Re: pgsql: Prevent CLUSTER from decreasing a relation's relfrozenxid.

Alvaro Herrera <alvherre@commandprompt.com> writes:
> I don't think it explains the reported bug, though; this is all new in
> 8.3.

No, it certainly doesn't explain the problem JD reported --- not only is
it new code in 8.3, but the symptom is backwards from what was reported
(main table's relfrozenxid older than toast table's, instead of newer).

It's barely possible that the symptom is actually the same and there was
a wraparound issue in there too, but I suspect that what JD really had
there was some kind of PITR tracking problem.  Can't think what though.
When we first got the report I went trolling for places that might fail
to WAL-log a relfrozenxid update, but I couldn't find anything.

            regards, tom lane