Re: Statistics import and export: difference in statistics of materialized view dumped

On Wed, Mar 12, 2025 at 4:08 AM Jeff Davis <pgsql(at)j-davis(dot)com> wrote:
>
> On Tue, 2025-03-11 at 11:26 -0400, Tom Lane wrote:
> > Right, that was what I was thinking, but hadn't had time to look in
> > detail. The postDataBound dependency isn't real helpful here, we
> > could lose that if we had the data dependency.
>
> Attached a patch.
>
> It's a bit messier than I expected, so I'm open to other suggestions.
> The reason is because materialized view data is also pushed to
> RESTORE_PASS_POST_ACL, so we need to do the same for the statistics
> (otherwise the dependency is just ignored).

I ran my test with this patch (we have to remove 0003 patch in my test
which uses --no-statistics option). It failed with following
differences
@@ -452068,8 +452068,8 @@
SELECT * FROM pg_catalog.pg_restore_relation_stats(
'version', '180000'::integer,
'relation', 'public.mvtest_aa'::regclass,
- 'relpages', '2'::integer,
- 'reltuples', '1'::real,
+ 'relpages', '0'::integer,
+ 'reltuples', '-1'::real,
'relallvisible', '0'::integer
);
--
@@ -452097,8 +452097,8 @@
SELECT * FROM pg_catalog.pg_restore_relation_stats(
'version', '180000'::integer,
'relation', 'public.mvtest_tm_type'::regclass,
- 'relpages', '2'::integer,
- 'reltuples', '3'::real,
+ 'relpages', '0'::integer,
+ 'reltuples', '-1'::real,
'relallvisible', '0'::integer
);
--
@@ -452111,8 +452111,8 @@
SELECT * FROM pg_catalog.pg_restore_relation_stats(
'version', '180000'::integer,
'relation', 'public.mvtest_tvmm_expr'::regclass,
- 'relpages', '2'::integer,
- 'reltuples', '1'::real,
+ 'relpages', '0'::integer,
+ 'reltuples', '-1'::real,
'relallvisible', '0'::integer
);
--=== stderr ===
=== EOF ===

The previous differences have disappeared but new differences have appeared.

--
Best Wishes,
Ashutosh Bapat