Re: pg_plan_advice

Alexander Lakhin <exclusion@gmail.com>

From: Alexander Lakhin <exclusion@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Lukas Fittl <lukas@fittl.com>, Andrei Lepikhov <lepihov@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2026-04-05T12:00:00Z
Lists: pgsql-hackers
05.04.2026 11:00, Alexander Lakhin wrote:
> I and SQLsmith have discovered one more anomaly (reproduced starting from
> e0e4c132e):
> load 'test_plan_advice';
> select object_type from
>  (select object_type from information_schema.element_types limit 1),
>  lateral
>  (select sum(1) over (partition by a) from generate_series(1, 2) g(a) where false);
>
> triggers an internal error:
> ERROR:  XX000: no rtoffset for plan unnamed_subquery
> LOCATION:  pgpa_plan_walker, pgpa_walker.c:110

And another error, which might be interesting to you:
CREATE EXTENSION tsm_system_time;
CREATE TABLE t(i int);
SELECT 1 FROM (SELECT i FROM t TABLESAMPLE system_time (1000)), LATERAL (SELECT i LIMIT 1);

ERROR:  XX000: plan node has no RTIs: 378
LOCATION:  pgpa_build_scan, pgpa_scan.c:200

Best regards,
Alexander



Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. pg_plan_advice: Fix another unique-semijoin bug.

  2. pg_plan_advice: Export feedback-related definitions.

  3. pg_plan_advice: Fix a bug when a subquery is pruned away entirely.

  4. pg_plan_advice: Add alternatives test to Makefile.

  5. pg_plan_advice: Handle non-repeatable TABLESAMPLE scans.

  6. pg_stash_advice: Allow stashed advice to be persisted to disk.

  7. Add pg_stash_advice contrib module.

  8. pg_plan_advice: Avoid assertion failure with partitionwise aggregate.

  9. pg_plan_advice: Invent DO_NOT_SCAN(relation_identifier).

  10. Add an alternative_plan_name field to PlannerInfo.

  11. pg_plan_advice: Refactor to invent pgpa_planner_info

  12. Respect disabled_nodes in fix_alternative_subplan.

  13. get_memoize_path: Don't exit quickly when PGS_NESTLOOP_PLAIN is unset.

  14. test_plan_advice: Set TAP test priority 50 in meson.build.

  15. pg_plan_advice: Avoid a crash under GEQO.

  16. Test pg_plan_advice using a new test_plan_advice module.

  17. pg_plan_advice: Always install pg_plan_advice.h, and in the right place

  18. pg_plan_advice: Fix failures to accept identifier keywords.

  19. Add pg_plan_advice contrib module.

  20. Allow extensions to mark an individual index as disabled.

  21. Replace get_relation_info_hook with build_simple_rel_hook.

  22. Store information about Append node consolidation in the final plan.

  23. Store information about elided nodes in the final plan.

  24. Store information about range-table flattening in the final plan.

  25. Pass cursorOptions to planner_setup_hook.

  26. Fix PGS_CONSIDER_NONPARTIAL interaction with Materialize nodes.

  27. Fix mistakes in commit 4020b370f214315b8c10430301898ac21658143f

  28. Allow for plugin control over path generation strategies.

  29. Update some comments for fasthash

  30. Allow passing a pointer to GetNamedDSMSegment()'s init callback.

  31. Don't reset the pathlist of partitioned joinrels.

  32. Treat number of disabled nodes in a path as a separate cost metric.