Tom Lane wrote:
> Oh, I see what you're trying to do. The answer is no. We're not going
> to totally destroy back-portability of dumps, especially not for a
> problem that won't even affect most people (negative intervals are
> hardly common).
Similarly I wonder if pg_dump should add a "fail if version < 8.2" right
before it outputs SET standard_conforming_strings = on;
which IMHO is far more common than negative intervals and AFAICT
has the same risk.
For intervals, we would only add the fail code if intervalstyle was set
to one of the new interval styles (if the ISO8601 interval's accepted
it'll have the problem too).
For backward compatible patches, they could still have their
GUC settingse specify standard_conforming_strings and interval_style
values that are supported by whichever versions they want to support.