Обсуждение: Inconsistency in owner assignment between INDEX and STATISTICS

Hi,

I'd like to raise a small consistency issue between how INDEX and extended STATISTICS handle object ownership, and ask whether aligning them would be desirable.

Current behavior (tested on REL_17_STABLE):

- When a superuser creates an INDEX on another user's table, the index is owned by the *table owner* (see catalog/index.c: index relation's relowner is set from the heap relation's relowner).
- When a superuser creates STATISTICS on another user's table, the statistics object is owned by the *current user* (statscmds.c: stxowner = GetUserId()).

So in a scenario where a DBA creates both an index and extended statistics on a user's table, the table owner can DROP the index (because they own it) but cannot DROP the statistics object (they get "does not exist" when lacking ownership, which hides the real permission issue). That can cause operational friction in multi-tenant or shared-schema setups (e.g. the table owner cannot drop the statistics to resolve dependency issues before altering the table).

Reproduction (as superuser, then as table owner):

  CREATE SCHEMA shared_schema;
  CREATE USER bob;
  GRANT USAGE, CREATE ON SCHEMA shared_schema TO bob;

  SET ROLE bob;
  CREATE TABLE shared_schema.bob_table (a int, b int);
  RESET ROLE;

  CREATE INDEX idx_bob ON shared_schema.bob_table(a);
  CREATE STATISTICS stat_bob ON a, b FROM shared_schema.bob_table;

  SELECT 'INDEX', c.relname, pg_get_userbyid(c.relowner) FROM pg_index i
    JOIN pg_class c ON c.oid = i.indexrelid
    WHERE indrelid = 'shared_schema.bob_table'::regclass
  UNION ALL
  SELECT 'STATISTICS', stxname, pg_get_userbyid(stxowner) FROM pg_statistic_ext
    WHERE stxrelid = 'shared_schema.bob_table'::regclass;
  -- INDEX owner = bob, STATISTICS owner = superuser

  SET ROLE bob;
  DROP INDEX shared_schema.idx_bob;        -- succeeds
  DROP STATISTICS shared_schema.stat_bob;  -- ERROR: statistics object "..." does not exist

I'm not sure if the current STATISTICS ownership behavior was intentional. If it wasn't, would it make sense to assign the statistics object's owner to the relation owner (same as INDEX) for consistency and to avoid the above scenario?

Thanks for your time.

Gentle ping on this thread — any thoughts or concerns about the
proposed alignment?

Thanks.

On Sat, Feb 14, 2026 at 5:48 PM Shin Berg <sjh910805@gmail.com> wrote:

Hi,

I'd like to raise a small consistency issue between how INDEX and extended STATISTICS handle object ownership, and ask whether aligning them would be desirable.

Current behavior (tested on REL_17_STABLE):

- When a superuser creates an INDEX on another user's table, the index is owned by the *table owner* (see catalog/index.c: index relation's relowner is set from the heap relation's relowner).
- When a superuser creates STATISTICS on another user's table, the statistics object is owned by the *current user* (statscmds.c: stxowner = GetUserId()).

So in a scenario where a DBA creates both an index and extended statistics on a user's table, the table owner can DROP the index (because they own it) but cannot DROP the statistics object (they get "does not exist" when lacking ownership, which hides the real permission issue). That can cause operational friction in multi-tenant or shared-schema setups (e.g. the table owner cannot drop the statistics to resolve dependency issues before altering the table).

Reproduction (as superuser, then as table owner):

  CREATE SCHEMA shared_schema;
  CREATE USER bob;
  GRANT USAGE, CREATE ON SCHEMA shared_schema TO bob;

  SET ROLE bob;
  CREATE TABLE shared_schema.bob_table (a int, b int);
  RESET ROLE;

  CREATE INDEX idx_bob ON shared_schema.bob_table(a);
  CREATE STATISTICS stat_bob ON a, b FROM shared_schema.bob_table;

  SELECT 'INDEX', c.relname, pg_get_userbyid(c.relowner) FROM pg_index i
    JOIN pg_class c ON c.oid = i.indexrelid
    WHERE indrelid = 'shared_schema.bob_table'::regclass
  UNION ALL
  SELECT 'STATISTICS', stxname, pg_get_userbyid(stxowner) FROM pg_statistic_ext
    WHERE stxrelid = 'shared_schema.bob_table'::regclass;
  -- INDEX owner = bob, STATISTICS owner = superuser

  SET ROLE bob;
  DROP INDEX shared_schema.idx_bob;        -- succeeds
  DROP STATISTICS shared_schema.stat_bob;  -- ERROR: statistics object "..." does not exist

I'm not sure if the current STATISTICS ownership behavior was intentional. If it wasn't, would it make sense to assign the statistics object's owner to the relation owner (same as INDEX) for consistency and to avoid the above scenario?

Thanks for your time.

Shin Berg <sjh910805@gmail.com> writes:
> Thank you for the detailed feedback, Amit.
> You're right on both points. I had been comparing STATISTICS against INDEX
> and treating the difference as an inconsistency, but as you point out,
> INDEX ownership is special — it's tied to the table and intentionally not
> user-adjustable. STATISTICS follows the same ownership model as VIEW (the
> creator becomes the owner), which is consistent and by design.

One point that was not mentioned is that while indexes are necessarily
tied to a single table, statistics objects might not always be.  The
long-term hope is to allow statistics on cross-table combinations of
columns, which is why the syntax was intentionally set up to look like
SELECT.  So, just like views, it's reasonable to give them independent
ownership.

                        regards, tom lane