Re: Move pg_attribute.attcompression to earlier in struct for reduced size?

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Thu, May 27, 2021 at 12:11 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> AFAIR, there are zero promises about how effective, or when effective,
>> changes in SET STORAGE will be. And the number of complaints about
>> that has also been zero. So I'm not sure why we need to do more for
>> SET COMPRESSION. Especially since I'm unconvinced that recompressing
>> everything just to recompress everything would *ever* be worthwhile.

> I think it is good to have *some* way of ensuring that what you want
> the system to do, it is actually doing. If we have not a single
> operation in the system anywhere that can force recompression, someone
> who actually cares will be left with no option but a dump and reload.
> That is probably both a whole lot slower than something in the server
> itself and also a pretty silly thing to have to tell people to do.

[ shrug... ] I think the history of the SET STORAGE option teaches us
that there is no such requirement, and you're inventing a scenario that
doesn't exist in the real world.

regards, tom lane