using STI and ActiveRecordBase<> with full FindAll
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            by oillio
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        Published on 2010-05-05T17:47:59Z
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            2010/05/08
            2:28 UTC
        
        
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Is it possible to use generic support with single table inheritance, and still be able to FindAll of the base class?
As a bonus question, will I be able to use ActiveRecordLinqBase<> as well? I do love those queries.
More detail: Say I have the following classes defined:
public interface ICompany
{
    int ID { get; set; }
    string Name { get; set; }
}
[ActiveRecord("companies", 
  DiscriminatorColumn="type", 
  DiscriminatorType="String", 
  DiscriminatorValue="NA")]
public abstract class Company<T> : ActiveRecordBase<T>, ICompany
{
    [PrimaryKey]
    private int Id { get; set; }
    [Property]
    public String Name { get; set; }
}
[ActiveRecord(DiscriminatorValue="firm")]
public class Firm : Company<Firm>
{
    [Property]
    public string Description { get; set; }
}
[ActiveRecord(DiscriminatorValue="client")]
public class Client : Company<Client>
{
    [Property]
    public int ChargeRate { get; set; } 
}
This works fine for most cases. I can do things like:
var x = Client.FindAll();
But sometimes I want all of the companies. If I was not using generics I could do:
var x = (Company[]) FindAll(Company);
Client a = (Client)x[0];
Firm b = (Firm)x[1];
Is there a way to write a FindAll that returns an array of ICompany's that can then be typecast into their respective types?
Something like:
var x = (ICompany[]) FindAll(Company<ICompany>);
Client a = (Client)x[0];
Or maybe I am going about implementing the generic support all wrong?
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