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    <p>This seems to be a limitation in the current version of Entity Framework (1.0) Have a look at <a href="https://stackoverflow.com/questions/944332/entity-framework-inheritance-and-include">this related SO question</a>.</p> <p>In your case including the related <strong>UserCreated</strong> and <strong>UserEdited</strong> properties in the projection is the right solution. However if you also want to populate the <strong>Image</strong> property on the <strong>UserSpecial</strong> object, you must be sure to include that as well:</p> <pre><code>var results = from articleSpecial in ctx.ArticleBase.OfType&lt;ArticleSpecial&gt;() select new { articleSpecial, articleSpecial.UserCreated, ((UserSpecial)articleSpecial.UserCreated).Image, articleSpecial.UserEdited, ((UserSpecial)articleSpecial.UserEdited).Image }; </code></pre> <p>Of course this query builds on the assumption that <strong>all ArticleSpecial entities always refer to a UserSpecial entity</strong>, otherwise the casting will fail.<br/> If this assumption isn't always true, you could express the same query using the LINQ extension methods and a multi-line lambda function to perform a safe casting:</p> <pre><code>var results = ctx.ArticleBase .OfType&lt;ArticleSpecial&gt;() .AsEnumerable() .Select(a =&gt; { var userCreated = a.UserCreated as UserSpecial; if (userCreated != null) { var image = userCreated.Image; } var userEdited = a.UserEdited as UserSpecial; if (userEdited != null) { var image = userEdited.Image; } return a; }); </code></pre> <p>In the latter example, you also do not need to include <strong>UserSpecial</strong> and <strong>Image</strong> entities in the results. Instead you just need to access the navigation properties on the <strong>ArticleSpecial</strong> entities during the projection phase in order to force Entity Framework to eager load the related objects. </p>
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    1. COI'm trying to do this same thing but I'm confused because there is no "UserCreated" in the model pictured in the question. Where is that coming from?
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    2. COAlso, the second option with the multiline lambda gives me an error indicating it cannot be converted to an expression tree. See: http://weblogs.asp.net/zeeshanhirani/archive/2008/07/10/not-all-lambdas-can-be-converted-to-expression-trees.aspx
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    3. CO@AaronLS I believe that "UserCreated" and "UserEdited" are really the navigation properties "CreatedBy" and "EditedBy" pictured in the model. They have probably been renamed :-)
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