"Cannot find column" when sorting dynamically filled grid

[Alexander]

Hi, I fill RadGrid in NeedDataSource like this:

protected void rgPortConfigView_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
{
    var grid = (RadGrid) sender;

    IList<Swfc_Port_ConfigInfo> lpi;
    var spc = new Swfc_Port_Config_StateController();
    var dateRange = B4DateTimePicker.DateFromDateToFromPickerOrDefault(Page, "B4DateTimePickerDatesFilter", DateTime.Now.AddDays(-6), DateTime.Now, UrlConst.DATE_FROM, UrlConst.DATE_TO);
    this.dateFrom = dateRange.DateFrom;
    this.dateTo = dateRange.DateTo;

    int sfSanSwitchId;
    if (int.TryParse(Request.QueryString[UrlConst.SF__SAN_SWITCH__ID], out sfSanSwitchId))
    {
        QueryParams.SetValue("SAN_SWITCH_ID", sfSanSwitchId, FilterCondition.Equal, false);
    }
    int sfSwfcPortConfigSwfcPortIndex;
    if (int.TryParse(Request.QueryString[UrlConst.SF__SWFC_PORT_CONFIG__SWFC_PORT_INDEX], out sfSwfcPortConfigSwfcPortIndex))
    {
        QueryParams.SetValue("SWFC_PORT_INDEX", sfSwfcPortConfigSwfcPortIndex, FilterCondition.Equal, false);
    }

    switch (SubTabID)
    {
        case "top20ports":
            lpi = spc.LoadForPerformance(0, 20, "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
        case "allports":
            lpi = spc.LoadForPerformance(0, Int32.MaxValue - 2, grid.MasterTableView.SortExpressions.GetSortString() ?? "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
        case "top10isl":
            lpi = spc.LoadForPerformanceISL(0, 10, "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
        case "top20isl":
            lpi = spc.LoadForPerformanceISL(0, 20, "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
        case "allisl":
            lpi = spc.LoadForPerformanceISL(0, Int32.MaxValue - 2, grid.MasterTableView.SortExpressions.GetSortString() ?? "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
        case "top10ports":
        default:
            lpi = spc.LoadForPerformance(0, 10, "PERFORMANCE_IOSUM DESC", this.dateFrom, this.dateTo);
            this.rgPortConfigView.DataSource = lpi;
            break;
    }

    QueryParams.Remove("SAN_SWITCH_ID");
    QueryParams.Remove("SWFC_PORT_INDEX");
}

Here is one of the columns that causes the mentioned exception:

<telerik:GridTemplateColumn HeaderStyle-CssClass='GridHeaderGreen la' ItemStyle-CssClass='la' UniqueName="San_Switch__DisplayName" HeaderText="Switch Name" SortExpression="SAN_SWITCH_NAME">
    <ItemTemplate>
        <asp:HyperLink ID="hlSwitchName" runat="server" Text='<%# Eval("San_Switch.DisplayName") %>' NavigateUrl='<%# GetUrlToSwitchInfo(Container.DataItem) %>' />
    </ItemTemplate>
</telerik:GridTemplateColumn>

The funny thing is that db data is returned properly from LoadForPerformance method! And there is no error in SQL part! The exception happens AFTER! The grids with using "static" ObjectDataSource work without any problem in such cases, i.e. I can indicate field names or full names, using DB schema, table name and column name like SortExpression="SF.SAN_SWITCH.NAME"...

[Alexander]

Oops, forgot to use

AllowCustomSorting="True"

Now it works properly :)