To: Peter Eisentraut <peter_e@gmx.net>, pgsql-admin@postgresql.org,
	Caleb Cushing <xenoterracide@gmail.com>, Bruce Momjian <bruce@momjian.us>
Subject: Re: pg_dump formatting 
In-reply-to: <11595.1237733040@sss.pgh.pa.us> 
References: <81bfc67a0903192135v1caa41abtd4618f3df0642834@mail.gmail.com>
	<15202.1237611487@sss.pgh.pa.us>
	<81bfc67a0903212126g7377d7e4i55736a663bccf0dc@mail.gmail.com>
	<200903221010.44907.peter_e@gmx.net>
	<11595.1237733040@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Sun, 22 Mar 2009 10:44:00 -0400"
Date: Sun, 22 Mar 2009 13:09:36 -0400
Message-ID: <14030.1237741776@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>

I wrote:
> Peter Eisentraut <peter_e@gmx.net> writes:
>> Maybe wdiff will do what you want.

> I don't think we'd consider making the kind of changes to the COPY
> specification that would be needed to allow this sort of thing in COPY
> mode.  However, it'd be pretty trivial to put \n instead of space
> between fields in the INSERT dump formats.  I wonder whether that would
> answer the need ...

On further reflection I think Peter's suggestion is better.  It's not
hard to think of cases where a data-value-per-line format is *less*
useful not more so for diff-ing, because you lose all sense that a
table row is one logical unit.  What the OP seems to be concerned about
is insertion/modification/deletion of words within fairly long data
fields.  wdiff is ideal for that problem, while simply breaking at field
boundaries wouldn't help all that much.

			regards, tom lane