Tom Lane wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> That implies a fairly robust and configurable system for adding to and
>> rewriting system catalogs, which today we haven't got.
>
> And we won't ever have, because it's unnecessary and would be impossibly
> complex. We know how to do the catalog update: basically, dump, initdb,
> reload, then move the data in. There are some corner case issues like
> how to preserve toast table OIDs, but the idea that we are going to
> invent a special process for each catalog change is just not reasonable.
Right, the dump+initdb+reload approach works quite well in both
pg_upgrade and pg-migrator. I believe the biggest issue with that ATM is
supporting dropped columns, and maybe there's something else, but it's
fairly robust and works across any versions.
-- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com