Re: recovering from "found xmin ... from before relfrozenxid ..."

Robert Haas <robertmhaas@gmail.com> writes:
> Oh, I hadn't realized that limitation. That would be good to fix. It
> would be even better, I think, if we could have VACUUM proceed with
> the rest of vacuuming the table, emitting warnings about each
> instance, instead of blowing up when it hits the first bad tuple, but
> I think you may have told me sometime that doing so would be, uh, less
> than straightforward. We probably should refuse to update
> relfrozenxid/relminmxid when this is happening, but I *think* it would
> be better to still proceed with dead tuple cleanup as far as we can,
> or at least have an option to enable that behavior. I'm not positive
> about that, but not being able to complete VACUUM at all is a FAR more
> urgent problem than not being able to freeze, even though in the long
> run the latter is more severe.

+1 for proceeding in this direction, rather than handing users tools
that they *will* hurt themselves with.

The more that I think about it, the more I think that the proposed
functions are tools for wizards only, and so I'm getting hesitant
about having them in contrib at all.  We lack a better place to
put them, but that doesn't mean they should be there.

            regards, tom lane