postgresql/src/test
Andres Freund 7c38ef2a5d Fix temporary object cleanup failing due to toast access without snapshot.
When cleaning up temporary objects during process exit the cleanup could fail
with:
  FATAL: cannot fetch toast data without an active snapshot

The bug is caused by RemoveTempRelationsCallback() not setting up a
snapshot. If an object with toasted catalog data needs to be cleaned up,
init_toast_snapshot() could fail with the above error.

Most of the time however the the problem is masked due to cached catalog
snapshots being returned by GetOldestSnapshot(). But dropping an object can
cause catalog invalidations to be emitted. If no further catalog accesses are
necessary between the invalidation processing and the next toast datum
deletion, the bug becomes visible.

It's easy to miss this bug because it typically happens after clients
disconnect and the FATAL error just ends up in the log.

Luckily temporary table cleanup at the next use of the same temporary schema
or during DISCARD ALL does not have the same problem.

Fix the bug by pushing a snapshot in RemoveTempRelationsCallback(). Also add
isolation tests for temporary object cleanup, including objects with toasted
catalog data.

A future HEAD only commit will add an assertion trying to make this more
visible.

Reported-By: Miles Delahunty
Author: Andres Freund
Discussion: https://postgr.es/m/CAOFAq3BU5Mf2TTvu8D9n_ZOoFAeQswuzk7yziAb7xuw_qyw5gw@mail.gmail.com
Backpatch: 10-
2022-02-21 08:57:34 -08:00
..
authentication Replace Test::More plans with done_testing 2022-02-11 20:54:44 +01:00
examples Update copyright for 2022 2022-01-07 19:04:57 -05:00
isolation Fix temporary object cleanup failing due to toast access without snapshot. 2022-02-21 08:57:34 -08:00
kerberos Replace Test::More plans with done_testing 2022-02-11 20:54:44 +01:00
ldap Replace Test::More plans with done_testing 2022-02-11 20:54:44 +01:00
locale Update copyright for 2022 2022-01-07 19:04:57 -05:00
mb Fix MB regression tests for WAL-logging of hash indexes. 2017-03-15 07:25:36 -04:00
modules Remove PostgreSQL::Test::Utils::perl2host completely 2022-02-20 11:51:45 -05:00
perl Remove most msys special processing in TAP tests 2022-02-20 11:51:45 -05:00
recovery Remove most msys special processing in TAP tests 2022-02-20 11:51:45 -05:00
regress Increase hash_mem_multiplier default to 2.0. 2022-02-16 18:41:52 -08:00
ssl Remove PostgreSQL::Test::Utils::perl2host completely 2022-02-20 11:51:45 -05:00
subscription Replace Test::More plans with done_testing 2022-02-11 20:54:44 +01:00
Makefile Revert per-index collation version tracking feature. 2021-05-07 21:10:11 +12:00
README Remove the option to build thread_test.c outside configure. 2020-10-21 12:08:48 -04:00

PostgreSQL tests
================

This directory contains a variety of test infrastructure as well as some of the
tests in PostgreSQL. Not all tests are here -- in particular, there are more in
individual contrib/ modules and in src/bin.

Not all these tests get run by "make check". Check src/test/Makefile to see
which tests get run automatically.

authentication/
  Tests for authentication (but see also below)

examples/
  Demonstration programs for libpq that double as regression tests via
  "make check"

isolation/
  Tests for concurrent behavior at the SQL level

kerberos/
  Tests for Kerberos/GSSAPI authentication and encryption

ldap/
  Tests for LDAP-based authentication

locale/
  Sanity checks for locale data, encodings, etc

mb/
  Tests for multibyte encoding (UTF-8) support

modules/
  Extensions used only or mainly for test purposes, generally not suitable
  for installing in production databases

perl/
  Infrastructure for Perl-based TAP tests

recovery/
  Test suite for recovery and replication

regress/
  PostgreSQL's main regression test suite, pg_regress

ssl/
  Tests to exercise and verify SSL certificate handling

subscription/
  Tests for logical replication