Re: pg_dump: ALTER INDEX SET STATISTICS missing for index-backed constraints

> On Jul 14, 2026, at 20:45, Zsolt Parragi <zsolt(dot)parragi(at)percona(dot)com> wrote:
>
> Hello hackers,
>
> I noticed this while reviewing the pg_get_tale_ddl patch and looking
> for inconsistencies compared to pg_dump.
>
> It seems like pg_dump emits SET STATISTICS for most cases since 2018
> (e4fca461), but it was missed in this case:
>
> CREATE TABLE t (a int, b int);
> ALTER TABLE t ADD CONSTRAINT name EXCLUDE USING gist ((a+b) WITH =);
> ALTER INDEX name ALTER COLUMN 1 SET STATISTICS 900;
>
> The last statement was missing from the pg_dump output.
>
> Attached patch fixes it and adds a test case.
> <0001-Dump-index-column-statistics-for-index-backed-constr.patch>

The patch looks good to me overall. My only nit is that it adds more dup code to dumpIndex(). Maybe we could factor that out into a small helper function shared by dumpIndex() and dumpConstraint().

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/