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POPossible Bug in Migration for EF 6 Alpha 3 on recursive relationship?
 

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  1. POPossible Bug in Migration for EF 6 Alpha 3 on recursive relationship?
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    <p>I had to define a recursive relationship on a composite key. After much trials, I ended up with this:</p> <pre><code>protected override void OnModelCreating(DbModelBuilder modelBuilder) { base.OnModelCreating(modelBuilder); modelBuilder.Entity&lt;Category&gt;() .Property(t =&gt; t.WhichAmazon).HasDatabaseGeneratedOption(DatabaseGeneratedOption.None); modelBuilder.Entity&lt;Category&gt;() .Property(t =&gt; t.IdCategory).HasDatabaseGeneratedOption(DatabaseGeneratedOption.None); modelBuilder.Entity&lt;Category&gt;() .HasKey(c =&gt; new {c.WhichAmazon, c.IdCategory}) .HasOptional(p =&gt; p.Children) .WithMany() .HasForeignKey(c =&gt; new { c.WhichChildrenAmazon, c.ChildrenId }); } </code></pre> <p>for this table</p> <pre><code>public class Category { // Keys and relationships defined in BooksDataLayer [MaxLength(2)] public string WhichAmazon { get; set; } public int IdCategory { get; set; } public string Name { get; set; } [Timestamp] public Byte[] TimeStamp { get; set; } public DateTime LastCheck { get; set; } public virtual List&lt;Book&gt; Books { get; set; } public string WhichChildrenAmazon { get; set; } public int? ChildrenId { get; set; } public virtual List&lt;Category&gt; Children { get; set; } } </code></pre> <p>While trying to Add-Migration I was constantly having the same error: "Sequence contains no elements". As I was "almost" sure this definition was right, I went ahead a re-created a new Db, WITHOUT migration. Was perfectly OK, no problems with the Db at all. So there is "something" in there which EF 6 does not like. I had a confirmation, as EF power tools bombs if I try to get a schema "Exception has been thrown by the target of an invocation". </p> <p>I'll see what happens now with migration if I restart from there, but I am afraid to not be able to use anymore with this Db. I do like the tool, a lot, so I hope this can be fixed.</p>
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