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POError Related to FK in One-to-Many Relationship
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  1. POError Related to FK in One-to-Many Relationship
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    copied!<p>I am using EF 5 Beta 2 Code-First. I have created an edmx file which has 2 entities among others named <em>Brand</em> and <em>Vehicle</em>.</p> <p>One <em>Brand</em> can have zero or more (many) <em>Vehicles</em> and every <em>Vehicle</em> should have a <em>Brand</em> (required). <em>Vehicle</em> has a foreign key named <em>BrandID</em> which is <em>non-nullable</em>.</p> <pre><code>(relationship) Brand +-------------------&gt; Vehicle (1) (*) </code></pre> <p>Also I did use <em>EF 5 DbContext Generator</em> to create POCO classes.</p> <h2>The Problem</h2> <p>When I try to either Read or Write records, I get the following error:</p> <p><strong>error 3023: Problem in mapping fragments starting at line 155:Column Vehicle.BrandID in table Vehicle must be mapped: It has no default value and is not nullable.</strong></p> <p>Notice: I am using <strong>TPC</strong> inheritance mapping where Vehicle is an <em>abstract base class</em> from which 2 classes (<em>Car</em> &amp; <em>Motorbike</em>) are being derived.</p> <p>Here is class definition plus related fluent API code:</p> <pre><code>//------------ Class definiions --------------- public abstract partial class Vehicle { public int VehicleID { get; set; } public short BrandID { get; set; } public virtual Brand Brand { get; set; } public partial class Car : Vehicle { public string BodyType { get; set; } } public partial class Motorbike : Vehicle { } public partial class Brand { public Brand() { this.Vehicles = new HashSet&lt;Vehicle&gt;(); } public short BrandID { get; set; } public string Name { get; set; } public virtual ICollection&lt;Vehicle&gt; Vehicles { get; set; } } //--------------- Fluent API code --------------- modelBuilder.Entity&lt;Vehicle&gt;() .Property(p =&gt; p.VehicleID) .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); modelBuilder.Entity&lt;Car&gt;() .Map(m =&gt; { m.ToTable("Car"); m.MapInheritedProperties(); }); modelBuilder.Entity&lt;Motorbike&gt;() .Map(m =&gt; { m.ToTable("Motorbike"); m.MapInheritedProperties(); }); modelBuilder.Entity&lt;Brand&gt;() .HasMany(b=&gt;b.Vehicles) .WithRequired(v=&gt;v.Brand) .HasForeignKey(p =&gt; p.BrandID); modelBuilder.Entity&lt;Brand&gt;() .Property(p =&gt; p.BrandID) .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity); </code></pre> <p>This is so strange since everything seems OK and has been checked several times.</p> <p>Any thoughts would be greatly appreciated.</p>
 

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