On Mon, Jan 27, 2025 at 9:05 AM jian he <jian.universal...@gmail.com> wrote:
> On Tue, Jan 21, 2025 at 7:31 AM Jeff Davis <pg...@j-davis.com> wrote: > > > > On Mon, 2025-01-20 at 16:45 -0500, Corey Huinker wrote: > > > > > > What I struggle to understand is how that purpose isn't served better > > > by statistics being in SECTION_NONE like COMMENTs are, so that they > > > are imported immediately after the object that they reference. > > > > Tom, you expressed the strongest opinions on this point, can you expand > > a bit? > > > > If I understand correctly: > > > > * We strongly want stats to be exported by default[1]. > > > > * Adding a SECTION_STATS could work, but would be non-trivial and might > > break expectations about the set of sections available[2]. > > > > * SECTION_NONE doesn't seem right. There would be no way to get the > > stats using --section. Also, if there is no section boundary for the > > stats, then couldn't they appear in a surprising order? > > > > * I'm not sure about placing stats in SECTION_POST_DATA. That doesn't > > seem terrible to me, but not great either. > > > > index is on SECTION_POST_DATA. > To dump all the statistics, we have to go through SECTION_POST_DATA. > place it there would be more convenient. > That would be the simpler solution, but those statistics may come in handy for refreshing mviews, so some may want table stats to stay in SECTION_DATA. > > Tomas Vondra also mentioned this on [1] > [1] > https://www.postgresql.org/message-id/bf724b21-914a-4497-84e3-49944f9776f6%40enterprisedb.com > > > * I'm also not 100% sure about the flags. The default should dump the > > stats, of course. And I like the idea of allowing any combination of > > schema, data and stats to be exported. But that leaves a wrinkle for -- > > data-only, which (as of v38) does not dump stats, because stats are a > > third kind of thing. Perhaps stats should be expressed as a subtype of > > data somehow, but I'm not sure exactly how. > > > if we have --data-only, --schema-only, --statistics-only, three options, > then > --data-only also dump statistics would be unintuitive? > Yeah, I think the codebase and the user flags both have confusing bits where the not-wanting of one type of thing was specified by only-wanting the other thing, and those choices fall apart when the binary becomes trinary.
