On Sat, Jan 16, 2021 at 12:03:19PM -0500, Tom Lane wrote: > Noah Misch <n...@leadboat.com> writes: > > On Wed, Jan 13, 2021 at 10:28:26AM -0500, Tom Lane wrote: > >> So a non-rewriting conversion would only be possible if local time is > >> identical to UTC; which is true for few enough people that nobody has > >> bothered with attempting the optimization. > > > PostgreSQL 12 and later do have that optimization. Example DDL: > > https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=3c59263#patch4 > > Ah, I'd forgotten about that patch (obviously). It is a kluge, without > a doubt, since it has to hard-wire knowledge about the behavior of two > specific conversions into what ought to be general-purpose code. But > I guess it is useful often enough to justify its existence. > > I wonder whether it'd be worth moving this logic into a planner support > function attached to those conversion functions? I wouldn't bother > right now, but if somebody else comes along with a similar proposal, > we should think hard about that.
Yes.
