Duplicate entries - linq-to-sql

Question

I have created a universalrepository that takes the type passed to it and when I create data entry method, the entity is created fine, but when I create a linked entity to it, i get the base entity created again. Any ideas why?
Details..
I have divided a specification into multiple tables to manage stuff...
Now I have got a person entity, an applicant entity...(in reality applicant and person are the same), a contractor entity. A contractor can only be created by an applicant and therefore an applicant will always be created and therefore a person will always be created.
When I go on creating a person, it creates a person fine, but when I create an applicant it creates a person again. Likewise when I create a contractor it creates a person and multiple applicants for some reason.
Here is my LINQ to SQL. If you notice in anyway I can improve this code, I will appreciate that too.
here is the repository
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Linq;
namespace ParkingPermit.Models
{
public class UniversalManagerRepository<T> :IRepositoryT<T>
where T:class
{
private Table<T> _table;
private readonly DB _db ;//= new DB();
public UniversalManagerRepository()
{
_db = new DB();
_table = _db.GetTable<T>();
}
#region IRepositoryT<T> Members
public T Create(T create)
{
// _table = new DB().GetTable<T>();
//_db.GetTable(typeof(T)).InsertOnSubmit(create);
_table.InsertOnSubmit(create);
Save();
return create;
}
public void Delete(T delete)
{
throw new NotImplementedException();
}
public T Edit(T edit)
{
throw new NotImplementedException();
}
public T GetItem(int id)
{
throw new NotImplementedException();
}
public T Update(T update)
{
throw new NotImplementedException();
}
public IEnumerable<T> List()
{
//IQueryable i = _db.GetTable(typeof(T)).AsQueryable() ;
return _db.GetTable(typeof(T)) as IEnumerable<T>;
//throw new NotImplementedException();
}
public void Save()
{
//_db.SubmitChanges();
_table.Context.SubmitChanges();
//throw new NotImplementedException();
}
#endregion
}
}
I can post an image of the linq to sql designer if that helps, but I cant see the feature here...
Many thanksalt text http://img509.imageshack.us/img509/2072/linq.jpg
the thing is that when applicant is added and an applicant.Person is assigned from the session(in model binder), it creates a new person, which is actually the original person created in the beginning. How can I avoid that.
protected override void OnModelUpdated(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
var personType = (Person)controllerContext.HttpContext.Session[PersonSessionKey];
controllerContext.HttpContext.Session[CurrentApplicantSessionKey] = null;
var av = new ApplicantValidator(new ModelStateWrapper(bindingContext.ModelState));
var newApplicant = bindingContext.Model as Applicant;
if (personType == null)
{
bindingContext.ModelState.AddModelError(bindingContext.ModelName,
"Cannot Update this Instance directly, please restart the application");
// controllerContext.HttpContext.Session[PersonSessionKey] = personType;
}
else if (newApplicant != null)
{
if (newApplicant.Person != null)
{
if (newApplicant.Person.Equals(personType as Person))
{
bindingContext.ModelState.AddModelError(bindingContext.ModelName,
"A person with these details already exists, please restart the application...");
//return
controllerContext.HttpContext.Session[PersonSessionKey] = null;
personType = null;
}
}
else if (av.Validate(newApplicant))
{
if (newApplicant.Person == null)
{
newApplicant.Person = personType as Person;
newApplicant.PersonId = personType.PersonId;
}
}
}
}

Answer 1

I have resolved this part and apparently its now giving issued with update, can anbody find anything unusual.
Answer to my first problem, was that in Model Binders the entity is being manipulated from sessions and the created back to the service layer.
Apparently it seems that because its all happening outside linq orm framework, this entity needs to be recreated as "From clause ...from ..in db." and then linq correctly recognizes it and does the correct job of insertion.
Can anyone help me with the update/edit..please