Re: Add starelid, attnum to pg_stats and leverage this in pg_dump

On Sat, Mar 14, 2026 at 05:13:19PM -0400, Corey Huinker wrote:
> "_stable", nice name choice. Rebasing was nonzero but just barely.

Thanks. Here is what I have staged for commit for the next patch in the
series.

> CREATE VIEW pg_stats WITH (security_barrier) AS
> SELECT
> - nspname AS schemaname,
> - relname AS tablename,
> - attname AS attname,
> + n.nspname AS schemaname,
> + c.relname AS tablename,
> + a.attrelid AS tableid,
> + a.attname AS attname,
> + a.attnum AS attnum,

I didn't see why we needed to change the lines for the existing columns, so
I left those parts out.

> CREATE VIEW pg_stats_ext WITH (security_barrier) AS
> SELECT cn.nspname AS schemaname,
> c.relname AS tablename,
> + s.stxrelid AS tableid,
> sn.nspname AS statistics_schemaname,
> s.stxname AS statistics_name,
> + s.oid AS statid,

I went with "statistics_id" to match the naming scheme.

> CREATE VIEW pg_stats_ext_exprs WITH (security_barrier) AS
> SELECT cn.nspname AS schemaname,
> c.relname AS tablename,
> + s.stxrelid AS tableid,
> sn.nspname AS statistics_schemaname,
> s.stxname AS statistics_name,
> + s.oid AS statid,
> pg_get_userbyid(s.stxowner) AS statistics_owner,
> - stat.expr,
> + expr.expr,
> + 0 - expr.ordinality AS expr_attnum,

I left the expr_attnum stuff out. It seems to make this patch quite large
and complicated, we don't plan to use it for the pg_dump patch, and I'm not
sure about showing users a "synthetic attnum" that seems to have no other
point of reference. Would this information be useful in pg_dump somewhere?
I'm curious to hear more about the intent.

> CREATE VIEW stats_import.pg_stats_stable AS
> - SELECT schemaname, tablename, attname, inherited, null_frac, avg_width,
> + SELECT schemaname, tablename, attname, attnum, inherited, null_frac, avg_width,

I didn't see much value in adding attnum here given the size of the changes
to the expected output it produces.

> + <structfield>tableid</structfield> <type>oid</type>
> + (references <link linkend="catalog-pg-attribute"><structname>pg_attribute</structname></link>.<structfield>attrelid</structfield>)

While we might be pulling the OID from pg_attribute in the view, we seem to
point to the true origin for these reference notes elsewhere, so I changed
it to pg_class.oid here.

> + <structfield>tableid</structfield> <type>oid</type>
> + (references <link linkend="catalog-pg-statistic-ext"><structname>pg_statistic_ext</structname></link>.<structfield>stxrelid</structfield>)

... and here.

> + <structfield>tableid</structfield> <type>oid</type>
> + (references <link linkend="catalog-pg-statistic-ext"><structname>pg_statistic_ext</structname></link>.<structfield>stxrelid</structfield>)

... and here.

--
nathan