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POCode First and Parent-Child references
 

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    <p>I'm using Code First CTP 5. I have a fairly simple setup between a parent table and child tables</p> <pre><code>Create table testA ( id int not null identity(1,1), stuff varchar(200), primary key (id) ); go create table testB ( id int not null foreign key references testA(id), morestuff varchar(200), primary key (id) ); go </code></pre> <p>To refer to these table using Code First, we have the following construct:</p> <pre><code>namespace Test.Models { public class TestEntities : DbContext { public DbSet&lt;testa&gt; testa { get; set; } public DbSet&lt;testb&gt; testb { get; set; } protected override void OnModelCreating(System.Data.Entity.ModelConfiguration.ModelBuilder modelBuilder) { base.OnModelCreating(modelBuilder); modelBuilder.Entity&lt;testa&gt;().ToTable("testa"); modelBuilder.Entity&lt;testa&gt;() .Property(p =&gt; p.id) .HasDatabaseGenerationOption(DatabaseGenerationOption.Identity); modelBuilder.Entity&lt;testb&gt;().ToTable("testb"); } } public class testa { public int id { get; set; } public String stuff { get; set; } public virtual testb testb { get; set; } } public class testb { public int id { get; set; } public string morestuff { get; set; } public virtual testa testa { get; set; } } } </code></pre> <p>When I try to add a record to testa, I get the error "Cannot insert explicit value for identity column in table 'testA' when IDENTITY_INSERT is set to OFF." </p> <p>Ok. Strike 1 to Code First for not recognizing that Id is an identity column. We can fix this, so we tell CodeFirst that testa.id is an identity:</p> <pre><code> modelBuilder.Entity&lt;testa&gt;() .Property(p =&gt; p.id) .HasDatabaseGenerationOption(DatabaseGenerationOption.Identity); </code></pre> <p>That done we run it again and get another error: "A dependent property in a ReferentialConstraint is mapped to a store-generated column. Column: 'id'". So - what's wrong with this picture?</p> <p>What am I doing wrong and how do I fix it???</p>
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