Re: MULTISET and additional functions for ARRAY - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: MULTISET and additional functions for ARRAY
Date
Msg-id 1289505981-sup-5481@alvh.no-ip.org
Whole thread Raw
In response to Re: MULTISET and additional functions for ARRAY  ("David E. Wheeler" <david@kineticode.com>)
Responses Re: MULTISET and additional functions for ARRAY
List pgsql-hackers
Excerpts from David E. Wheeler's message of jue nov 11 15:45:55 -0300 2010:
> On Nov 11, 2010, at 10:19 AM, Darren Duncan wrote:
> 
> > I think that it would be best to implement MULTISET in the same way that a TABLE is implemented. Logically and
structurallythey are the same thing, but that a MULTISET typically is used as a field value of a table row.  Aka, a
tableand a multiset are just different names for a relation, loosely speaking.
 
> 
> That sounds like a composite type to me.

No, it's "perpendicular" in the sense that while a composite type allows
you to have different columns, this multiset thing lets you have "rows"
(I initially thought about them as sets of scalars, but AFAIU they could
in turn be rows)

-- 
Álvaro Herrera <alvherre@commandprompt.com>
The PostgreSQL Company - Command Prompt, Inc.
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