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copied!<p>In <a href="/questions/tagged/entity-framework-5" class="post-tag" title="show questions tagged 'entity-framework-5'" rel="tag">entity-framework-5</a>, this is insanely easy with the <a href="http://msdn.microsoft.com/en-us/library/system.data.entity.dbextensions.asnotracking(v=vs.103).aspx">DbExtensions.AsNotracking()</a>. </p> <blockquote> <p>Returns a new query where the entities returned will not be cached in the DbContext or ObjectContext.</p> </blockquote> <p>This appears to be the case for all objects in the object graph.</p> <p>You just have to really understand your graph and what you do and don't want inserted/duplicated into the DB.</p> <p>Lets assume we have objects like:</p> <pre><code>public class Person { public int ID { get; set; } public string Name { get; set; } public virtual ICollection<Address> Addresses { get; set; } } public class Address { public int ID { get; set; } public AddressLine { get; set; } public int StateID { get; set; } public ICollection<State> { get; set; } } </code></pre> <p>So in order to Duplicate a person, I need to duplicate the addresses, but I don't want to duplicate the States.</p> <pre><code>var person = this._context.Persons .Include(i => i.Addresses) .AsNoTracking() .First(); // if this is a Guid, just do Guid.NewGuid(); // setting IDs to zero(0) assume the database is using an Identity Column person.ID = 0; foreach (var address in person.Addresses) { address.ID = 0; } this._context.Persons.Add(person); this._context.SaveChanges(); </code></pre> <p>If you then wanted to then reuse those same objects again to insert a third duplicate, you'd either run the query again (with AsNoTracking()) or detach the objects (example):</p> <pre><code>dbContext.Entry(person).State = EntityState.Detached; person.ID = 0; foreach (var address in person.Addresses) { dbContext.Entry(address).State = EntityState.Detached; address.ID = 0; } this._context.Persons.Add(person); this._context.SaveChanges(); </code></pre>

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