Reasking the same question below that some else asked in 2016 from here https://www.telerik.com/forums/expressionbuilder-expression(filters)-in-kendo-mvc-grid-not-working-for-navigation-collection
Is this still the same answer 5 years on?
Original Question from 2016
"We are using Kendo MVC Grid in our application. We are using LINQ to EF to query the tables.
Following is a query in our application:
This works fine as long as the filters are any columns from the "ParentTable". However, the ParentTable has a navigation collection ICollection<ChildTable> and the ChildTable has a property ChildProperty and the method ExpressionBuilder.Expression fails when we use this ChildProperty for filtering.
Any solution for this problem?
I'm copying my reply to your support ticket here for customer reference.
I'm afraid the Where extension does not support filtering by collection.
This is not a design goal of the data engine.