的。

Dim cmd As New SQLCommand
Dim dt As DataTable
cmd.C
cmd.CommandText = "Select*From{Tab_P_ProductRecord201011} Into {_Tab_P_ProductRecord2010}"
dt = cmd.ExecuteReader()
For Each dr As DataRow In dt.DataRows
    If DataTables("Tab_P_ProductRecord201011").Find("ID = '" & dr("ID") & "'") Is Nothing Then
        Dim nr As DataRow = DataTables("Tab_P_ProductRecord201011").AddNew()
        For Each dc As DataCol In dt.DataCols
            nr(dc.name) = dr(dc.name)
        Next
    End If
Next

 

 

代码执行出错，错误信息：
System.NullReferenceException:Object reference not set to an instance of an object  at UserCode.Test()

错误代码位置;窗口5，Button4,Click
System.NullReferenceException:Object reference not set to an instance of an object  at UserCode.Click_2df1b3cf(ControlEventArgs e)

找到行才执行，所以应该:

 

 If DataTables("Tab_P_ProductRecord201011").Find("ID = '" & dr("ID") & "'") IsNot Nothing Then

Dim cmd As New SQLCommand

Dim dt As DataTable

cmd.ConnectionName = "AsiaCardServer"23楼时粘贴时遗漏，不好意思

cmd.CommandText = "Select*From{Tab_P_ProductRecord201011} Into {_Tab_P_ProductRecord2010}"

dt = cmd.ExecuteReader()

For Each dr As DataRow In dt.DataRows

If DataTables("Tab_P_ProductRecord201011").Find("ID = '" & dr("ID") & "'") IsNot Nothing Then

Dim nr As DataRow = DataTables("Tab_P_ProductRecord201011").AddNew()

For Each dc As DataCol In dt.DataCols

nr(dc.name) = dr(dc.name)

Next

End If

Next

依然是：

代码执行出错，错误信息：
System.NullReferenceException:Object reference not set to an instance of an object  at UserCode.Test()

错误代码位置;窗口5，Button4,Click
System.NullReferenceException:Object reference not set to an instance of an object  at UserCode.Click_2df1b3cf(ControlEventArgs e)

你的代码是不对的，下面的语句:
 
Select * From{Tab_P_ProductRecord201011} Into {_Tab_P_ProductRecord2010}
 
并不是一个查询语句，而是一个操作语句，直接在后台将前面表的内容合并到后面的表，所以不会返回一个DataTable。
 
大概的代码应该是：
 
Dim cmd As New SQLCommand
cmd.Connection Name = "AsiaCardServer"
cmd.CommandText = "Select * From {Tab_P_ProductRecord201011} Into {_Tab_P_ProductRecord2010}"
cmd.ExecuteNonQuery()
 
这样就完成了合并，你可以加载第二个表查看合并结果。