To: "Lodewijk Voege" <lvoege@gmail.com>
cc: pgsql-sql@postgresql.org
Subject: Re: information_schema.referential_constraints permissions 
In-reply-to: <2d734e2f0804281447l5de57868na1a5415b0a95ee28@mail.gmail.com> 
References: <2d734e2f0804281447l5de57868na1a5415b0a95ee28@mail.gmail.com>
Comments: In-reply-to "Lodewijk Voege" <lvoege@gmail.com>
	message dated "Mon, 28 Apr 2008 17:47:59 -0400"
Date: Mon, 28 Apr 2008 19:14:58 -0400
Message-ID: <19206.1209424498@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

"Lodewijk Voege" <lvoege@gmail.com> writes:
> I have some code that gets foreign key information from
> information_schema.referential_constraints. I was puzzled about why it wasn't
> returning anything for a while, until I read the information_schema.sql file
> and the documentation carefully: it has a pg_has_role(c.relowner, 'USAGE') in
> it and the documentation states "The view referential_constraints contains all
> referential integrity (foreign key) constraints in the current database that
> belong to a table owned by a currently enabled role".

> Fair enough. But then I read the public draft of SQL 2003 and 200n on this
> view, and it speaks only of "tables in this catalog that are accessible to a
> given user or role", rather than ownership. the user I was working with most
> definately had access.

The SQL committee changed that recently --- SQL92 and SQL99 define the
view as

         Identify the referential constraints defined in this catalog that
         are owned by a given user.

I don't think we've gotten around to trying to sync information_schema
with SQL2003.  (The whole concept that information_schema might be a
moving target is pretty disturbing :-()

			regards, tom lane