Robert Haas <robertmh...@gmail.com> writes: > On Fri, Nov 9, 2012 at 3:31 PM, Simon Riggs <si...@2ndquadrant.com> wrote: >> So what we're talking about here is a new mode for COPY, that when >> requested will pre-freeze tuples when loading into a newly >> created/truncated table. If the table isn't newly created/truncated >> then we'll just ignore it and continue. I see no need to throw an >> error, since that will just cause annoying usability issues.
> Actually, why not just have it work always? If people want to load > frozen tuples into a table that's not newly created/truncated, why not > let them? Sure, there could be MVCC violations, but as long as the > behavior is opt-in, who cares? I think it'd be useful to a lot of > people. I thought about that too, but there's a big problem. It wouldn't be just MVCC that would be broken, but transactional integrity: if the COPY fails partway through, the already-loaded rows still look valid. The new-file requirement provides a way to roll them back. I'm willing to have an option that compromises MVCC semantics transiently, but giving up transactional integrity seems a bit much. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers