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.
        regards, tom lane