为什么导入EXCEL数据到SQL数据库中，数据表总是有和记录个数一样多的空记录？望高手们指教

Public Sub in_from_excel(ByVal database_name As String, ByVal table_name As String, ByVal field_list_name As   String, ByVal excel_file As String)

        connectionstring = "data source=" & hostname & "/数据库名" & ";Initial Catalog=" & database_name & "                 ;User      Id=sa;Password=123;"
                        conn = New SqlConnection(connectionstring)
                               If conn.State = ConnectionState.Open Then
                       conn.Close()
                      End If
           'conn.ConnectionString = connectionstring
         conn.Open()

        ' sql = "INSERT INTO   " & table_name & "( ID, 凭证编号,生产编号,订单号,规格,颜色,米数,下单日期) " & "  SELECT             ltrim        (rtrim(ID)), ltrim(rtrim(凭证编号)),ltrim(rtrim(生产编号)),ltrim(rtrim(订单号)),ltrim(rtrim(规格)),ltrim(rtrim(颜色)),convert(int,米数) as 米数,convert(datetime,下单日期) as 下单日期  FROM  OPENROWSET( 'MICROSOFT.JET.OLEDB.4.0',' Excel 8.0;HDR=YES;DATABASE=" & excel_file & "'" & ", sheet1$')"
           Try
        cmd = New SqlCommand(sql, conn)
        cmd.ExecuteNonQuery()

         Catch ex As Exception
        ex.ToString()

        'End Try
end sub