Cannot Insert duplicate key on related table - entity-framework

Question

My model has Owners and Complexes. An owner can have many complexes, and a complex could theoretically have multiple owners (joint ownership). I want to be able to create new complexes and owners independently, so neither should require the other. However, when I try to add a new complex, I get this error:
Violation of PRIMARY KEY constraint 'PK_dbo.Owners'. Cannot insert duplicate key in object 'dbo.Owners'. The duplicate key value is (fcd72b09-b1ef-4894-83de-cb4897c0c401).
The statement has been terminated.
For the record, there is currently one existing owner (with the ID mentioned in the error). The owner is already associated with another complex. I should be able to add a new complex with this owner, but obviously it's not allowing me to.
What do I need to change with my model to accomodate this? Relevant code follows:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
//modelBuilder.Entity<Complex>().ToTable("Complex");
//modelBuilder.Entity<Unit>().ToTable("Unit");
//modelBuilder.Entity<Address>().ToTable("Addresses");
//modelBuilder.Entity<Tenant>().ToTable("Tenant");
modelBuilder.Entity<ContactInfo>().ToTable("Contacts");
modelBuilder.Conventions.Remove<ManyToManyCascadeDeleteConvention>();
modelBuilder.Entity<Complex>()
.HasOptional(x => x.Owner)
.WithMany(x => x.Complexes);
modelBuilder.Entity<Unit>()
.HasOptional(x => x.Complex)
.WithMany(x => x.Units);
modelBuilder.Entity<Owner>()
.HasMany(x => x.Complexes);
base.OnModelCreating(modelBuilder);
}
}
Owner and Complex models:
public class Owner
{
[Key]
public Guid Id { get; set; }
public string Name { get; set; }
public Guid? ContactInfoId { get; set; }
[ForeignKey("ContactInfoId")]
public ContactInfo ContactInfo { get; set; }
public ICollection<StaffMember> Employees { get; set; }
public ICollection<Complex> Complexes { get; set; }
public Owner()
{
this.Id = System.Guid.NewGuid();
this.Employees = new HashSet<StaffMember>();
this.Complexes = new HashSet<Complex>();
}
public void AddEmployee(StaffMember employee)
{
Employees.Add(employee);
}
public void AddComplex(Complex complex)
{
Complexes.Add(complex);
}
}
public class Complex
{
[Key]
public Guid Id { get; set; }
public string Name { get; set; }
public Guid? OwnerId { get; set; }
[ForeignKey("OwnerId")]
public Owner Owner { get; set; }
public Guid? AddressId { get; set; }
[ForeignKey("AddressId")]
public virtual Address Address { get; set; }
public virtual ICollection<Unit> Units { get; set; }
public virtual ICollection<StaffMember> StaffMembers { get; set; }
public Complex()
{
this.Id = System.Guid.NewGuid();
this.Units = new HashSet<Unit>();
this.StaffMembers = new HashSet<StaffMember>();
}
public void AddUnit(Unit unit)
{
Units.Add(unit);
}
public void AddStaff(StaffMember staffMember)
{
StaffMembers.Add(staffMember);
}
}

Answer 1

Your entities aren't setup correctly. In your Complex object, you are stating that it has only 1 owner so you're setting it up as a one to many instead of a many to many. If you set it as a collection instead of an object, EF will handle the many to many table for you