On Tue, Feb 25, 2025 at 1:22 PM Jeff Davis <pg...@j-davis.com> wrote:
> On Mon, 2025-02-24 at 12:50 -0500, Tom Lane wrote: > > Also, while working on the attached, I couldn't help forming the > > opinion that we'd be better off to nuke pg_set_attribute_stats() > > from orbit and require people to use pg_restore_attribute_stats(). > > Attached a patch to do so. The docs and tests required substantial > rework, but I think it's for the better now that we aren't trying to do > in-place updates. > > Regards, > Jeff Davis > > All the C code changes make sense to me. Though as an aside, we're going to run into the parameter-ordering problem when it comes to pg_clear_attribute_stats, but that's a (read: my) problem for a later patch. Documentation: + The currently-supported relation statistics are + <literal>relpages</literal> with a value of type + <type>integer</type>, <literal>reltuples</literal> with a value of + type <type>real</type>, and <literal>relallvisible</literal> with a + value of type <type>integer</type>. Could we make this a bullet-list? Same for the required attribute stats and optional attribute stats. I think it would be more eye-catching and useful to people skimming to recall the name of a parameter, which is probably what most people will do after they've read it once to get the core concepts. Question: Do we want to re-compact the oids we consumed in pg_proc.dat? Test cases: We're ripping out a lot of regression tests here. Some of them obviously have no possible pg_restore_* analogs, such as explicitly set NULL values vs omitting the param entirely, but some others may not, especially the ones that test required arg-pairs. Specifically missing are: * regclass not found * attribute is system column * scalars can't have mcelem * mcelem / mcelem freqs mismatch (parts 1 and 2) * scalars can't have elem_count_histogram * cannot set most_common_elems for range type I'm less worried about all the tests of successful import calls, as the pg_upgrade TAP tests kick those tires pretty well. I'm also ok with losing the copies from test to test_clone, those are also covered well by the TAP tests. I'd feel better if we adapted the above tests from set-tests to restore-tests, as the TAP suite doesn't really cover intentionally bad stats.
