Robert Haas <robertmhaas@gmail.com> writes:
> With respect to this chunk:
> + * We do not need to go through this dance for temp relations, though, because
> + * we never make WAL entries for temp rels, and so a temp rel poses no threat
> + * to the health of a regular rel that has taken over its relfilenode number.
> ...I would say that a clearer way to put this is that temporary
> relations use a different file naming convention than permanent
> relations and therefore there can never be any confusion between the
> two.
Yeah, that's an entirely independent reason why there's probably no
issue in recent releases. The rationale as stated is back-patchable
to earlier releases, though.
BTW, I wonder whether the code that checks for relfilenode conflict
when selecting a pg_class or relfilenode OID tries both file naming
conventions? If not, should we make it do so?
regards, tom lane