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POLINQ many-to-many intersection
 

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    <p>I'm trying to query <code>Posts</code> based on a list of <code>Tags</code>:</p> <pre><code>public class Post { public int? Id {get;set;} public string Name {get;set;} public virtual ICollection&lt;Tag&gt; Tags {get;set;} } public class Tag { public int? Id {get;set;} public string Name {get;set;} public vritual ICollection&lt;Post&gt; Posts {get;set;} } </code></pre> <p>Now I want to return posts based a list of tags: <code>IList&lt;Tag&gt; searchTags = ParseTagsFromSearchString("tag1,tag2,tag3"); // this function checks the tags in the database, so all the primary keys are available in the list</code></p> <p>When a post contains one or more tags that also exists in <code>searchTags</code> it should be included in the result. I have tried the following:</p> <pre><code>var q = from s in Context.Registrations where s.Tags.Intersect(tagList) select s; </code></pre> <p>Error: <code>Cannot implicitly convert type 'System.Collections.Generic.IEnumerable&lt;Models.Tag&gt;' to 'bool'</code></p> <pre><code>var q = from s in Context.Registrations where s.Tags.Any(t =&gt; tagList.Any(t2 =&gt; t.Id.Value == t2.Id.Value)) select s; </code></pre> <p>Runtime error: <code>NotSupportedException: Unable to create a constant value of type 'Models.Tag'. Only primitive types ('such as Int32, String, and Guid') are supported in this context.</code> Any ideas?</p> <p>-- update Jan. 4: The answers point to the right solution, but in my code I still have the NotSupportedException. Is it possible the nullable integer causes this since it is not a primitive type?</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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