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POEntity Framework "The relationship could not be changed" with simple one-to-many
 

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    <p>I'm trying to remove a relationship with the following code: </p> <pre><code> var serverVideo = InternalGetVideo(db, videoId); // get owning user var owner = InternalGetUser(db, serverVideo.UserId); // Add/remove video to user's upvotedVideos if (owner.UpvotedVideos.Contains(serverVideo)) { serverVideo.UpVotes--; SaveChanges(db); // Works owner.UpVotes--; SaveChanges(db); // Works owner.UpvotedVideos.Remove(serverVideo); SaveChanges(db); // Breaks } SaveChanges(db); </code></pre> <p>But I always get this error: </p> <blockquote> <p>The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.</p> </blockquote> <p>I'm not trying to delete the video, I'm just trying to remove it from the user's UpvotedVideos property (it's there): </p> <pre><code>[Table("UserProfile")] public class UserProfile { [Key] [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)] public int UserId { get; set; } public string Username { get; set; } public int UpVotes { get; set; } public virtual List&lt;Video&gt; UpvotedVideos { get; set; } public string Email { get; set; } } </code></pre> <p>Videos does not contain a reference to UserProfiles - it's a one-to-many relationship. Any idea what I'm doing wrong?</p> <p>Videos class: </p> <pre><code>[DataContract] public class Video { [Key] [DataMember(IsRequired = false)] public int VideoId { get; set; } [DataMember(IsRequired = false)] public int UserId { get; set; } // user that created the video, unrelated [Required] [DataMember] public virtual IList&lt;Tag&gt; Tags { get; set; } } </code></pre>
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    1. COI think it might be helpful if you could post your `Video` class, at least the parts dealing with the relationship to `UserProfile` (the foreign key and the relationship property).
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    2. CO@Steve - thanks, done
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    3. COI'm assuming `db` is your context and is not disposed of throughout?
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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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