Re: Fwd: Re: SQL3 UNDER

"Robert B. Easter" wrote:
> Well, I hope some one sees my point about INHERITS and UNDER
> maybe being complementary.  UNDER is a single inheritance container/tree all
> contained inside maximal supertable.  INHERITS provides multiple inheritance
> and can provide links between tables in different containers/trees, subject to
> some restrictions.  I think it deserves some looking at rather than just doing
> away with INHERIT for just UNDER.  (again I can be wrong).  I guess its hard to
> explain.  I still need to provide good examples.  I can best describe the
> difference as UNDER creates circles within circles representing tables and
> subtables.  INHERITS provides for circles/tables to overlap (to be cloned in a
> sense) and allows it multiple overlapping/merging.  The INHERITS does it as it
> is now that way, by merging same name attributes from two or more parents into a
> single child.  INHERIT is like cells reproducing using one or n parents.
> UNDER is like a single cell making baby cells inside of itself.   :-)  hehe

Would you still be having these thoughts if you were looking at the
older SQL3 draft that included multiple inheritance UNDER? The newer
UNDER appears to be a subset, which I presume they adopted to get the
proposal out the door quicker. Personally I'd like to implement the
SQL3-1994 extensions as well, because they actually seemed well thought
out (I'm thinking particularly of the rename stuff).