To: Bruce Momjian <bruce@momjian.us>
cc: "Dickson S. Guedes" <guediz@gmail.com>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: TODO item: Have psql show current values for a sequence 
In-reply-to: <200807150317.m6F3HSd06034@momjian.us> 
References: <200807150317.m6F3HSd06034@momjian.us>
Comments: In-reply-to Bruce Momjian <bruce@momjian.us>
	message dated "Mon, 14 Jul 2008 23:17:28 -0400"
Date: Mon, 21 Jul 2008 01:38:16 -0400
Message-ID: <29373.1216618696@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

Bruce Momjian <bruce@momjian.us> writes:
> Wow.  I adjusted the patch slightly and applied it;  the updated version
> is attached.  We have been waiting for this to be done for quite some
> time.  Thanks.

Hmm ... I don't think that this patch actually addresses the TODO item.
The TODO item seems to have originated here
http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1220;r2=1.1221;f=h
in response to this question on pgsql-novice:

> How can I list all the sequences in the database, with their
> attributes (such as last_value)?  (I'm having a hard time guessing
> 'seq-name'; the 'A_id_seq' formula did not work.)
http://archives.postgresql.org/pgsql-novice/2004-02/msg00148.php

This applied-with-little-discussion patch only shows the sequence
values if you do a \d on a specific sequence, or \d on a wildcard
that happens to include some sequences (and probably a lot of other
stuff too, causing the resulting display to be far too long to be
useful).

My interpretation of the TODO item has always been that we should
improve \ds to include all the useful information in a format that
requires only one line per sequence.  The reason it has remained
undone for four years is that that's hard given the existing catalog
representation of sequences and the constraints of describe.c's
implementation.  (I recall at least one failed patch that tried to
do this, though I can't find it in the archives right now.)

I find the present patch to be pretty useless: it's not a material
advance over doing "select * from sequence-name".  I think it should
be reverted and the TODO item reinstated --- perhaps with more detail
about what the item really is requesting.

			regards, tom lane