Horton

Re: race condition in pg_class

Noah Misch <noah@leadboat.com>

View thread
From: Noah Misch <noah@leadboat.com>
To: Alexander Lakhin <exclusion@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, pgsql-hackers@postgresql.org, Tom Lane <tgl@sss.pgh.pa.us>, Smolkin Grigory <smallkeen@gmail.com>, Michael Paquier <michael@paquier.xyz>
Date: 2024-07-04T22:08:16Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Replace tests of ALTER DATABASE RESET TABLESPACE.

  2. meson: Flush stdout in testwrap

  3. Fix catcache invalidation of a list entry that's being built

  4. Stop reading uninitialized memory in heap_inplace_lock().

  5. Fix use of uninitialized value in previous commit.

  6. Back-patch "Refactor code in tablecmds.c to check and process tablespace moves"

  7. Fix data loss at inplace update after heap_update().

  8. For inplace update durability, make heap_update() callers wait.

  9. Warn if LOCKTAG_TUPLE is held at commit, under debug_assertions.

  10. Don't lose partitioned table reltuples=0 after relhassubclass=f.

  11. Fix new assertion for MERGE view_name ... DO NOTHING.

  12. Remove configuration-dependent output from new inplace-inval test.

  13. AccessExclusiveLock new relations just after assigning the OID.

  14. Cope with inplace update making catcache stale during TOAST fetch.

  15. Expand comments and add an assertion in nodeModifyTable.c.

  16. Improve test coverage for changes to inplace-updated catalogs.

  17. Lock before setting relhassubclass on RELKIND_PARTITIONED_INDEX.

  18. Lock owned sequences during ALTER TABLE SET { LOGGED | UNLOGGED }.

  19. Make TAP todo_start effects the same under Meson and prove_check.

  20. Add an injection_points isolation test suite.

  21. Add wait event type "InjectionPoint", a custom type like "Extension".

  22. Create waitfuncs.c for pg_isolation_test_session_is_blocked().

  23. Rework planning and execution of UPDATE and DELETE.

Attachments

On Thu, Jul 04, 2024 at 08:00:00AM +0300, Alexander Lakhin wrote:
> 28.06.2024 08:13, Noah Misch wrote:
> > Pushed. ...
> 
> Please look also at another anomaly, I've discovered.
> 
> An Assert added with d5f788b41 may be falsified with:
> CREATE TABLE t(a int PRIMARY KEY);
> INSERT INTO t VALUES (1);
> CREATE VIEW v AS SELECT * FROM t;
> 
> MERGE INTO v USING (VALUES (1)) AS va(a) ON v.a = va.a
>   WHEN MATCHED THEN DO NOTHING
>   WHEN NOT MATCHED THEN DO NOTHING;
> 
> TRAP: failed Assert("resultRelInfo->ri_TrigDesc"), File: "nodeModifyTable.c", Line: 2891, PID: 1590670

Thanks.  When all the MERGE actions are DO NOTHING, view_has_instead_trigger()
returns true, so we use the wholerow code regardless of the view's triggers or
auto update capability.  The behavior is fine, so I'm fixing the new assertion
and comments with new patch inplace087-merge-DO-NOTHING-v8.patch.  The closest
relevant tests processed zero rows, so they narrowly avoided witnessing this
assertion.