Tom Lane wrote: > Magnus Hagander <mag...@hagander.net> writes: > > I haven't actually looked into pg_migrator enough to know how likely > > it is that it'll "just work" going alpha->alpha when there have only > > been "normal" changes? How invasive are the changes that actually > > require pg_migrator to be touched at all? > > To my mind there are three categories of stuff that pg_migrator has to > do: > > * catalog changes (handled by pg_dump/reload) > * on-disk data layout changes (not handled yet anyway) > * random weird unclassifiable stuff > > It's the third category that is the problem. An example from the 8.3 to > 8.4 migration is the need to specially handle sequences because they're > not compatible on-disk. Any pair of releases you might pick is going to > have its own little quirks like that. Our intention (at least as I see > it) is to minimize pg_migrator's complexity by decreeing that any given > release of pg_migrator deals with exactly one pair of PG releases. > I don't think that works if alpha->alpha has to be supported --- in > particular, 8.5alpha1 to 8.5alpha2 might be quite different from what > will be needed later for 8.4 to 8.5, so you would end up with multiple > live branches of pg_migrator, or else a lot of spaghetti code trying to > track which actions to take for a given case. > > The other little problem is who's going to do this work and when. > The alpha-release idea was sold to us on the basis of being a small > amount of incremental work: just tag an alpha release right after > CommitFest and kick it out there. If we're waiting around for someone > to produce and test a compatible pg_migrator, that's not going to be > how it works.
Because the 8.5 is alpha anyway, and because pg_migrator works with current CVS, let's just say it works and wait for someone to report a problem. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + If your life is a hard drive, Christ can be your backup. + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
