Can't have DataField with Join, a GridCalculatedColumn, and Filtering all in one

[Andrew]

I'm trying to fix up a page so that the RadGrid has working filters. This has been fine on other pages, but the presence of a GridBoundColumn with a join in the DataField, and a GridCalculatedColumn is making this difficult.

My findings:
 - Originally, EnableLinqExpressions ("ELE") was set to "false", but this meant that filtering didn't work
 - ELE = false and removing the Calculated field --> Filtering works
 - ELE = false and removing the Joined filed --> Filtering is broken
 - ELE = true --> I get a Telerik.Web.UI.ParseException: ')' or ',' expected. No clear column as the culprit, error seems derived from the GridyDynamicQueryable.Select()
 - ELE = true and removing Calculated field --> Filtering works
 - ELE = true and removing Joined field --> Filtering works

And my boiled-down code:

<telerik:RadGrid ID="rgdInvoices" runat="server" DataSourceID="ldsInvoices" AutoGenerateColumns="false"
    AllowFilteringByColumn="true" EnableLinqExpressions="true" ShowFooter="true">
        <MasterTableView DataKeyNames="InvoiceID" EditMode="InPlace">
            <Columns>
                <telerik:GridBoundColumn UniqueName="BookingName" DataField="WEB_Booking.JobName" HeaderText="Job Name"
                    AutoPostBackOnFilter="true" ShowFilterIcon="false" />

                <telerik:GridNumericColumn UniqueName="SubTotal" DataField="SubTotal" ReadOnly="true"
                    HeaderText="Sub Total" NumericType="Currency" FilterControlWidth="120px"
                    Aggregate="Sum" FooterAggregateFormatString="{0:c}" />

                <telerik:GridCalculatedColumn UniqueName="GST" HeaderText="GST" DataType="System.Decimal"
                    DataFormatString="{0:c}" DataFields="SubTotal" Expression="{0}*0.1" Aggregate="Sum"
                    FooterAggregateFormatString="{0:c}" />
            </Columns>
        </MasterTableView>
    </telerik:RadGrid>

It seems to me that there's an error with the code of a filtering function when a Join and Calculated field are being used. I also don't want to have to denormalise my database, but if I can't find a resolution soon, I'll have to do that.

[Pavlina]

Hi Andrew,

The following forum thread elaborates on a similar problem and a sample projects with GridCalculatedColumn are also attached in it:
http://www.telerik.com/forums/gridcalculatedcolumn-and-enablelinqexpressions-false-cause-exception

Give them a try and let me know if they help.

Regards,
Pavlina
Telerik