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copied!<p>In terms of entities (or objects) you have a <code>Class</code> object which has a collection of <code>Students</code> and a <code>Student</code> object that has a collection of <code>Classes</code>. Since your <code>StudentClass</code> table only contains the Ids and no extra information, EF does not generate an entity for the joining table. That is the correct behaviour and that's what you expect.</p> <p>Now, when doing inserts or updates, try to think in terms of objects. E.g. if you want to insert a class with two students, create the <code>Class</code> object, the <code>Student</code> objects, add the students to the class <code>Students</code> collection add the <code>Class</code> object to the context and call <code>SaveChanges</code>:</p> <pre><code>using (var context = new YourContext()) { var mathClass = new Class { Name = "Math" }; mathClass.Students.Add(new Student { Name = "Alice" }); mathClass.Students.Add(new Student { Name = "Bob" }); context.AddToClasses(mathClass); context.SaveChanges(); } </code></pre> <p>This will create an entry in the <code>Class</code> table, two entries in the <code>Student</code> table and two entries in the <code>StudentClass</code> table linking them together.</p> <p>You basically do the same for updates. Just fetch the data, modify the graph by adding and removing objects from collections, call <code>SaveChanges</code>. Check <a href="https://stackoverflow.com/questions/3612477/entity-framework-4-many-to-many-update/3622599#3622599">this similar question</a> for details.</p> <p><strong>Edit</strong>:</p> <p>According to your comment, you need to insert a new <code>Class</code> and add two existing <code>Students</code> to it:</p> <pre><code>using (var context = new YourContext()) { var mathClass= new Class { Name = "Math" }; Student student1 = context.Students.FirstOrDefault(s => s.Name == "Alice"); Student student2 = context.Students.FirstOrDefault(s => s.Name == "Bob"); mathClass.Students.Add(student1); mathClass.Students.Add(student2); context.AddToClasses(mathClass); context.SaveChanges(); } </code></pre> <p>Since both students are already in the database, they won't be inserted, but since they are now in the <code>Students</code> collection of the <code>Class</code>, two entries will be inserted into the <code>StudentClass</code> table.</p>

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