Re: MULTISET and additional functions for ARRAY

Itagaki Takahiro <itagaki.takahiro@gmail.com>

From: Itagaki Takahiro <itagaki.takahiro@gmail.com>
To: Darren Duncan <darren@darrenduncan.net>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2010-11-12T01:36:34Z
Lists: pgsql-hackers
On Fri, Nov 12, 2010 at 06:06, Darren Duncan <darren@darrenduncan.net> wrote:
> This is one place that SQL made things more complicated than they needed to
> be.  Multisets have generally the same structure *and* operators (union,
> etc) as tables, but they use different syntax for each.  A better design
> would be to make tables and multisets interchangeable.  Its an unnecessary
> distinction.

We can use unnest() to convert MULTISET into TABLE, and collect() agg
function from TABLE to MULTISET. I don't think they need to have the
same on-disk structure; they can share operators and constructor syntax
even now.

-- 
Itagaki Takahiro