Re: \dt+ sizes don't include TOAST data

Tom Lane wrote:
> Greg Smith <greg@2ndquadrant.com> writes:
> > Florian Weimer wrote:
> >> The sizes displayed by \dt+ in version 8.4.2 do not take TOAST tables
> >> into account, presumably because the pg_relation_size does not reflect
> >> that, either.  I think this is a bit surprising.  From a user
> >> perspective, these are part of the table storage (I understand that
> >> the indices might be a different story, but TOAST table are a fairly
> >> deep implementation detail and should perhaps be hidden here).
>
> > As of last week there's a new pg_table_size available that does what you
> > want here:
> > http://archives.postgresql.org/pgsql-committers/2010-01/msg00288.php
>
> > I don't believe \dt+ has been updated yet to use that though; that's
> > worth considering for a minute, not sure anybody thought about it yet.
>
> We could only use pg_table_size against a backend >= 9.0, which would
> mean that the displayed results mean something different depending on
> which backend version psql is being used with.  That's not necessarily
> a deal-breaker, but it does seem a bit evil.

Perhaps we can emulate pg_table_size on earlier server versions, using a
query which provides the sum of table plus toast items.  It would be a
bit slower, but the normal case of using the same server version would
be fast.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.