Previously, these characters could cause problems when passed through
shell commands, and were flagged with a comment in string_utils.c
suggesting they be rejected in a future major release.
The affected commands are CREATE DATABASE, CREATE ROLE, CREATE TABLESPACE,
ALTER DATABASE RENAME, ALTER ROLE RENAME, and ALTER TABLESPACE RENAME.
Also add a pg_upgrade check to detect these invalid names in clusters
being upgraded from pre-v19 versions, producing a report file listing
any offending objects that must be renamed before upgrading.
Tests have been modified accordingly.
Author: Mahendra Singh Thalor <mahi6run@gmail.com>
Reviewed-By: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-By: Andrew Dunstan <andrew@dunslane.net>
Reviewed-By: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-By: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-By: Srinath Reddy <srinath2133@gmail.com>
Discussion: https://postgr.es/m/CAKYtNApkOi4FY0S7+3jpTqnHVyyZ6Tbzhtbah-NBbY-mGsiKAQ@mail.gmail.com
This new option instructs vacuumdb to print, but not execute, the
VACUUM and ANALYZE commands that would've been sent to the server.
Author: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/CADkLM%3DckHkX7Of5SrK7g0LokPUwJ%3Dkk8JU1GXGF5pZ1eBVr0%3DQ%40mail.gmail.com
The TAP tests whose ok() calls are changed in this commit were relying
on perl operators, rather than equivalents available in Test::More. For
example, rather than the following:
ok($data =~ qr/expr/m, "expr matching");
ok($data !~ qr/expr/m, "expr not matching");
The new test code uses this equivalent:
like($data, qr/expr/m, "expr matching");
unlike($data, qr/expr/m, "expr not matching");
A huge benefit of the new formulation is that it is possible to know
about the values we are checking if a failure happens, making debugging
easier, should the test runs happen in the buildfarm, in the CI or
locally.
This change leads to more test code overall as perltidy likes to make
the code pretty the way it is in this commit.
Author: Sadhuprasad Patro <b.sadhu@gmail.com>
Discussion: https://postgr.es/m/CAFF0-CHhwNx_Cv2uy7tKjODUbeOgPrJpW4Rpf1jqB16_1bU2sg@mail.gmail.com
Previously, vacuumdb --analyze-only issued VACUUM (ONLY_DATABASE_STATS)
at the end. Since --analyze-only is meant to update optimizer statistics only,
this extra VACUUM command is unnecessary.
This commit prevents vacuumdb --analyze-only from running that redundant
VACUUM command.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Mircea Cadariu <cadariu.mircea@gmail.com>
Discussion: https://postgr.es/m/CAHGQGwEqHGa-k=wbRMucUVihHVXk4NQkK94GNN=ym9cQ5HBSHg@mail.gmail.com
Statistics aren't created for virtual generated columns, so
"vacuumdb --missing-stats-only" always chooses to analyze tables
that have them. To fix, modify vacuumdb's query for retrieving
relations that are missing statistics to exclude those columns.
Oversight in commit edba754f05.
Author: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/20250820104226.8ba51e43164cd590b863ce41%40sraoss.co.jp
Backpatch-through: 18
vacuumdb should follow the behavior of the underlying VACUUM and ANALYZE
commands. When --analyze-only is used, it ought to analyze regular tables,
materialized views, and partitioned tables, just as ANALYZE (with no explicit
target tables) does. Otherwise, it should only process regular tables and
materialized views, since VACUUM skips partitioned tables when no targets
are given.
Previously, vacuumdb --analyze-only skipped partitioned tables. This was
inconsistent, and also inconvenient after pg_upgrade, where --analyze-only
is typically used to gather missing statistics.
This commit fixes the behavior so that vacuumdb --analyze-only also processes
partitioned tables. As a result, both vacuumdb --analyze-only and
ANALYZE (with no explicit targets) now analyze regular tables,
partitioned tables, and materialized views, but not foreign tables.
Because this is a nontrivial behavior change, it is applied only to master.
Reported-by: Zechman, Derek S <Derek.S.Zechman@snapon.com>
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Co-authored-by: Mircea Cadariu <cadariu.mircea@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CO1PR04MB8281387B9AD9DE30976966BBC045A%40CO1PR04MB8281.namprd04.prod.outlook.com
This is required before the creation of a new branch. pgindent is
clean, as well as is reformat-dat-files.
perltidy version is v20230309, as documented in pgindent's README.
This commit adds a new --missing-stats-only option that can be used
with --analyze-only or --analyze-in-stages. When this option is
specified, vacuumdb will analyze a relation if it lacks any
statistics for a column, expression index, or extended statistics
object. This new option is primarily intended for use after
pg_upgrade (since it can now retain most optimizer statistics), but
it might be useful in other situations, too.
Author: Corey Huinker <corey.huinker@gmail.com>
Co-authored-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/Z5O1bpcwDrMgyrYy%40nathan
get_parallel_object_list() was trying to serve two masters, and it was
doing a bad job at both. In particular, it treated the given user_list
as an output argument, but only sometimes. This was confusing, and the
two paths through it didn't really have all that much in common, so the
complexity wasn't buying us much. Split it in two:
get_parallel_tables_list() handles the straightforward cases for
schemas, databases and tables, takes one list as argument and returns
another list.
A new function get_parallel_tabidx_list() handles the case for indexes.
This takes a list as argument and outputs two lists, just like
get_parallel_object_list used to do, but now the API is clearer (IMO
anyway). Another difference is that accompanying the list of indexes
now we have a list of tables as an OID list rather than a
fully-qualified table name list. This makes some comparisons easier,
and we don't really need the names of the tables, just their OIDs.
(This requires atooid, which requires <stdlib.h>).
Author: Ranier Vilela <ranier.vf@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAEudQArfqr0-s0VVPSEh=0kgOgBJvFNdGW=xSL5rBcr0WDMQYQ@mail.gmail.com
This commit adds a new --missing-only option that can be used in
conjunction with --analyze-only and --analyze-in-stages. When this
option is specified, vacuumdb will generate ANALYZE commands for a
relation if it is missing any statistics it should ordinarily have.
For example, if a table has statistics for one column but not
another, we will analyze the whole table. A similar principle
applies to extended statistics, expression indexes, and table
inheritance.
Co-authored-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: TODO
Discussion: https://postgr.es/m/Z5O1bpcwDrMgyrYy%40nathan
Some tests are updated to use command_fails_like(), gaining a check for
the error output generated. The test changed in pg_amcheck has come up
after noticing that an incorrect option name still made the test to
pass, while the command failed. The three other tests changed in
src/bin/scripts/ have been noticed by me, in passing.
Author: Dagfinn Ilmari Mannsåker, Michael Paquier
Discussion: https://postgr.es/m/87bjvy50cs.fsf@wibble.ilmari.org
This commit rewrites a good chunk of the command arrays in TAP tests
with a grammar based on the following rules:
- Fat commas are used between option names and their values, making it
clear to both humans and perltidy that values and names are bound
together. This is particularly useful for the readability of multi-line
command arrays, and there are plenty of them in the TAP tests. Most of
the test code is updated to use this style. Some commands used
parenthesis to show the link, or attached values and options in a single
string. These are updated to use fat commas instead.
- Option names are switched to use their long names, making them more
self-documented. Based on a suggestion by Andrew Dunstan.
- Add some trailing commas after the last item in multi-line arrays,
which is a common perl style.
Not all the places are taken care of, but this covers a very good chunk
of them.
Author: Dagfinn Ilmari Mannsåker
Reviewed-by: Michael Paquier, Peter Smith, Euler Taveira
Discussion: https://postgr.es/m/87jzc46d8u.fsf@wibble.ilmari.org
The current code can have pg_isready unexpectedly succeed if there is a
server running on the default port. To avoid this we delay running the
test until after a node has been created but before it starts, and then
use that node's port, so we are fairly sure there is nothing running on
the port.
Backpatch to all live branches.
Run pgindent, pgperltidy, and reformat-dat-files.
The pgindent part of this is pretty small, consisting mainly of
fixing up self-inflicted formatting damage from patches that
hadn't bothered to add their new typedefs to typedefs.list.
In order to keep it from making anything worse, I manually added
a dozen or so typedefs that appeared in the existing typedefs.list
but not in the buildfarm's list. Perhaps we should formalize that,
or better find a way to get those typedefs into the automatic list.
pgperltidy is as opinionated as always, and reformat-dat-files too.
When specifying the createdb strategy, the documentation suggests valid
options are FILE_COPY and WAL_LOG, but the code does case-sensitive
comparison and accepts only "file_copy" and "wal_log" as valid.
Fixed by doing a case-insensitive comparison using pg_strcasecmp(), same
as for other string parameters nearby.
While at it, apply fmtId() to a nearby "locale_provider". This already
did the comparison in case-insensitive way, but the value would not be
double-quoted, confusing the parser and the error message.
Backpatch to 15, where the strategy was introduced.
Backpatch-through: 15
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/90c6913a-1dd2-42b4-8365-ce3b09c39b17@enterprisedb.com
Straight-forward index-level REINDEX is not supported with multiple jobs as
we cannot control the concurrent processing of multiple indexes depending on
the same relation. Instead, we dedicate the whole table to certain reindex
job. Thus, if indexes in the lists belong to different tables, that gives us
a fair level of parallelism.
This commit teaches get_parallel_object_list() to fetch table names for
indexes in the case of index-level REINDEX. The same tables are grouped
together in the output order, and the list of indexes is also rebuilt to
match that order. Later during processingof that list, we push indexes
belonging to the same table into the same job.
Discussion: https://postgr.es/m/CACG%3DezZU_VwDi-1PN8RUSE6mcYG%2BYx1NH_rJO4%2BKe-mKqLp%3DNw%40mail.gmail.com
Author: Maxim Orlov, Svetlana Derevyanko, Alexander Korotkov
Reviewed-by: Michael Paquier
The builtin C.UTF-8 locale has similar semantics to the libc locale of
the same name. That is, code point sort order (fast, memcmp-based)
combined with Unicode semantics for character operations such as
pattern matching, regular expressions, and
LOWER()/INITCAP()/UPPER(). The character semantics are based on
Unicode simple case mappings.
The builtin provider's C.UTF-8 offers several important advantages
over libc:
* faster sorting -- benefits from additional optimizations such as
abbreviated keys and varstrfastcmp_c
* faster case conversion, e.g. LOWER(), at least compared with some
libc implementations
* available on all platforms with identical semantics, and the
semantics are stable, testable, and documentable within a given
Postgres major version
Being based on memcmp, the builtin C.UTF-8 locale does not offer
natural language sort order. But it is an improvement for most use
cases that might otherwise use libc's "C.UTF-8" locale, as well as
many use cases that use libc's "C" locale.
Discussion: https://postgr.es/m/ff4c2f2f9c8fc7ca27c1c24ae37ecaeaeaff6b53.camel%40j-davis.com
Reviewed-by: Daniel Vérité, Peter Eisentraut, Jeremy Schneider
New provider for collations, like "libc" or "icu", but without any
external dependency.
Initially, the only locale supported by the builtin provider is "C",
which is identical to the libc provider's "C" locale. The libc
provider's "C" locale has always been treated as a special case that
uses an internal implementation, without using libc at all -- so the
new builtin provider uses the same implementation.
The builtin provider's locale is independent of the server environment
variables LC_COLLATE and LC_CTYPE. Using the builtin provider, the
database collation locale can be "C" while LC_COLLATE and LC_CTYPE are
set to "en_US", which is impossible with the libc provider.
By offering a new builtin provider, it clarifies that the semantics of
a collation using this provider will never depend on libc, and makes
it easier to document the behavior.
Discussion: https://postgr.es/m/ab925f69-5f9d-f85e-b87c-bd2a44798659@joeconway.com
Discussion: https://postgr.es/m/dd9261f4-7a98-4565-93ec-336c1c110d90@manitou-mail.org
Discussion: https://postgr.es/m/ff4c2f2f9c8fc7ca27c1c24ae37ecaeaeaff6b53.camel%40j-davis.com
Reviewed-by: Daniel Vérité, Peter Eisentraut, Jeremy Schneider
Presently, reindexdb's --table, --schema, --index, and --system
options cannot be used together with --all, i.e., you cannot
specify objects to process in all databases. This commit removes
this unnecessary restriction. Furthermore, it removes the
restriction that --system cannot be used with --table, --schema,
and --index. There is no such restriction for the latter options,
and there is no technical reason to disallow these combinations.
Reviewed-by: Kyotaro Horiguchi, Dean Rasheed
Discussion: https://postgr.es/m/20230628232402.GA1954626%40nathanxps13
Presently, clusterdb's --table option cannot be used together with
--all, i.e., you cannot specify tables to process in all databases.
This commit removes this unnecessary restriction. In passing,
change the synopsis in the documentation to use "[option...]"
instead of "[--verbose | -v]". There are other general-purpose
options (e.g., --quiet and --echo), but the synopsis currently only
lists --verbose.
Reviewed-by: Kyotaro Horiguchi, Dean Rasheed
Discussion: https://postgr.es/m/20230628232402.GA1954626%40nathanxps13
Presently, vacuumdb's --table, --schema, and --exclude-schema
options cannot be used together with --all, i.e., you cannot
specify tables or schemas to process in all databases. This commit
removes this unnecessary restriction, thus enabling potentially
useful commands like "vacuumdb --all --schema pg_catalog".
Reviewed-by: Kyotaro Horiguchi, Dean Rasheed
Discussion: https://postgr.es/m/20230628232402.GA1954626%40nathanxps13
Some of the TAP tests have been historically setting the environment
variable PGDATABASE to 'postgres', which is not needed because
PostgreSQL::Test::Cluster already sets it when initialized. This commit
removes these explicit setups.
Note that the dependency of cluster -a with PGDATABASE (from
1caef31d9e) is still documented.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACXLAz5dW3ZP+Fec8g6jQMMmDyCVT+qdbye2h7QJJmhsdw@mail.gmail.com
There are a lot of Perl scripts in the tree, mostly code generation
and TAP tests. Occasionally, these scripts produce warnings. These
are probably always mistakes on the developer side (true positives).
Typical examples are warnings from genbki.pl or related when you make
a mess in the catalog files during development, or warnings from tests
when they massage a config file that looks different on different
hosts, or mistakes during merges (e.g., duplicate subroutine
definitions), or just mistakes that weren't noticed because there is a
lot of output in a verbose build.
This changes all warnings into fatal errors, by replacing
use warnings;
by
use warnings FATAL => 'all';
in all Perl files.
Discussion: https://www.postgresql.org/message-id/flat/06f899fd-1826-05ab-42d6-adeb1fd5e200%40eisentraut.org
When specifying multiple schemas to exclude with -N parameters, none
of the schemas are actually excluded (a single -N worked as expected).
This fixes the catalog query to handle multiple exclusions and adds a
test for this case.
Backpatch to v16 where this was introduced.
Author: Nathan Bossart <nathandbossart@gmail.com>
Author: Kuwamura Masaki <kuwamura@db.is.i.nagoya-u.ac.jp>
Reported-by: Kuwamura Masaki <kuwamura@db.is.i.nagoya-u.ac.jp>
Discussion: https://postgr.es/m/CAMyC8qp9mXPQd5D6s6CJxvmignsbTqGZwDDB6VYJOn1A8WG38w@mail.gmail.com
Backpatch-through: 16
Until now, when DROP DATABASE got interrupted in the wrong moment, the removal
of the pg_database row would also roll back, even though some irreversible
steps have already been taken. E.g. DropDatabaseBuffers() might have thrown
out dirty buffers, or files could have been unlinked. But we continued to
allow connections to such a corrupted database.
To fix this, mark databases invalid with an in-place update, just before
starting to perform irreversible steps. As we can't add a new column in the
back branches, we use pg_database.datconnlimit = -2 for this purpose.
An invalid database cannot be connected to anymore, but can still be
dropped.
Unfortunately we can't easily add output to psql's \l to indicate that some
database is invalid, it doesn't fit in any of the existing columns.
Add tests verifying that a interrupted DROP DATABASE is handled correctly in
the backend and in various tools.
Reported-by: Evgeny Morozov <postgresql3@realityexists.net>
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20230509004637.cgvmfwrbht7xm7p6@awork3.anarazel.de
Discussion: https://postgr.es/m/20230314174521.74jl6ffqsee5mtug@awork3.anarazel.de
Backpatch: 11-, bug present in all supported versions
Unlike the other implementations of getopt_long() I could find, the
in-tree implementation does not reorder non-options to the end of
argv. Instead, it returns -1 as soon as the first non-option is
found, even if there are other options listed afterwards. By
moving non-options to the end of argv, getopt_long() can parse all
specified options and return -1 when only non-options remain.
This quirk is periodically missed by hackers (e.g., 869aa40a27,
ffd398021c, and d9ddc50baf). This commit introduces the
aforementioned non-option reordering behavior to the in-tree
getopt_long() implementation.
Special thanks to Noah Misch for his help verifying behavior on
AIX.
Reviewed-by: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/20230609232257.GA121461%40nathanxps13
Run pgindent and pgperltidy. It seems we're still some ways
away from all committers doing this automatically. Now that
we have a buildfarm animal that will whine about poorly-indented
code, we'll try to keep the tree more tidy.
Discussion: https://postgr.es/m/3156045.1687208823@sss.pgh.pa.us
For CREATE DATABASE, make LOCALE parameter apply regardless of the
provider used. Also affects initdb and createdb --locale arguments.
Previously, LOCALE (and --locale) only affected the database default
collation when using the libc provider.
Discussion: https://postgr.es/m/1a63084d-221e-4075-619e-6b3e590f673e@enterprisedb.com
Reviewed-by: Peter Eisentraut
While executing maintenance operations (ANALYZE, CLUSTER, REFRESH
MATERIALIZED VIEW, REINDEX, or VACUUM), set search_path to
'pg_catalog, pg_temp' to prevent inconsistent behavior.
Functions that are used for functional indexes, in index expressions,
or in materialized views and depend on a different search path must be
declared with CREATE FUNCTION ... SET search_path='...'.
This change addresses a security risk introduced in commit 60684dd834,
where a role with MAINTAIN privileges on a table may be able to
escalate privileges to the table owner. That commit is not yet part of
any release, so no need to backpatch.
Discussion: https://postgr.es/m/e44327179e5c9015c8dda67351c04da552066017.camel%40j-davis.com
Reviewed-by: Greg Stark
Reviewed-by: Nathan Bossart
2dcd1578c4 left the --role option undocumented, which is
inconsistent with other deprecated options such as pg_dump's
--blobs and --no-blobs. This change adds --role back to
createuser's documentation and usage output and marks it as
deprecated.
Suggested-by: Peter Eisentraut
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/0e85c9e7-4804-1cdb-5a4a-c72c328f9ad8%40enterprisedb.com
This change renames --admin to --with-admin, --role to --member-of,
and --member to --with-member. Many people found the previous
names to be confusing. The --admin and --member options are new in
v16, but --role has been there for a while, so that one has been
kept (but left undocumented) for backward compatibility.
Suggested-by: Peter Eisentraut
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/ZFvVZvQDliIWmOwg%40momjian.us
Run pgindent, pgperltidy, and reformat-dat-files.
This set of diffs is a bit larger than typical. We've updated to
pg_bsd_indent 2.1.2, which properly indents variable declarations that
have multi-line initialization expressions (the continuation lines are
now indented one tab stop). We've also updated to perltidy version
20230309 and changed some of its settings, which reduces its desire to
add whitespace to lines to make assignments etc. line up. Going
forward, that should make for fewer random-seeming changes to existing
code.
Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
This fixes many spelling mistakes in comments, but a few references to
invalid parameter names, function names and option names too in comments
and also some in string constants
Also, fix an #undef that was undefining the incorrect definition
Author: Alexander Lakhin
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/d5f68d19-c0fc-91a9-118d-7c6a5a3f5fad@gmail.com
Previously, the default encoding was derived from the locale when
using libc; while the default was always UTF-8 when using ICU. That
would throw an error when the locale was not compatible with UTF-8.
This commit causes initdb to derive the default encoding from the
locale for both providers. If --no-locale is specified (or if the
locale is C or POSIX), the default encoding will be UTF-8 for ICU
(because ICU does not support SQL_ASCII) and SQL_ASCII for libc.
Per buildfarm failure on system "hoverfly" related to commit
27b62377b4.
Discussion: https://postgr.es/m/d191d5841347301a8f1238f609471ddd957fc47e.camel%40j-davis.com
Add description of which one is the default between two complementary
options of --bypassrls and --replication in the help text and docs. In
correspondence let the command always include the tokens corresponding
to every options of that kind in the SQL command sent to server. Tests
are updated accordingly.
Also fix the checks of some trivalue vars which were using literal zero
for checking default value instead of the enum label TRI_DEFAULT. While
not a bug, since TRI_DEFAULT is defined as zero, fixing improves read-
ability improved readability (and avoid bugs if the enum is changed).
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/20220810.151243.1073197628358749087.horikyota.ntt@gmail.com
Disabling this option is useful to run VACUUM (with or without FULL) on
only the toast table of a relation, bypassing the main relation. This
option is enabled by default.
Running directly VACUUM on a toast table was already possible without
this feature, by using the non-deterministic name of a toast relation
(as of pg_toast.pg_toast_N, where N would be the OID of the parent
relation) in the VACUUM command, and it required a scan of pg_class to
know the name of the toast table. So this feature is basically a
shortcut to be able to run VACUUM or VACUUM FULL on a toast relation,
using only the name of the parent relation.
A new switch called --no-process-main is added to vacuumdb, to work as
an equivalent of PROCESS_MAIN.
Regression tests are added to cover VACUUM and VACUUM FULL, looking at
pg_stat_all_tables.vacuum_count to see how many vacuums have run on
each table, main or toast.
Author: Nathan Bossart
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/20221230000028.GA435655@nathanxps13
VACUUM normally ends by running vac_update_datfrozenxid(), which
requires a scan of pg_class. Therefore, if one attempts to vacuum a
database one table at a time --- as vacuumdb has done since v12 ---
we will spend O(N^2) time in vac_update_datfrozenxid(). That causes
serious performance problems in databases with tens of thousands of
tables, and indeed the effect is measurable with only a few hundred.
To add insult to injury, only one process can run
vac_update_datfrozenxid at the same time per DB, so this behavior
largely defeats vacuumdb's -j option.
Hence, invent options SKIP_DATABASE_STATS and ONLY_DATABASE_STATS
to allow applications to postpone vac_update_datfrozenxid() until the
end of a series of VACUUM requests, and teach vacuumdb to use them.
Per bug #17717 from Gunnar L. Sadly, this answer doesn't seem
like something we'd consider back-patching, so the performance
problem will remain in v12-v15.
Tom Lane and Nathan Bossart
Discussion: https://postgr.es/m/17717-6c50eb1c7d23a886@postgresql.org
