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PORemoving a navigation property doesn't update the database
 

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    <p>I have 2 POCO classes (below) and wish to remove the link between two of their records. According to <a href="http://msdn.microsoft.com/en-us/data/jj713564.aspx" rel="nofollow">this</a> EF 5.0 should be able to handle the removal without loading the User class like so:</p> <pre><code>context.Computers.Find("test").User = null; context.SaveChanges(); </code></pre> <p>This doesn't work, but using the .net 4 approved method it works:</p> <pre><code>en = context.Computers.Find("test"); context.Entry(en).Reference(e =&gt; e.User).Load(); en.User = null; context.SaveChanges(); </code></pre> <p>My EF reference is EntityFramework.dll version 5.0.0.0. Am I missing something obvious here?</p> <p>Here are the classes:</p> <pre><code>public class Computer { public string Id { get; set; } public Nullable&lt;int&gt; UserId { get; set; } public virtual User User { get; set; } } public class User { public int Id { get; set; } public virtual ICollection&lt;Computer&gt; Computers { get; set; } } </code></pre> <p>Edit: Here is the specific lines in the above linked article that don't seem to agree with the functionality I'm seeing: </p> <p>To delete the relationship, set the navigation property to null. If you are working with the Entity Framework that is based on .NET 4.0, then the related end needs to be loaded before you set it to null. For example:</p> <pre><code>context.Entry(course).Reference(c =&gt; c.Department).Load(); course.Department = null; </code></pre> <p>Starting with the Entity Framework 5.0, that is based on .NET 4.5, you can set the relationship to null without loading the related end.</p>
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    1. CODon't you mean `context.Computers` instead of `context.Users` and `...Find("test").UserId = null;` instead of `...Find("test").User = null;`?
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      1. USSlauma
    2. COYes on the Users (i've made the update). For ...Find("test").User = null; is correct. I'm setting the navigation property to null in order to unlink the User from the computer.
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    3. CODid you disable lazy loading or proxy creation? Your first line relies on lazy loading to be enabled, otherwise it won't work. But with lazy loading it will load the `User` - in contrast to your expectation. If you don't want that, set the `UserId` to `null`.
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