Unable to create a constant value of type (type) Only primitive types ('such as Int32, String, and Guid') are supported in this context

Question

I\'ve read ALL of:

• Unable to create a constant value of type 'System.Object' in Entity Framework

• Entity Framework - "Unable to

Answer 1

It will not work because you want to use local Album in linq-to-entities query. You must either use navigation property on p to get its album:

var query = from p in VisibleObjects.OfType()
            where p.Album.Id == alb.Id
            select p;

or you must build complex query with some join between photos and albums. You cannot pass local object and any its relation to the query. Only simple properties can be passed.