Re: pg_rawdump

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Stephen R. van den Berg" <srb@cuci.nl>
Cc: Robert Haas <robertmhaas@gmail.com>, Aidan Van Dyk <aidan@highrise.ca>, Roberto Mello <roberto.mello@gmail.com>, Greg Stark <gsstark@mit.edu>, pgsql-hackers@postgresql.org
Date: 2010-10-21T14:11:51Z
Lists: pgsql-hackers
"Stephen R. van den Berg" <srb@cuci.nl> writes:
> Robert Haas wrote:
>> and break on-disk compatibility just to make it easier to

> If it's inserted in the "special" area, it will not break any
> compatibility.

I'll tell you what I really don't like about this proposal: we discuss
some scheme or other for taking over the "special space" in heap pages
at least once a year.  None of them have been particularly compelling
so far, but one may come along that is; especially given that we're now
trying to maintain on-disk compatibility across versions.  So I think
the opportunity cost of assigning a use to that space is mighty high.
I don't find this idea important enough to justify foreclosing future
uses for the special space.

The real bottom line is this: if you care enough about your data to
be willing to expend a large amount of effort on manual recovery
attempts, why didn't you have a decent backup scheme in place?
There are way too many scenarios where you'll have no hope of doing
any such manual recovery anyway.

			regards, tom lane