Add Support for One-Way Associations

You indeed can acheive this using a link table, as I mentioned in my request. The table has two fields that holds the ids of the containing and the contained items and is unique across those two fields.
Regards
Sean

Hello Sean,
We have found an intermediate solution to your task. Please explore the attached sample project. It uses a link table to represent a one-to-many association between two objects which aren't linked to each other directly at the database level. Hopefully, it will come in handy. We'll appreciate your feedback on our sample project.
Thanks,
Nick

Hi Nick
I'm not sure that it's for me to suggest implementation specifics as you
guys are the XPO experts. However, as you're asking, I would suggest that
you approach it as I suggested in the original suggestion and use a link
table to store the one-way association. This is the same as the data
structure you use to store a many-many association. The only difference is
that you only select from it from one side.
I hope that makes sense - let me know if it doesn't.
Cheers
Sean

Hello Sean,
There is one more thing we need to clarify. What is your situation, which prevents you from defining the associated member in your persistent class? Said differently, please describe your Use Case.
Thanks,
Nick

Hi Nick
Other than the discussion in the DX forums, I've put some stuff up on my blog here (http://kearon.blogspot.com/2008/11/why-support-one-way-multiple.html).
HTH
Sean

Hello Sean,
Thank you for the explanation. However, your example doesn't provide the implementation of the Customer.RecentProducts property. There is just the "get" keyword. Could you please explain how the Customer.RecentProducts property is implemented?

C#
public class Customer : XPObject  
{  
    public XPCollection RecentProducts {  
        get {  
            ???  
        }  
    }  
}  

Thanks,
Nick

Hi Nick
I am actually calling GetCollection<T>(string) in the getter, as you would normally do. However, I am also using C# automatic properties with XPO, but that is incidental. I use code enchancement to do that (with PostSharp - http://www.postsharp.org/). If you are interested, you can read my posts here and here; there are links to downloadable code examples also, as there was with the post about implemting one-way multiple associations.
Cheers
Sean

Hi Sean,
The GetCollection<T> method expects the name of an associated property as a parameter. In your situation, you should explicitly create an XPCollection object:

C#
public class Customer : XPObject  
{  
    private XPCollection<Product> recentProducts;  
    public XPCollection<Product> RecentProducts {  
        get {  
            if(recentProducts == null) {  
                 CriteriaOperator filter = ... // define some filter to select recent products for a given customer  
                 recentProducts = new XPCollection<Product>(Session, filter);  
            }  
            return recentProducts;  
        }  
    }  
}  

You can find tons of examples about creating CriteriaOperator filters in the Support Center. Please feel free to ask additional questions.
Thanks,
Nick

Hi Nick
Your solution is indeed workable in the described scenario, but my request for one-way associations has nothing to do with a supporting a specific scenario. It is to reduce the code necessary to support a 0…* association in situations where you do not need or want a reverse link.
I'm also confused as you have previously set the request to be "Accepted - Release TBD", but you have now set it to "Rejected". Couild you please clarify why?
Thanks
Sean
Thanks
Sean