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

Re: toast tables on system catalogs

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: toast tables on system catalogs
Date: 2011-09-05 17:01:26
Message-ID: 201109051701.p85H1Qj16159@momjian.us (view raw or flat)
Thread:
Lists: pgsql-hackers
Alvaro Herrera wrote:
> Excerpts from Tom Lane's message of mar mar 01 19:03:35 -0300 2011:
> > Alvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> writes:
> > > Strangely, we made pg_database have a toast table, and the only reason
> > > for this is datacl.  Should we create toast tables for the remaining
> > > catalogs?
> > 
> > As I commented on your blog, this is nonsense.  pg_database has a TOAST
> > table becase we thought it might need one for datconfig[].  Now that
> > that's gone, it'd be consistent to remove the toast table, but it didn't
> > occur to us to do that.
> 
> Yeah, it occured to me to troll the git logs just after sending the
> email and I promptly noticed the bug in my conclusion -- there was no
> datacl back then; and pg_db_role_settings is very new.
> 
> > aclitem entries wide enough to need toasting are going to suck for all
> > sorts of reasons (IIRC there are some O(N^2) algorithms in there, not
> > to mention the cost of pulling in entries from a toast table on every
> > access) so I am not excited about encouraging people to use them.
> 
> I agree on not supporting large numbers of privileges, though the error
> message leaves a bit to be desired.
> 
> Should we remove the toast table declaration for pg_database?
> 
> (BTW with the relmapper mechanism, do we still need to declare the toast
> table OIDs?)

Did we decide on this?  Is it a TODO?

-- 
  Bruce Momjian  <bruce(at)momjian(dot)us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +

In response to

Responses

pgsql-hackers by date

Next:From: Tom LaneDate: 2011-09-05 17:06:52
Subject: Re: Is the attribute options cache actually worth anything?
Previous:From: Bruce MomjianDate: 2011-09-05 16:56:33
Subject: Re: Is the attribute options cache actually worth anything?

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