Re: Materialized views WIP patch

On Fri, Feb 15, 2013 at 08:24:16PM -0500, Robert Haas wrote:
> On Fri, Feb 15, 2013 at 8:01 PM, Kevin Grittner <kgrittn(at)ymail(dot)com> wrote:
> > There is one odd aspect to pg_dump, but I think the way it is
> > behaving is the best way to handle it, although I invite other
> > opinions. If you load from pg_dump output, it will try to
> > populated materialized views which were populated on dump, and
> > leave the ones which were not scannable because the contents had
> > not been generated in an empty and unscannable state on restore.
> > That much seems pretty obvious. Where it gets a little tricky is
> > if mva is generated with data, and mvb is generated based on mva.
> > Then mva is truncated. Then you dump. mvb was populated at the
> > time of the dump, but its contents can't be regenerated on restore
> > because mva is not scannable. As the patch currently stands, you
> > get an error on the attempt to REFRESH mvb. I think that's a good
> > thing, but I'm open to arguments to the contrary.
>
> Hmm, anything that means a dump-and-restore can fail seems like a bad
> thing to me. There's nothing outrageous about that scenario. It's
> arguable what state dump-and-restore should leave the new database in,
> but I don't see why it shouldn't work. I predict we'll end up with
> unhappy users if we leave it like this.

pg_upgrade is going to fail on that pg_restore error. :-(

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +