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Exceptional loading of multiple items

So, according to this page , the Entity Framework should look forward to loading multiple layers using Selectin method Include.

I have the following code:

var reports = _context.Reports
    .Include(rt => rt.Fields)
    .Include(rt => rt.Fields.Select(f => f.FieldType))
    .Include(rt => rt.Fields.Select(f => f.FieldType.FieldIdentifier));

However, this causes InvalidOperationException“Invalid expression type” when invoking the second include. The exception comes from EntityFrameworkHelper.CollectRelationalMemebers.

I also tried using strings for Includerelated properties, but that also failed (I would prefer to avoid using strings, if at all possible).

I am using the EF 5.0 DLL for .NET 4.0. My EF classes are old fashioned databases - first EntityObjects.

Does anyone know the reason and can I do anything with this exception?

EDIT:

When using the string version:

var reports = _context.Reports
    .Include("Fields")
    .Include("Fields.FieldType")
    .Include("Fields.FieldType.FieldIdentifier"));

InvalidOperationException - .

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, Include DLL, , Entity Framework Include. . .

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. , - . :

var reports = _context.Reports
    .Include(rt => rt.Fields.Select(f => f.FieldType.FieldIdentifier));
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