Hello Mark,

>Seems to me that the relational and object oriented models
>are rather different, and running a system that uses
>both is bound to incur some "translation" overhead.
>
>This, I suspect, could lead us into a "first principles"
>debate which is rarely as clearcut (in the real world) as
>it is in principle.
>
>I think that any use of the object model requires more
>sophisticated use than the relational or flat. This
>only "may" lead to "performance troubles".

Well, certainly it is always a difference between real world and theory. Anyway i don't pretend to debate this, but it would be interesting that you talk with Arnon this friday's conferece (at 3 PM) about OOAD vs. Relational AD, of course if you can reach him before he goes to the movies :)

Ciao,

J. Luis