One is about subqueries becoming joins and the other is about optimizing
LIMIT by improving startup cost.
Reported-by: Andy Fan
Discussion: https://postgr.es/m/87h6f4ncc6.fsf@163.com
Reviewed-by: David Rowley
Backpatch-through: master
Presently, when this function is called for an unlogged sequence on
a standby server, it will error out with a message like
ERROR: could not open file "base/5/16388": No such file or directory
Since the pg_sequences system view uses pg_sequence_last_value(),
it can error similarly. To fix, modify the function to return NULL
for unlogged sequences on standby servers. Since this bug is
present on all versions since v15, this approach is preferable to
making the ERROR nicer because we need to repair the pg_sequences
view without modifying its definition on released versions. For
consistency, this commit also modifies the function to return NULL
for other sessions' temporary sequences. The pg_sequences view
already appropriately filters out such sequences, so there's no bug
there, but we might as well offer some defense in case someone
invokes this function directly.
Unlogged sequences were first introduced in v15, but temporary
sequences are much older, so while the fix for unlogged sequences
is only back-patched to v15, the temporary sequence portion is
back-patched to all supported versions.
We could also remove the privilege check in the pg_sequences view
definition in v18 if we modify this function to return NULL for
sequences for which the current user lacks privileges, but that is
left as a future exercise for when v18 development begins.
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20240501005730.GA594666%40nathanxps13
Backpatch-through: 12
There are some problems with the new way to handle these constraints
that were detected at the last minute, and require fixes that appear too
invasive to be doing this late in the cycle. Revert this (again) for
now, we'll try again with these problems fixed.
The following commits are reverted:
b0e96f3119 Catalog not-null constraints
9b581c5341 Disallow changing NO INHERIT status of a not-null constraint
d0ec2ddbe0 Fix not-null constraint test
ac22a9545c Move privilege check to the right place
b0f7dd915b Check stack depth in new recursive functions
3af7217942 Update information_schema definition for not-null constraints
c3709100be Fix propagating attnotnull in multiple inheritance
d9f686a72e Fix restore of not-null constraints with inheritance
d72d32f52d Don't try to assign smart names to constraints
0cd711271d Better handle indirect constraint drops
13daa33fa5 Disallow NO INHERIT not-null constraints on partitioned tables
d45597f72f Disallow direct change of NO INHERIT of not-null constraints
21ac38f498 Fix inconsistencies in error messages
Discussion: https://postgr.es/m/202405110940.joxlqcx4dogd@alvherre.pgsql
This commit extends the backend-side infrastructure of injection points
so as it becomes possible to register some input data when attaching a
point. This private data can be registered with the function name and
the library name of the callback when attaching a point, then it is
given as input argument to the callback. This gives the possibility for
modules to pass down custom data at runtime when attaching a point
without managing that internally, in a manner consistent with the
callback entry retrieved from the hash shmem table storing the injection
point data.
InjectionPointAttach() gains two arguments, to be able to define the
private data contents and its size.
A follow-up commit will rely on this infrastructure to close a race
condition with the injection point detach in the module
injection_points.
While on it, this changes InjectionPointDetach() to return a boolean,
returning false if a point cannot be detached. This has been mentioned
by Noah as useful when it comes to implement more complex tests with
concurrent point detach, solid with the automatic detach done for local
points in the test module.
Documentation is adjusted in consequence.
Per discussion with Noah Misch.
Reviewed-by: Noah Misch
Discussion: https://postgr.es/m/20240509031553.47@rfd.leadboat.com
A lot of the examples in this section are quite ancient and no
longer match the system's current behavior. I ran through them
and updated the sample output to match what I get today.
Notably, it seems that the tenk1 table got a few pages smaller back
around v12, so that a lot of the cost estimates for queries on that
table are a little different now. (This also caused some examples
to surprisingly not match others, depending on when they were made.)
One mergejoin-based example no longer produces the same plan at all,
so I had to work around that, including switching to a different
example of using an enable_xxx setting.
I also changed a couple of examples that were relying on nonexistent
tables or indexes. IMO the premise of this section is that the
examples should be more-or-less reproducible against the regression
database, so that these examples were unhelpful as given. It's not
that hard to find a corresponding example with the tables we do have.
Some of the EXPLAIN ANALYZE examples were out of date in that we show
more numbers than we did at the time.
Possibly chapter 68 could use similar review, but I'm out of
energy for today.
User-written triggers can modify or block the effects of SQL update
and delete operations. That includes operations that are executed
to implement foreign keys' referential integrity actions (such as
ON UPDATE SET NULL or ON DELETE CASCADE). Therefore it's possible
for a misdesigned trigger to result in a database state that violates
the foreign key constraint.
While this isn't great, the alternatives seem worse: in particular,
refusing to fire triggers for such updates would break many valuable
use-cases. We could also try to recheck the constraint after the
action, but that'd roughly double the already-high cost of FK
constraint enforcement, for no benefit in normal cases. So we've
always considered that it's on the trigger programmer's head to
avoid breaking RI actions. This was never documented anywhere,
though. Add a para to the Triggers chapter to explain it.
Laurenz Albe, David Johnston, Tom Lane
Discussion: https://postgr.es/m/b81fe38fcc25a81be6e2e5b3fc1ff624130762fa.camel@cybertec.at
Both the pgbench --help output and the reference page have sections
for initialization options, benchmarking options, and common options.
But the --debug option ended up in the wrong place on the reference
page. Fix that by making the documentation match the --help output.
The catalog view pg_stats_ext fails to consider privileges for
expression statistics. The catalog view pg_stats_ext_exprs fails
to consider privileges and row-level security policies. To fix,
restrict the data in these views to table owners or roles that
inherit privileges of the table owner. It may be possible to apply
less restrictive privilege checks in some cases, but that is left
as a future exercise. Furthermore, for pg_stats_ext_exprs, do not
return data for tables with row-level security enabled, as is
already done for pg_stats_ext.
On the back-branches, a fix-CVE-2024-4317.sql script is provided
that will install into the "share" directory. This file can be
used to apply the fix to existing clusters.
Bumps catversion on 'master' branch only.
Reported-by: Lukas Fittl
Reviewed-by: Noah Misch, Tomas Vondra, Tom Lane
Security: CVE-2024-4317
Backpatch-through: 14
Both the initdb --help output and the reference page have a section
for options and a section for less commonly used options. But some
recently added options were sprinkled around inconsistently. Fix that
by making the documentation match the --help output.
We support changing NO INHERIT constraint to INHERIT for constraints in
child relations when adding a constraint to some ancestor relation, and
also during pg_upgrade's schema restore; but other than those special
cases, command ALTER TABLE ADD CONSTRAINT should not be allowed to
change an existing constraint from NO INHERIT to INHERIT, as that would
require to process child relations so that they also acquire an
appropriate constraint, which we may not be in a position to do. (It'd
also be surprising behavior.)
It is conceivable that we want to allow ALTER TABLE SET NOT NULL to make
such a change; but in that case some more code is needed to implement it
correctly, so for now I've made that throw the same error message.
Also, during the prep phase of ALTER TABLE ADD CONSTRAINT, acquire locks
on all descendant tables; otherwise we might operate on child tables on
which no locks are held, particularly in the mode where a primary key
causes not-null constraints to be created on children.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/7d923a66-55f0-3395-cd40-81c142b5448b@gmail.com
Commit 61461a300c accidentally misspelled the PGcancelConn struct
using the PQ prefix (which admittedly is a very easy typo to make).
Reported off-list.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
The documentation said that you need to pick a suitable LC_COLLATE
setting in addition to setting the DETERMINISTIC flag. This would
have been correct if the libc provider supported nondeterministic
collations, but since it doesn't, you actually need to set the LOCALE
option.
Reviewed-by: Kashif Zeeshan <kashi.zeeshan@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/a71023c2-0ae0-45ad-9688-cf3b93d0d65b%40eisentraut.org
This commit makes new partitions created by ALTER TABLE ... SPLIT PARTITION
and ALTER TABLE ... MERGE PARTITIONS commands inherit the paret table access
method.
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/84ada05b-be5c-473e-6d1c-ebe5dd21b190%40gmail.com
Reviewed-by: Pavel Borisov
The createPartitionTable() function is responsible for creating new partitions
for ALTER TABLE ... MERGE PARTITIONS, and ALTER TABLE ... SPLIT PARTITION
commands. It emulates the behaviour of CREATE TABLE ... (LIKE ...), where
new table persistence should be specified by the user. In the table
partitioning persistent of the partition and its parent must match. So, this
commit makes createPartitionTable() copy the persistence of the parent
partition.
Also, this commit makes createPartitionTable() recheck the persistence after
the new table creation. This is needed because persistence might be affected
by pg_temp in search_path.
This commit also changes the signature of createPartitionTable() making it
take the parent's Relation itself instead of the name of the parent relation,
and return the Relation of new partition. That doesn't lead to
complications, because both callers have the parent table open and need to
open the new partition.
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/dbc8b96c-3cf0-d1ee-860d-0e491da20485%40gmail.com
Author: Dmitry Koval
Reviewed-by: Alexander Korotkov, Robert Haas, Justin Pryzby, Pavel Borisov
If an ACL recorded in pg_init_privs mentions a non-pinned role,
that reference must also be noted in pg_shdepend so that we know
that the role can't go away without removing the ACL reference.
Otherwise, DROP ROLE could succeed and leave dangling entries
behind, which is what's causing the recent upgrade-check failures
on buildfarm member copperhead.
This has been wrong since pg_init_privs was introduced, but it's
escaped notice because typical pg_init_privs entries would only
mention the bootstrap superuser (pinned) or at worst the owner
of the extension (who can't go away before the extension does).
We lack even a representation of such a role reference for
pg_shdepend. My first thought for a solution was entries listing
pg_init_privs in classid, but that doesn't work because then there's
noplace to put the granted-on object's classid. Rather than adding
a new column to pg_shdepend, let's add a new deptype code
SHARED_DEPENDENCY_INITACL. Much of the associated boilerplate
code can be cribbed from code for SHARED_DEPENDENCY_ACL.
A lot of the bulk of this patch just stems from the new need to pass
the object's owner ID to recordExtensionInitPriv, so that we can
consult it while updating pg_shdepend. While many callers have that
at hand already, a few places now need to fetch the owner ID of an
arbitrary privilege-bearing object. For that, we assume that there
is a catcache on the relevant catalog's OID column, which is an
assumption already made in ExecGrant_common so it seems okay here.
We do need an entirely new routine RemoveRoleFromInitPriv to perform
cleanup of pg_init_privs ACLs during DROP OWNED BY. It's analogous
to RemoveRoleFromObjectACL, but we can't share logic because that
function operates by building a command parsetree and invoking
existing GRANT/REVOKE infrastructure. There is of course no SQL
command that would update pg_init_privs entries when we're not in
process of creating their extension, so we need a routine that can
do the updates directly.
catversion bump because this changes the expected contents of
pg_shdepend. For the same reason, there's no hope of back-patching
this, even though it fixes a longstanding bug. Fortunately, the
case where it's a problem seems to be near nonexistent in the field.
If it weren't for the buildfarm breakage, I'd have been content to
leave this for v18.
Patch by me; thanks to Daniel Gustafsson for review and discussion.
Discussion: https://postgr.es/m/1745535.1712358659@sss.pgh.pa.us
The paragraph in the docs and the comment applied to
sslnegotiaton=direct, but not sslnegotiation=requiredirect. In
'requiredirect' mode, negotiated SSL is never used. Move the paragraph
in the docs under the description of 'direct' mode, and rephrase it.
Also the comment's reference to reusing a plaintext connection was
bogus. Authentication failure in plaintext mode only happens after
sending the startup packet, so the connection cannot be reused.
Reported-by: Jacob Champion
Discussion: https://www.postgresql.org/message-id/CAOYmi+=sj+1uydS0NR4nYzw-LRWp3Q-s5speBug5UCLSPMbvGA@mail.gmail.com
The --tablespace-mapping option was specified with required_argument
rather than no_argument, which is wrong. Since the actual argument
string passed to getopt_long() included "T:", the single-character
form of the option still worked, but the long form did not. Repair.
The call to getopt_long() erroneously included "P", which doesn't
correspond to any supported option. Remove.
The help message used "do not" in one place and "don't" in another.
Standardize on "do not".
The documentation erroneously stated that the tablespace mappings
would be applied relative to the pathnames in the first backup
specified on the command line, rather than the final one. Fix.
Thanks to Tomas Vondra and Daniel Gustafsson for alerting me to
these mistakes.
Discussion: http://postgr.es/m/CA+TgmoYFznwwaZhHSF1Ze7JeyBv-1yOoSrucKMw37WpF=7RP8g@mail.gmail.com
If not all backups have the same checksum status, but the final backup
has checksums enabled, then the output directory may include pages
with invalid checksums. Document this limitation and explain how to
work around it.
In a future release, we may want to teach pg_combinebackup to
recompute page checksums when required, but as feature freeze has come
and gone, it seems a bit too late to do that for this release.
Patch by me, reviewed by Daniel Gustafsson
Discussion: http://postgr.es/m/CA+TgmoZugzOSmgkx97u3pc0M7U8LycWvugqoyWBv6j15a4hE5g@mail.gmail.com
Allow pg_sync_replication_slots() to error out during promotion of standby.
This makes the behavior of the SQL function consistent with the slot sync
worker. We also ensured that pg_sync_replication_slots() cannot be
executed if sync_replication_slots is enabled and the slotsync worker is
already running to perform the synchronization of slots. Previously, it
would have succeeded in cases when the worker is idle and failed when it
is performing sync which could confuse users.
This patch fixes another issue in the slot sync worker where
SignalHandlerForShutdownRequest() needs to be registered *before* setting
SlotSyncCtx->pid, otherwise, the slotsync worker could miss handling
SIGINT sent by the startup process(ShutDownSlotSync) if it is sent before
worker could register SignalHandlerForShutdownRequest(). To be consistent,
all signal handlers' registration is moved to a prior location before we
set the worker's pid.
Ensure that we clean up synced temp slots at the end of
pg_sync_replication_slots() to avoid such slots being left over after
promotion.
Ensure that ShutDownSlotSync() captures SlotSyncCtx->pid under spinlock to
avoid accessing invalid value as it can be reset by concurrent slot sync
exit due to an error.
Author: Shveta Malik
Reviewed-by: Hou Zhijie, Bertrand Drouvot, Amit Kapila, Masahiko Sawada
Discussion: https://postgr.es/m/CAJpy0uBefXUS_TSz=oxmYKHdg-fhxUT0qfjASW3nmqnzVC3p6A@mail.gmail.com
The paragraph describing the JavaScript string literals allowed in
jsonpath expressions unnecessarily mentions JSON by erroneously
listing \v as allowed by JSON and mentioning the \xNN and \u{N...}
backslash escapes as deviations from JSON when in fact both are
accepted by ECMAScript/JavaScript. Fix this by only referring to
JavaScript.
Author: Erik Wienhold <ewie@ewie.name>
Discussion: https://www.postgresql.org/message-id/flat/1EB17DF9-2636-484B-9DD0-3CAB19C4F5C4@justatheory.com
The paragraph on SSL compression is largely describing events which
took place many years ago, so reword with past tense.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/eac70d46-e61c-4d71-a1e1-78e2bfa19485@eisentraut.org
Do not allow ALTER SUBSCRIPTION ... SET (failover = on|off) in a
transaction block as the changed failover option of the slot can't be
rolled back. For the same reason, we refrain from altering the replication
slot's failover property if the subscription is created with a valid
slot_name and create_slot=false.
Reprted-by: Kuroda Hayato
Author: Hou Zhijie
Reviewed-by: Shveta Malik, Bertrand Drouvot, Kuroda Hayato
Discussion: https://postgr.es/m/OS0PR01MB57165542B09DFA4943830BF294082@OS0PR01MB5716.jpnprd01.prod.outlook.com
The documents were clear that queryid should not be assumed to be stable
between major versions but said nothing about minor versions and left
the reader to guess if that was implied by the mention of the
instability of queryid between major versions.
Here we give minor versions an explicit mention to indicate queryid can
generally be assumed stable between minor versions.
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAApHDvpYGE6h0cD9UO-eHySPynPj1L3J%3DHxT%2BA7Ud8_Yo6AuzA%40mail.gmail.com
Backpatch-through: 12
The optimization for inserts into BRIN indexes added by c1ec02be1d
relies on a cache that needs to be explicitly released after calling
index_insert(). The commit however failed to invoke the cleanup in
validate_index(), which calls index_insert() indirectly through
table_index_validate_scan().
After inspecting index_insert() callers, it seems unique_key_recheck()
is missing the call too.
Fixed by adding the two missing index_insert_cleanup() calls.
The commit does two additional improvements. The aminsertcleanup()
signature is modified to have the index as the first argument, to make
it more like the other AM callbacks. And the aminsertcleanup() callback
is invoked even if the ii_AmCache is NULL, so that it can decide if the
cleanup is necessary.
Author: Alvaro Herrera, Tomas Vondra
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/202401091043.e3nrqiad6gb7@alvherre.pgsql
These operators were removed by 2f70fdb064 in the v14 cycle but they were
accidentally left in the table of build-in operator classes. Backpatch down
to v14 where the operators where removed.
Author: Aleksander Alekseev <aleksander@timescale.com>
Reported-by: Colin Caine <cmcaine@gmail.com>
Discussion: https://postgr.es/m/CADwQTQbbr2UQ_fpbyc+8ay=RwEYgYk=TZxH3+RHDqAQfoG+EWA@mail.gmail.com
Backpatch-through: v14
This updates the link from pg_createsubscriber to initial data sync
to actually link to the subsection in question as opposed to the
main logical replication section.
Author: Pavel Luzanov <p.luzanov@postgrespro.ru>
Discussion: https://postgr.es/m/a4af555a-ac60-4416-877d-0440d29b8763@postgrespro.ru
This fixes various typos, duplicated words, and tiny bits of whitespace
mainly in code comments but also in docs.
Author: Daniel Gustafsson <daniel@yesql.se>
Author: Heikki Linnakangas <hlinnaka@iki.fi>
Author: Alexander Lakhin <exclusion@gmail.com>
Author: David Rowley <dgrowleyml@gmail.com>
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/3F577953-A29E-4722-98AD-2DA9EFF2CBB8@yesql.se
We don't want users to think that pg_combinebackup is trying to check
the validity of individual backups, because it isn't. Adjust the wording
about sanity checks to make it clear that verification of individual
backups is the job of pg_verifybackup, and that the checks performed
by pg_combinebackup are around the relationships between the backups.
Per discussion with David Steele.
Discussion: http://postgr.es/m/e6f930c3-590c-47b9-b094-217bb2a3e22e@pgmasters.net
This addresses some post-commit review comments for commits 6185c973,
de3600452, and 9425c596a0, with the following changes:
* Fix JSON_TABLE() syntax documentation to use the term
"path_expression" for JSON path expressions instead of
"json_path_specification" to be consistent with the other SQL/JSON
functions.
* Fix a typo in the example code in JSON_TABLE() documentation.
* Rewrite some newly added comments in jsonpath.h.
* In JsonPathQuery(), add missing cast to int before printing an enum
value.
Reported-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxG_e0QLCgaELrr2ZNz7AxPeGCNKAORe3fHtFCQLsH4J4Q@mail.gmail.com
The code associated with EXEC SQL DEFINE was unreadable and full of
bugs, notably:
* It'd attempt to free a non-malloced string if the ecpg program
tries to redefine a macro that was defined on the command line.
* Possible memory stomp if user writes "-D=foo".
* Undef'ing or redefining a macro defined on the command line would
change the state visible to the next file, when multiple files are
specified on the command line. (While possibly that could have been
an intentional choice, the code clearly intends to revert to the
original macro state; it's just failing to consider this interaction.)
* Missing "break" in defining a new macro meant that redefinition
of an existing name would cause an extra entry to be added to the
definition list. While not immediately harmful, a subsequent undef
would result in the prior entry becoming visible again.
* The interactions with input buffering are subtle and were entirely
undocumented.
It's not that surprising that we hadn't noticed these bugs,
because there was no test coverage at all of either the -D
command line switch or multiple input files. This patch adds
such coverage (in a rather hacky way I guess).
In addition to the code bugs, the user documentation was confused
about whether the -D switch defines a C macro or an ecpg one, and
it failed to mention that you can write "-Dsymbol=value".
These problems are old, so back-patch to all supported branches.
Discussion: https://postgr.es/m/998011.1713217712@sss.pgh.pa.us
Previously, we had consecutive, very short chapters called "Generic
WAL" and "Custom WAL Resource Managers," explaining different approaches
to the same problem. Merge them into a single chapter. Explain most
of the differences between the approaches in the chapter's
introductory text, rather than in the individual sections.
Discussion: http://postgr.es/m/46ac50c1-6b2a-404f-a683-b67af6ab56e9@eisentraut.org
The documentation for SET ROLE states that superusers who switch to
a non-superuser role lose their superuser privileges. While this
is true for most commands, there are exceptions such as SET ROLE
and SET SESSION AUTHORIZATION, which continue to use the current
session user and the authenticated user, respectively.
Furthermore, the description of this command already describes its
effect, so it is arguably unnecessary to include this special case.
This commit removes the note about the superuser case and adds a
sentence about the aforementioned exceptions to the description.
Co-authored-by: Yurii Rashkovskii
Reviewed-by: Shubham Khanna, Robert Haas, Michael Paquier
Discussion: https://postgr.es/m/CA%2BRLCQysHtME0znk2KUMJN343ksboSRQSU-hCnOjesX6VK300Q%40mail.gmail.com
This addresses a few problems with commit e5da0fe3c2 ("Catalog domain
not-null constraints").
In CREATE DOMAIN, a NOT NULL constraint looks like
CREATE DOMAIN d1 AS int [ CONSTRAINT conname ] NOT NULL
(Before e5da0fe3c2, the constraint name was accepted but ignored.)
But in ALTER DOMAIN, a NOT NULL constraint looks like
ALTER DOMAIN d1 ADD [ CONSTRAINT conname ] NOT NULL VALUE
where VALUE is where for a table constraint the column name would be.
(This works as of e5da0fe3c2. Before e5da0fe3c2, this syntax
resulted in an internal error.)
But for domains, this latter syntax is confusing and needlessly
inconsistent between CREATE and ALTER. So this changes it to just
ALTER DOMAIN d1 ADD [ CONSTRAINT conname ] NOT NULL
(None of these syntaxes are per SQL standard; we are just living with
the bits of inconsistency that have built up over time.)
In passing, this also changes the psql \dD output to not show not-null
constraints in the column "Check", since it's already shown in the
column "Nullable". This has also been off since e5da0fe3c2.
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/9ec24d7b-633d-463a-84c6-7acff769c9e8%40eisentraut.org
In the libpq encryption negotiation tests, don't run the GSSAPI tests
unless PG_TEST_EXTRA='kerberos' is also set. That makes it possible to
still run most of the tests when GSSAPI support is compiled in, but
there's no MIT Kerberos installation.
The tools.ietf.org site has been decommissioned and replaced by a
number of sites serving various purposes. Links to RFCs and BCPs
are now 301 redirected to their new respective IETF sites. Since
this serves no purpose and only adds network overhead, update our
links to the new locations.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/3C1CEA99-FCED-447D-9858-5A579B4C6687@yesql.se
Backpatch-through: v12
A NESTED path allows to extract data from nested levels of JSON
objects given by the parent path expression, which are projected as
columns specified using a nested COLUMNS clause, just like the parent
COLUMNS clause. Rows comprised from a NESTED columns are "joined"
to the row comprised from the parent columns. If a particular NESTED
path evaluates to 0 rows, then the nested COLUMNS will emit NULLs,
making it an OUTER join.
NESTED columns themselves may include NESTED paths to allow
extracting data from arbitrary nesting levels, which are likewise
joined against the rows at the parent level.
Multiple NESTED paths at a given level are called "sibling" paths
and their rows are combined by UNIONing them, that is, after being
joined against the parent row as described above.
Author: Nikita Glukhov <n.gluhov@postgrespro.ru>
Author: Teodor Sigaev <teodor@sigaev.ru>
Author: Oleg Bartunov <obartunov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
Author: Andrew Dunstan <andrew@dunslane.net>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewers have included (in no particular order):
Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup,
Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson,
Justin Pryzby, Álvaro Herrera, Jian He
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de
Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
When testing buffer pool logic, it is useful to be able to evict
arbitrary blocks. This function can be used in SQL queries over the
pg_buffercache view to set up a wide range of buffer pool states. Of
course, buffer mappings might change concurrently so you might evict a
block other than the one you had in mind, and another session might
bring it back in at any time. That's OK for the intended purpose of
setting up developer testing scenarios, and more complicated interlocking
schemes to give stronger guararantees about that would likely be less
flexible for actual testing work anyway. Superuser-only.
Author: Palak Chaturvedi <chaturvedipalak1911@gmail.com>
Author: Thomas Munro <thomas.munro@gmail.com> (docs, small tweaks)
Reviewed-by: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Cary Huang <cary.huang@highgo.ca>
Reviewed-by: Cédric Villemain <cedric.villemain+pgsql@abcsql.com>
Reviewed-by: Jim Nasby <jim.nasby@gmail.com>
Reviewed-by: Maxim Orlov <orlovmg@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CALfch19pW48ZwWzUoRSpsaV9hqt0UPyaBPC4bOZ4W+c7FF566A@mail.gmail.com
libpq now always tries to send ALPN. With the traditional negotiated
SSL connections, the server accepts the ALPN, and refuses the
connection if it's not what we expect, but connecting without ALPN is
still OK. With the new direct SSL connections, ALPN is mandatory.
NOTE: This uses "TBD-pgsql" as the protocol ID. We must register a
proper one with IANA before the release!
Author: Greg Stark, Heikki Linnakangas
Reviewed-by: Matthias van de Meent, Jacob Champion
By skipping SSLRequest, you can eliminate one round-trip when
establishing a TLS connection. It is also more friendly to generic TLS
proxies that don't understand the PostgreSQL protocol.
This is disabled by default in libpq, because the direct TLS handshake
will fail with old server versions. It can be enabled with the
sslnegotation=direct option. It will still fall back to the negotiated
TLS handshake if the server rejects the direct attempt, either because
it is an older version or the server doesn't support TLS at all, but
the fallback can be disabled with the sslnegotiation=requiredirect
option.
Author: Greg Stark, Heikki Linnakangas
Reviewed-by: Matthias van de Meent, Jacob Champion
Replace (expr op C1) OR (expr op C2) ... with expr op ANY(ARRAY[C1, C2, ...])
on the preliminary stage of optimization when we are still working with the
expression tree.
Here Cn is a n-th constant expression, 'expr' is non-constant expression, 'op'
is an operator which returns boolean result and has a commuter (for the case
of reverse order of constant and non-constant parts of the expression,
like 'Cn op expr').
Sometimes it can lead to not optimal plan. This is why there is a
or_to_any_transform_limit GUC. It specifies a threshold value of length of
arguments in an OR expression that triggers the OR-to-ANY transformation.
Generally, more groupable OR arguments mean that transformation will be more
likely to win than to lose.
Discussion: https://postgr.es/m/567ED6CA.2040504%40sigaev.ru
Author: Alena Rybakina <lena.ribackina@yandex.ru>
Author: Andrey Lepikhov <a.lepikhov@postgrespro.ru>
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
What the documentation calls an exclude_element is an index_elem
according to gram.y, and it allows all the same options that
a CREATE INDEX column specification does. The COLLATE patch
neglected to update the CREATE/ALTER TABLE docs about that,
and later the opclass-parameters patch made the same oversight.
Add those options to the syntax synopses, and polish the
associated text a bit.
Back-patch to v13 where opclass parameters came in. We could
update v12 with just the COLLATE omission, but it doesn't quite
seem worth the trouble at this point.
Shihao Zhong, reviewed by Daniel Vérité, Shubham Khanna and myself
Discussion: https://postgr.es/m/CAGRkXqShbVyB8E3gapfdtuwiWTiK=Q67Qb9qwxu=+-w0w46EBA@mail.gmail.com
This patch generalizes libpq's existing single-row mode to allow
individual partial-result PGresults to contain up to N rows, rather
than always one row. This reduces malloc overhead compared to plain
single-row mode, and it is very useful for psql's FETCH_COUNT feature,
since otherwise we'd have to add code (and cycles) to either merge
single-row PGresults into a bigger one or teach psql's
results-printing logic to accept arrays of PGresults.
To avoid API breakage, PQsetSingleRowMode() remains the same, and we
add a new function PQsetChunkedRowsMode() to invoke the more general
case. Also, PGresults obtained the old way continue to carry the
PGRES_SINGLE_TUPLE status code, while if PQsetChunkedRowsMode() is
used then their status code is PGRES_TUPLES_CHUNK. The underlying
logic is the same either way, though.
Daniel Vérité, reviewed by Laurenz Albe and myself (and whacked
around a bit by me, so any remaining bugs are my fault)
Discussion: https://postgr.es/m/CAKZiRmxsVTkO928CM+-ADvsMyePmU3L9DQCa9NwqjvLPcEe5QA@mail.gmail.com
This new DDL command splits a single partition into several parititions.
Just like ALTER TABLE ... MERGE PARTITIONS ... command, new patitions are
created using createPartitionTable() function with parent partition as the
template.
This commit comprises quite naive implementation which works in single process
and holds the ACCESS EXCLUSIVE LOCK on the parent table during all the
operations including the tuple routing. This is why this new DDL command
can't be recommended for large partitioned tables under a high load. However,
this implementation come in handy in certain cases even as is.
Also, it could be used as a foundation for future implementations with lesser
locking and possibly parallel.
Discussion: https://postgr.es/m/c73a1746-0cd0-6bdd-6b23-3ae0b7c0c582%40postgrespro.ru
Author: Dmitry Koval
Reviewed-by: Matthias van de Meent, Laurenz Albe, Zhihong Yu, Justin Pryzby
Reviewed-by: Alvaro Herrera, Robert Haas, Stephane Tachoires
This new DDL command merges several partitions into the one partition of the
target table. The target partition is created using new
createPartitionTable() function with parent partition as the template.
This commit comprises quite naive implementation which works in single process
and holds the ACCESS EXCLUSIVE LOCK on the parent table during all the
operations including the tuple routing. This is why this new DDL command
can't be recommended for large partitioned tables under a high load. However,
this implementation come in handy in certain cases even as is.
Also, it could be used as a foundation for future implementations with lesser
locking and possibly parallel.
Discussion: https://postgr.es/m/c73a1746-0cd0-6bdd-6b23-3ae0b7c0c582%40postgrespro.ru
Author: Dmitry Koval
Reviewed-by: Matthias van de Meent, Laurenz Albe, Zhihong Yu, Justin Pryzby
Reviewed-by: Alvaro Herrera, Robert Haas, Stephane Tachoires
Commit 9e8da0f7 taught nbtree to handle ScalarArrayOpExpr quals
natively. This works by pushing down the full context (the array keys)
to the nbtree index AM, enabling it to execute multiple primitive index
scans that the planner treats as one continuous index scan/index path.
This earlier enhancement enabled nbtree ScalarArrayOp index-only scans.
It also allowed scans with ScalarArrayOp quals to return ordered results
(with some notable restrictions, described further down).
Take this general approach a lot further: teach nbtree SAOP index scans
to decide how to execute ScalarArrayOp scans (when and where to start
the next primitive index scan) based on physical index characteristics.
This can be far more efficient. All SAOP scans will now reliably avoid
duplicative leaf page accesses (just like any other nbtree index scan).
SAOP scans whose array keys are naturally clustered together now require
far fewer index descents, since we'll reliably avoid starting a new
primitive scan just to get to a later offset from the same leaf page.
The scan's arrays now advance using binary searches for the array
element that best matches the next tuple's attribute value. Required
scan key arrays (i.e. arrays from scan keys that can terminate the scan)
ratchet forward in lockstep with the index scan. Non-required arrays
(i.e. arrays from scan keys that can only exclude non-matching tuples)
"advance" without the process ever rolling over to a higher-order array.
Naturally, only required SAOP scan keys trigger skipping over leaf pages
(non-required arrays cannot safely end or start primitive index scans).
Consequently, even index scans of a composite index with a high-order
inequality scan key (which we'll mark required) and a low-order SAOP
scan key (which we won't mark required) now avoid repeating leaf page
accesses -- that benefit isn't limited to simpler equality-only cases.
In general, all nbtree index scans now output tuples as if they were one
continuous index scan -- even scans that mix a high-order inequality
with lower-order SAOP equalities reliably output tuples in index order.
This allows us to remove a couple of special cases that were applied
when building index paths with SAOP clauses during planning.
Bugfix commit 807a40c5 taught the planner to avoid generating unsafe
path keys: path keys on a multicolumn index path, with a SAOP clause on
any attribute beyond the first/most significant attribute. These cases
are now all safe, so we go back to generating path keys without regard
for the presence of SAOP clauses (just like with any other clause type).
Affected queries can now exploit scan output order in all the usual ways
(e.g., certain "ORDER BY ... LIMIT n" queries can now terminate early).
Also undo changes from follow-up bugfix commit a4523c5a, which taught
the planner to produce alternative index paths, with path keys, but
without low-order SAOP index quals (filter quals were used instead).
We'll no longer generate these alternative paths, since they can no
longer offer any meaningful advantages over standard index qual paths.
Affected queries thereby avoid all of the disadvantages that come from
using filter quals within index scan nodes. They can avoid extra heap
page accesses from using filter quals to exclude non-matching tuples
(index quals will never have that problem). They can also skip over
irrelevant sections of the index in more cases (though only when nbtree
determines that starting another primitive scan actually makes sense).
There is a theoretical risk that removing restrictions on SAOP index
paths from the planner will break compatibility with amcanorder-based
index AMs maintained as extensions. Such an index AM could have the
same limitations around ordered SAOP scans as nbtree had up until now.
Adding a pro forma incompatibility item about the issue to the Postgres
17 release notes seems like a good idea.
Author: Peter Geoghegan <pg@bowt.ie>
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reviewed-By: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reviewed-By: Tomas Vondra <tomas.vondra@enterprisedb.com>
Discussion: https://postgr.es/m/CAH2-Wz=ksvN_sjcnD1+Bt-WtifRA5ok48aDYnq3pkKhxgMQpcw@mail.gmail.com
The BAS_VACUUM ring size has been 256kB since commit d526575f introduced
the mechanism 17 years ago. Commit 1cbbee03 recently made it
configurable but retained the traditional default. The correct default
size has been debated for years, but 256kB is certainly very small.
VACUUM soon needs to write back data it dirtied only 32 blocks ago,
which usually requires flushing the WAL. New experiments in prefetching
pages for VACUUM exacerbated the problem by crashing into dirty data
even sooner. Let's make the default 2MB. That's 1.6% of the default
toy buffer pool size, and 0.2% of 1GB, which would be a considered a
small shared_buffers setting for a real system these days. Users are
still free to set the GUC to a different value.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20240403221257.md4gfki3z75cdyf6%40awork3.anarazel.de
Discussion: https://postgr.es/m/CA%2BhUKGLY4Q4ZY4f1rvnFtv6%2BPkjNf8MejdPkcju3Qii9DYqqcQ%40mail.gmail.com
Adds --clone/--copy-file-range options to pg_combinebackup, to allow
copying files using file cloning or copy_file_range(). These methods may
be faster than the standard block-by-block copy, but the main advantage
is that they enable various features provided by CoW filesystems.
This commit only uses these copy methods for files that did not change
and can be copied as a whole from a single backup.
These new copy methods may not be available on all platforms, in which
case the command throws an error (immediately, even if no files would be
copied as a whole). This early failure seems better than failing later
when trying to copy the first file, after performing a lot of work on
earlier files.
If the requested copy method is available, but a checksum needs to be
recalculated (e.g. because of a different checksum type), the file is
still copied using the requested method, but it is also read for the
checksum calculation. Depending on the filesystem this may be more
expensive than just performing the simple copy, but it does enable the
CoW benefits.
Initial patch by Jakub Wartak, various reworks and improvements by me.
Author: Tomas Vondra, Jakub Wartak
Reviewed-by: Thomas Munro, Jakub Wartak, Robert Haas
Discussion: https://postgr.es/m/3024283a-7491-4240-80d0-421575f6bb23%40enterprisedb.com
The documentation index is getting very long, which makes it hard
to find things. Since these chapters are all very similar in structure
and content, merging them is a natural way of reducing the size of
the toplevel index.
Rather than actually combining all of the SGML into a single file,
keep one file per <sect1>, and add a glue file that includes all
of them.
Discussion: http://postgr.es/m/CA+Tgmob7_uoYuS2=rVwpVXaRwP-UXz+++saYTC-BCZ42QzSNKQ@mail.gmail.com
This commit does two things:
1) Maintains inactive_since for sync slots whenever the slot is released
just like any other regular slot.
2) Ensures the value is set to the current timestamp during the promotion
of standby to help correctly interpret the time after promotion. We don't
want the slots to appear inactive for a long time after promotion if they
haven't been synchronized recently. This would also avoid the invalidation
of such slots immediately after promotion if tomorrow we have a feature
that invalidates slots based on their inactivity time. Whoever acquires
the slot i.e. makes the slot active will reset it to NULL.
Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Amit Kapila, Shveta Malik, Masahiko Sawada
Discussion: https://postgr.es/m/CAA4eK1KrPGwfZV9LYGidjxHeW+rxJ=E2ThjXvwRGLO=iLNuo=Q@mail.gmail.com
Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com
Discussion: https://postgr.es/m/CA+Tgmob_Ta-t2ty8QrKHBGnNLrf4ZYcwhGHGFsuUoFrAEDw4sA@mail.gmail.com
JSON_TABLE() allows JSON data to be converted into a relational view
and thus used, for example, in a FROM clause, like other tabular
data. Data to show in the view is selected from a source JSON object
using a JSON path expression to get a sequence of JSON objects that's
called a "row pattern", which becomes the source to compute the
SQL/JSON values that populate the view's output columns. Column
values themselves are computed using JSON path expressions applied to
each of the JSON objects comprising the "row pattern", for which the
SQL/JSON query functions added in 6185c9737c are used.
To implement JSON_TABLE() as a table function, this augments the
TableFunc and TableFuncScanState nodes that are currently used to
support XMLTABLE() with some JSON_TABLE()-specific fields.
Note that the JSON_TABLE() spec includes NESTED COLUMNS and PLAN
clauses, which are required to provide more flexibility to extract
data out of nested JSON objects, but they are not implemented here
to keep this commit of manageable size.
Author: Nikita Glukhov <n.gluhov@postgrespro.ru>
Author: Teodor Sigaev <teodor@sigaev.ru>
Author: Oleg Bartunov <obartunov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
Author: Andrew Dunstan <andrew@dunslane.net>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewers have included (in no particular order):
Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup,
Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson,
Justin Pryzby, Álvaro Herrera, Jian He
Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru
Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de
Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
Discussion: https://postgr.es/m/CA+HiwqE4XTdfb1nW=Ojoy_tQSRhYt-q_kb6i5d4xcKyrLC1Nbg@mail.gmail.com
EXPLAIN (ANALYZE, SERIALIZE) allows collection of statistics about
the volume of data emitted by a query, as well as the time taken
to convert the data to the on-the-wire format. Previously there
was no way to investigate this without actually sending the data
to the client, in which case network transmission costs might
swamp what you wanted to see. In particular this feature allows
investigating the costs of de-TOASTing compressed or out-of-line
data during formatting.
Stepan Rutz and Matthias van de Meent,
reviewed by Tomas Vondra and myself
Discussion: https://postgr.es/m/ca0adb0e-fa4e-c37e-1cd7-91170b18cae1@gmx.de
Peter Eisentraut
Bruce Momjian
Nathan Bossart
Alvaro Herrera
Michael Paquier
Heikki Linnakangas
Tom Lane
Alexander Korotkov
David Rowley
Daniel Gustafsson
Robert Haas
Amit Kapila
Tomas Vondra
Amit Langote
Masahiko Sawada
Noah Misch
Thomas Munro
Peter Geoghegan