Skip site navigation (1) Skip section navigation (2)

Re: Applying TOAST to CURRENT

From: The Hermit Hacker <scrappy(at)hub(dot)org>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Jan Wieck <JanWieck(at)Yahoo(dot)com>, Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>, PostgreSQL HACKERS <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Applying TOAST to CURRENT
Date: 2000-05-30 16:11:21
Message-ID: Pine.BSF.4.21.0005301310330.608-100000@thelab.hub.org (view raw or flat)
Thread:
Lists: pgsql-hackers
On Tue, 30 May 2000, Tom Lane wrote:

> JanWieck(at)t-online(dot)de (Jan Wieck) writes:
> >>>> OTOH  I  don't  think  it's  a good thing to try creating
> >>>> these things on  the  fly  the  first  time  needed.  The
> >>>> required catalog changes and file creations introduce all
> >>>> kinds of possible rollback/crash problems, that we  don't
> >>>> want to have here - do we?
> 
> AFAIK we are pretty solid on rolling back table creation, it's just
> rename/drop that have problems.  A worse problem is what if two
> backends both decide they need to create the toast table at the same
> time.  That might be fixable with appropriate locking but it seems
> like there'd be potential for deadlocks.
> 
> > Bruce Momjian wrote:
> >> Well, we could print the message suggesing ALTER TABLE when printing
> >> tuple too large.  Frankly, I don't see a problem in creating the backup
> >> table automatically.  If you are worried about performance, how about
> >> putting it in a subdirectory.
> 
> I agree with Bruce --- the toast table should be created automatically,
> at least if the table contains any potentially-toastable columns.  We
> want this to be as transparent as possible.  I'd rather have auto create
> on-the-fly when first needed, but if that seems too risky then let's
> just make the table when its owning table is created.

have to third this one ... I think it should be totally transparent to the
admin/user ... just create it when the table is created, what's the worst
case scenario?  it never gets used and you waste 16k of disk space?


In response to

Responses

pgsql-hackers by date

Next:From: Bruce MomjianDate: 2000-05-30 16:20:44
Subject: Re: Applying TOAST to CURRENT
Previous:From: Tom LaneDate: 2000-05-30 15:27:19
Subject: Re: Rename database?

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group