From: Marcus Andersson <m-lists@...>
Date: 2006-06-29T05:51:33+09:00
Subject: Re: How to model Hibernate multi-table inheritance with ActiveRecord?

Hello Jacob,

I sort of like this solution but I have one problem. Querying. Say I 
want to query the complete set of Assets and I don't care what 
underlying [other]Asset they have. Then I have to do:

assets = Asset.find(:all, :condition => "somecondition")

But, I always need to get the delegate from the assets in order to work 
with them. Thus the above expression changes to:

assets = Asset.find(:all, :condition => 
"somecondition").map(&:delegate_asset)

Now I have the correct asset instances to work with. The problem is that 
I have to do that extra map() all over the place. 1) It violates DRY and 
2) someone will forget it

Is there a solution to this (apart from decreing project wide that you 
may never query Asset outside of Asset itself and thereby encapsulate 
all queries)?

/Marcus