Re: Fwd: Re: SQL3 UNDER

From: Chris Bitmead <chrisb(at)nimrod(dot)itg(dot)telstra(dot)com(dot)au>
To: "Robert B(dot) Easter" <reaster(at)comptechnews(dot)com>
Cc: Hannu Krosing <hannu(at)tm(dot)ee>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Fwd: Re: SQL3 UNDER
Date: 2000-05-24 23:34:58
Message-ID: 392C6722.2AD9BF05@nimrod.itg.telecom.com.au
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

"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).

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Chris Bitmead 2000-05-24 23:45:59 Re: AW: Postgresql OO Patch
Previous Message Tom Lane 2000-05-24 23:00:53 Re: understanding Datum -> char * -> Datum conversions