On Thu, May 27, 2021 at 12:11 AM Tom Lane <t...@sss.pgh.pa.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. If it helps, I'd be perfectly fine with having this be an *optional* behavior for CLUSTER or VACUUM FULL, depending on some switch. Or we can devise another way for the user to make it happen. But we shouldn't just be setting a policy that users are not allowed to care whether their data is actually compressed using the compression method they specified. -- Robert Haas EDB: http://www.enterprisedb.com
