Re: toast tables on system catalogs - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: toast tables on system catalogs
Date
Msg-id 201109051701.p85H1Qj16159@momjian.us
Whole thread Raw
In response to Re: toast tables on system catalogs  (Alvaro Herrera <alvherre@commandprompt.com>)
Responses Re: toast tables on system catalogs
List pgsql-hackers
Alvaro Herrera wrote:
> Excerpts from Tom Lane's message of mar mar 01 19:03:35 -0300 2011:
> > Alvaro Herrera <alvherre@alvh.no-ip.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@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +


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