Re: Pg_upgrade and toast tables bug discovered

On Wed, Jul 9, 2014 at 12:09 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>> To me, that sounds vastly more complicated and error-prone than
>> forcing the TOAST tables to be added in a second pass as Andres
>> suggested.
>>
>> But I just work here.
>
> Agreed. I am now thinking we could harness the code that already exists
> to optionally add a TOAST table as part of ALTER TABLE ADD COLUMN. We
> would just need an entry point to call it from pg_upgrade, either via an
> SQL command that checks (and hopefully doesn't do anything else), or a C
> function that does it, e.g. VACUUM would be trivial to run on every
> database, but I don't think it tests that; is _could_ in binary_upgrade
> mode. However, the idea of having a C function plug into the guts of
> the server and call internal functions makes me uncomforable.

Well, pg_upgrade_support's charter is basically to provide access to
the guts of the server in ways we wouldn't normally allow; all that
next-OID stuff is basically exactly that. So I don't think this is
such a big deal. It needs to be properly commented, of course.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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