From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Shigeru Hanada <shigeru.hanada@gmail.com>,
 KaiGai Kohei <kaigai@ak.jp.nec.com>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: inherit support for foreign tables
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
 message dated "Tue, 21 Jan 2014 14:09:39 -0500"
Date: Tue, 21 Jan 2014 15:00:59 -0500
Message-ID: <1061.1390334459@sss.pgh.pa.us>
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Robert Haas <robertmhaas@gmail.com> writes:
> One thing that's bugging me a bit about this whole line of attack is
> that, in the first instance, the whole goal here is to support
> inheritance hierarchies that mix ordinary tables with foreign tables.
> If you have a table with children some of which are inherited and
> others of which are not inherited, you're very likely going to want
> your constraints enforced for real on the children that are tables and
> assumed true on the children that are foreign tables, and none of what
> we're talking about here gets us to that, because we normally want the
> constraints to be identical throughout the inheritance hierarchy.

There's a nearby thread that's addressing this same question, in which
I make the case (again) that the right thing for postgres_fdw constraints
is that they're just assumed true.  So I'm not sure why this conversation
is proposing to implement a lot of mechanism to do something different
from that.

			regards, tom lane


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