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From: <mao@postgres.berkeley.edu>
Subject: Re: Postgres and Polymorphism
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In-Reply-To: Your message of Wed, 03 Feb 93 19:12:41 EST.
             <9302031912.aa07916@concour.cs.concordia.ca> 
Date: Wed, 03 Feb 93 17:10:53 PST

In message <9302031912.aa07916@concour.cs.concordia.ca> you write:

> Is there a way to know which subclass an object comes from without doing
> the extra selects? Or is there a way to achieve polymorphism?

no, but enough people are interested in this that we may add it to
a future release of the system.

> I also have a related questions : when you do a retrieve on B*, the
> result is a set of objects of type B, i.e. all the objects of type C1
> and C2 are casted into type B by the operation. Is there a way to
> preven that? The retrieve would them give me all the objects in all
> the subclasses each with all their attributs...
> If this could be done (and I could know which class an object belongs
> to), I could write a method in the base class to do all my testing.

this is a bug, and will be fixed in a future release of the system.