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. regards, tom lane
