find_computable_ec_member() had the wrong mental model of what
its primary caller prepare_sort_from_pathkeys() would do with
the selected EquivalenceClass member expression. We will not
compute the EC expression in a plan node atop the one returning
the passed-in targetlist; rather, the EC expression will be
computed as an additional column of that targetlist. So any
Var or quasi-Var used in the given tlist is also available to the
EC expression. In simple cases this makes no difference because
the given tlist is just a list of Vars or quasi-Vars --- but if
we are considering an appendrel member produced by flattening
a UNION ALL, the tlist may contain expressions, resulting in
failure to match and a "could not find pathkey item to sort"
error.
To fix, we can flatten both the tlist and the EC members with
pull_var_clause(), and then just check for subset-ness, so
that the code is actually shorter than before.
While this bug is quite old, the present patch only works back to
v13. We could possibly make it work in v12 by back-patching parts
of 375398244. On the whole though I don't like the risk/reward
ratio of that idea. v12's final release is next month, meaning
there would be no chance to correct matters if the patch causes a
regression. Since this failure has escaped notice for 14 years,
it's likely nobody will hit it in the field with v12.
Per bug #18652 from Alexander Lakhin.
Andrei Lepikhov and Tom Lane
Discussion: https://postgr.es/m/18652-deaa782ebcca85d1@postgresql.org
A missed check for the builtin collation provider could result in
falling through to call isalpha().
This does not appear to have practical consequences because it only
happens for characters in the ASCII range. Regardless, the builtin
provider should not be calling libc functions, so backpatch.
Discussion: https://postgr.es/m/1bd5a0a5192f82c22ee7527e825b18ab0028b2c7.camel@j-davis.com
Backpatch-through: 17
PostgreSQL has for a long time mixed two BIO implementations, which can
lead to subtle bugs and inconsistencies. This cleans up our BIO by just
just setting up the methods we need. This patch does not introduce any
functionality changes.
The following methods are no longer defined due to not being needed:
- gets: Not used by libssl
- puts: Not used by libssl
- create: Sets up state not used by libpq
- destroy: Not used since libpq use BIO_NOCLOSE, if it was used it close
the socket from underneath libpq
- callback_ctrl: Not implemented by sockets
The following methods are defined for our BIO:
- read: Used for reading arbitrary length data from the BIO. No change
in functionality from the previous implementation.
- write: Used for writing arbitrary length data to the BIO. No change
in functionality from the previous implementation.
- ctrl: Used for processing ctrl messages in the BIO (similar to ioctl).
The only ctrl message which matters is BIO_CTRL_FLUSH used for
writing out buffered data (or signal EOF and that no more data
will be written). BIO_CTRL_FLUSH is mandatory to implement and
is implemented as a no-op since there is no intermediate buffer
to flush.
BIO_CTRL_EOF is the out-of-band method for signalling EOF to
read_ex based BIO's. Our BIO is not read_ex based but someone
could accidentally call BIO_CTRL_EOF on us so implement mainly
for completeness sake.
As the implementation is no longer related to BIO_s_socket or calling
SSL_set_fd, methods have been renamed to reference the PGconn and Port
types instead.
This also reverts back to using BIO_set_data, with our fallback, as a small
optimization as BIO_set_app_data require the ex_data mechanism in OpenSSL.
Author: David Benjamin <davidben@google.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAF8qwaCZ97AZWXtg_y359SpOHe+HdJ+p0poLCpJYSUxL-8Eo8A@mail.gmail.com
This function returns the name, size, and last modification time of
each regular file in pg_wal/summaries. This allows administrators
to grant privileges to view the contents of this directory without
granting privileges on pg_ls_dir(), which allows listing the
contents of many other directories. This commit also gives the
pg_monitor predefined role EXECUTE privileges on the new
pg_ls_summariesdir() function.
Bumps catversion.
Author: Yushi Ogiwara
Reviewed-by: Michael Paquier, Fujii Masao
Discussion: https://postgr.es/m/a0a3af15a9b9daa107739eb45aa9a9bc%40oss.nttdata.com
Both functions advance the transaction ID, which modifies the system
state. Thus, they should be marked as VOLATILE.
Additionally, they call the AssignTransactionId function, which cannot
be invoked in parallel mode, so they should be marked as PARALLEL
UNSAFE.
Author: Yushi Ogiwara <btogiwarayuushi@oss.nttdata.com>
Discussion: https://www.postgresql.org/message-id/18f01e4fd46448f88c7a1363050a9955@oss.nttdata.com
Previously, per-script statistics were never output when all
transactions failed due to serialization or deadlock errors. However,
it is reasonable to report such information if there are ones even
when there are no successful transaction since these failed
transactions are now objects to be reported.
Meanwhile, if the total number of successful, skipped, and failed
transactions is zero, we don't have to report the number of failed
transactions as similar to the number of skipped transactions, which
avoids to print "NaN%" in lines on failed transaction reports.
Also, the number of transactions in per-script results now includes
skipped and failed transactions. It prevents to print "total of NaN%"
when any transactions are not successfully processed. The number of
transactions actually processed per-script and TPS based on it are now
output explicitly in a separate line.
Author: Yugo Nagata
Reviewed-by: Tatsuo Ishii
Discussion: https://postgr.es/m/20240921003544.2436ef8da9c5c8cb963c651b%40sraoss.co.jp
c01743aa4 added EXPLAIN output to display the plan node's disabled_node
count whenever that count is above 0. Seemingly, there weren't many
people who liked that output as each parent of a disabled node would
also have a "Disabled Nodes" output due to the way disabled_nodes is
accumulated towards the root plan node. It was often hard and sometimes
impossible to figure out which nodes were disabled from looking at
EXPLAIN. You might think it would be possible to manually add up the
numbers from the "Disabled Nodes" output of a given node's children to
figure out if that node has a higher disabled_nodes count than its
children, but that wouldn't have worked for Append and Merge Append nodes
if some disabled child nodes were run-time pruned during init plan. Those
children are not displayed in EXPLAIN.
Here we attempt to improve this output by only showing "Disabled: true"
against only the nodes which are explicitly disabled themselves. That
seems to be the output that's desired by the most people who voiced
their opinion. This is done by summing up the disabled_nodes of the
given node's children and checking if that number is less than the
disabled_nodes of the current node.
This commit also fixes a bug in make_sort() which was neglecting to set
the Sort's disabled_nodes field. This should have copied what was done
in cost_sort(), but it hadn't been updated. With the new output, the
choice to not maintain that field properly was clearly wrong as the
disabled-ness of the node was attributed to the Sort's parent instead.
Reviewed-by: Laurenz Albe, Alena Rybakina
Discussion: https://postgr.es/m/9e4ad616bebb103ec2084bf6f724cfc739e7fabb.camel@cybertec.at
Use $ARGV[0], that is the specified input file name, in #line
directives generated by gen_tabcomplete.pl. This makes code
coverage reports work properly in the meson build system (where
the input file name will be a relative path).
Also fix up brain fade in the meson build rule for tab-complete.c:
we only need to write the input file name once not twice.
Jacob Champion (some cosmetic adjustments by me)
Discussion: https://postgr.es/m/CAOYmi+=+oWAoi8pqnH0MJQqsSn4ddzqDhqRQJvyiN2aJSWvw2w@mail.gmail.com
Fix oversight in bd1276a3c: the "words_after_create" stanza in
psql_completion() requires previous_words_count > 0, since it uses
prev_wd. This condition was formerly assured by the if-else chain
above it, but no more. If there were no previous words then we'd
dereference an uninitialized pointer, possibly causing a segfault.
Report and patch by Anthonin Bonnefoy.
Discussion: https://postgr.es/m/CAO6_XqrSRE7c_i+D7Hm07K3+6S0jTAmMr60RY41XzaA29Ae5uA@mail.gmail.com
Commit 90189eefc1 narrowed pg_attribute.attinhcount and
pg_constraint.coninhcount from 32 to 16 bits, but kept other related
structs with 32-bit wide fields: ColumnDef and CookedConstraint contain
an int 'inhcount' field which is itself checked for overflow on
increments, but there's no check that the values aren't above INT16_MAX
before assigning to the catalog columns. This means that a creative
user can get a inconsistent table definition and override some
protections.
Fix it by changing those other structs to also use int16.
Also, modernize style by using pg_add_s16_overflow for overflow testing
instead of checking for negative values.
We also have Constraint.inhcount, which is here removed completely.
This was added by commit b0e96f3119 and not removed by its revert at
6f8bb7c1e9. It is not needed by the upcoming not-null constraints
patch.
This is mostly academic, so we agreed not to backpatch to avoid ABI
problems.
Bump catversion because of the changes to parse nodes.
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Co-authored-by: 何建 (jian he) <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202410081611.up4iyofb5ie7@alvherre.pgsql
Previously, the descriptions of pg_stat_get_checkpointer_num_requested(),
pg_stat_get_checkpointer_restartpoints_requested(),
and pg_stat_get_checkpointer_restartpoints_performed() in pg_proc.dat
referred to "backend". This was misleading because these functions report
the number of checkpoints or restartpoints requested or performed
by other than backends as well.
This commit removes "backend" from these descriptions to avoid confusion.
Bump catalog version.
Idea from Anton A. Melnikov
Author: Fujii Masao
Reviewed-by: Anton A. Melnikov
Discussion: https://postgr.es/m/8e5f353f-8b31-4a8e-9cfa-c037f22b4aee@postgrespro.ru
Commit 9391f7152 added a "PlannerInfo *root" parameter to
estimate_array_length, but failed to consider the possibility that
NULL would be passed for that, leading to a null pointer dereference.
We could rectify the particular case shown in the bug report by fixing
simplify_function/inline_function to pass through the root pointer.
However, as long as eval_const_expressions is documented to accept
NULL for root, similar hazards would remain. For now, let's just do
the narrow fix of hardening estimate_array_length to not crash.
Its behavior with NULL root will be the same as it was before
9391f7152, so this is not too awful.
Per report from Fredrik Widlert (via Paul Ramsey). Back-patch to v17
where 9391f7152 came in.
Discussion: https://postgr.es/m/518339E7-173E-45EC-A0FF-9A4A62AA4F40@cleverelephant.ca
The name extracted from the record of the GUC tables is applied to more
internal places of guc.c. This change has the advantage to simplify
parse_and_validate_value(), where the "name" was only used in elog
messages, while it was required to match with the name from the GUC
record.
pg_parameter_aclcheck() now passes the name of the GUC from its record
in two places rather than the caller's argument. The value given to
this function goes through convert_GUC_name_for_parameter_acl() that
does a simple ASCII downcasing.
Few GUCs mix character casing in core; one test is added for one of
these code paths with "IntervalStyle".
Author: Peter Smith, Michael Paquier
Discussion: https://postgr.es/m/ZwNh4vkc2NHJHnND@paquier.xyz
In some cases, we may want to transfer a HAVING clause into WHERE in
hopes of eliminating tuples before aggregation instead of after.
Previously, we couldn't do this if there were any nonempty grouping
sets, because we didn't have a way to tell if the HAVING clause
referenced any columns that were nullable by the grouping sets, and
moving such a clause into WHERE could potentially change the results.
Now, with expressions marked nullable by grouping sets with the RT
index of the RTE_GROUP RTE, it is much easier to identify those
clauses that reference any nullable-by-grouping-sets columns: we just
need to check if the RT index of the RTE_GROUP RTE is present in the
clause. For other HAVING clauses, they can be safely pushed down.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-NpzPgtKU=hgnvyn+J-GanxQCjrUi7piNzZ=upiCV=2Q@mail.gmail.com
For a mergejoin, if the given outer path or inner path is not already
well enough ordered, we need to do an explicit sort. Currently, we
only consider explicit full sort and do not account for incremental
sort.
In this patch, for the outer path of a mergejoin, we choose to use
explicit incremental sort if it is enabled and there are presorted
keys. For the inner path, though, we cannot use incremental sort
because it does not support mark/restore at present.
The rationale is based on the assumption that incremental sort is
always faster than full sort when there are presorted keys, a premise
that has been applied in various parts of the code. In addition, the
current cost model tends to favor incremental sort as being cheaper
than full sort in the presence of presorted keys, making it reasonable
not to consider full sort in such cases.
It could be argued that what if a mergejoin with an incremental sort
as the outer path is selected as the inner path of another mergejoin.
However, this should not be a problem, because mergejoin itself does
not support mark/restore either, and we will add a Material node on
top of it anyway in this case (see final_cost_mergejoin).
There is one ensuing plan change in the regression tests, and we have
to modify that test case to ensure that it continues to test what it
is intended to.
No backpatch as this could result in plan changes.
Author: Richard Guo
Reviewed-by: David Rowley, Tomas Vondra
Discussion: https://postgr.es/m/CAMbWs49x425QrX7h=Ux05WEnt8GS757H-jOP3_xsX5t1FoUsZw@mail.gmail.com
Commit 149ac7d455 which re-implemented pgindent in Perl explicitly
imported the devnull function from File::Spec, but the module does
not export anything. In recent versions of Perl calling a missing
import function cause a warning, which combined with warnings being
fatal cause pgindent to error out.
Backpatch to all supported versions.
Author: Erik Wienhold <ewie@ewie.name>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discusson: https://postgr.es/m/2372cd74-11b0-46f9-b28e-8f9627215d19@ewie.name
Backpatch-through: v12
The view pg_stat_statements gains two columns:
- parallel_workers_to_launch, the number of parallel workers planned to
be launched.
- parallel_workers_launched, the number of parallel workers actually
launched.
The ratio of both columns offers hints that parallel workers are lacking
on a per-statement basis, requiring some tuning, in coordination with
"calls", the number of times a query is executed.
As of now, these numbers are tracked within Gather and GatherMerge
nodes. They could be extended to utilities that make use of parallel
workers (parallel btree and brin, VACUUM).
The module is bumped to 1.12.
Author: Guillaume Lelarge
Discussion: https://postgr.es/m/CAECtzeWtTGOK0UgKXdDGpfTVSa5bd_VbUt6K6xn8P7X+_dZqKw@mail.gmail.com
These fields can be set by executor nodes to record how many parallel
workers were planned to be launched and how many of them have been
actually launched within the number initially planned. This data is
able to give an approximation of the parallel worker draught a system
is facing, making easier the tuning of related configuration parameters.
These fields will be used by some follow-up patches to populate other
parts of the system with their data.
Author: Guillaume Lelarge, Benoit Lobréau
Discussion: https://postgr.es/m/783bc7f7-659a-42fa-99dd-ee0565644e25@dalibo.com
Discussion: https://postgr.es/m/CAECtzeWtTGOK0UgKXdDGpfTVSa5bd_VbUt6K6xn8P7X+_dZqKw@mail.gmail.com
Remove unnecessary chatter about "checking if IO::Socket::UNIX works";
our tests should never print anything on stderr unless there's a
problem.
Add .gitignore entry for temporary directory now being left behind
in src/test/postmaster.
AIO will need a resource owner to do IO. Right now we create a resowner
on-demand during basebackup, and we could do the same for AIO. But it seems
easier to just always create an aux process resowner.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
With real AIO it doesn't make sense to cross segment boundaries with one
IO. Add smgrmaxcombine() to allow upper layers to query which buffers can be
merged.
We could continue to cross segment boundaries when not using AIO, but it
doesn't really make sense, because md.c will never be able to perform the read
across the segment boundary in one system call. Which means we'll mark more
buffers as undergoing IO than really makes sense - if another backend desires
to read the same blocks, it'll be blocked longer than necessary. So it seems
better to just never cross the boundary.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
As pg_flush_data() doesn't do anything with fsync disabled, there's no point
in tracking the buffer for writeback. Arguably the better fix would be to
change pg_flush_data() to flush data even with fsync off, but that's a
behavioral change, whereas this is just a small optimization.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
Buildfarm members using -Wextra complained about "warning: suggest
braces around empty body in an 'if' statement". Do it gcc's way,
though I see no actual readability benefit in this.
This seems nicer than having to duplicate the logic between
InitProcess() and ProcKill() for which child processes have a
PMChildFlags slot.
Move the MarkPostmasterChildActive() call earlier in InitProcess(),
out of the section protected by the spinlock.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
The code path for launching a dead-end backend because we're out of
slots was not covered by any tests, so add one. (Some tests did hit
the case of launching a dead-end backend because the server is still
starting up, though, so the gap in our test coverage wasn't as big as
it sounds.)
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
There were multiple instances where accidentally adding non-breaking
space (nbsp, U+00A0, 0xc2a0 in UTF-8) to sgml files. This commit adds
additional checking to detect nbsp. You can check the nbsp by:
make -C doc/src/sgml check
or
make -C doc/src/sgml check-nbsp
Authors: Yugo Nagata, Daniel Gustafsson
Reviewed-by: Tatsuo Ishii, Daniel Gustafsson
Discussion: https://postgr.es/m/20240930.153404.202479334310259810.ishii%40postgresql.org
Commit 9e2d870119 placed the check for binary mode and on_error
before default values were inserted, which was not ideal.
This commit moves the check to a more appropriate position
after default values are set.
Additionally, the comment incorrectly mentioned two checks before
inserting defaults, when there are actually three. This commit corrects
that comment.
Author: Atsushi Torikoshi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/8830518a-28ac-43a2-8a11-1676d9a3cdf8@oss.nttdata.com
Previously, when ON_ERROR was set to 'ignore', the COPY command
would skip all rows with data type conversion errors, with no way to
limit the number of skipped rows before failing.
This commit introduces the REJECT_LIMIT option, allowing users to
specify the maximum number of erroneous rows that can be skipped.
If more rows encounter data type conversion errors than allowed by
REJECT_LIMIT, the COPY command will fail with an error, even when
ON_ERROR = 'ignore'.
Author: Atsushi Torikoshi
Reviewed-by: Junwang Zhao, Kirill Reshke, jian he, Fujii Masao
Discussion: https://postgr.es/m/63f99327aa6b404cc951217fa3e61fe4@oss.nttdata.com
The test was unstable in branches 14 and 15 as we were relying on the
number of changes in the table having a toast column to start streaming.
On branches >= 16, we have a GUC debug_logical_replication_streaming which
can stream each change, so the test was stable in those branches.
Change the test to use PREPARE TRANSACTION as that should make the result
consistent and test the code changed in 022564f60c.
Reported-by: Daniel Gustafsson as per buildfarm
Author: Hou Zhijie, Amit Kapila
Backpatch-through: 14
Discussion: https://postgr.es/m/8C2F86AA-981E-4803-B14D-E264C0255330@yesql.se
In commit 8275325a06, I forgot to update password_1.out (an
alternative expected test output file added by commit 3c44e7d8d4),
so this test began failing on machines with FIPS mode enabled.
Commit 1ab67c9dfa, which modified this catalog query so that it
doesn't return temporary relations, forgot to schema-qualify the
operator. A comment earlier in the function implores us to fully
qualify everything in the query:
* Since we execute the constructed query with the default search_path
* (which could be unsafe), everything in this query MUST be fully
* qualified.
This commit fixes that. While at it, add a newline for consistency
with surrounding code.
Reviewed-by: Noah Misch
Discussion: https://postgr.es/m/ZwQJYcuPPUsF0reU%40nathan
Backpatch-through: 12
Several places treat MyStartTime as a "long", which is only 32 bits
wide on some platforms. In reality, MyStartTime is a pg_time_t,
i.e., a signed 64-bit integer. This will lead to interesting bugs
on the aforementioned systems in 2038 when signed 32-bit integers
are no longer sufficient to store Unix time (e.g., "pg_ctl start"
hanging). To fix, ensure that MyStartTime is handled as a 64-bit
value everywhere. (Of course, users will need to ensure that
time_t is 64 bits wide on their system, too.)
Co-authored-by: Max Johnson
Discussion: https://postgr.es/m/CO1PR07MB905262E8AC270FAAACED66008D682%40CO1PR07MB9052.namprd07.prod.outlook.com
Backpatch-through: 12
Rename tab-complete.c to tab-complete.in.c, create the preprocessor
script gen_tabcomplete.pl, and install Makefile/meson.build rules
to create tab-complete.c from tab-complete.in.c. The preprocessor
converts match_previous_words' else-if chain into a switch and
populates tcpatterns[] with the data needed by the driver loop.
The initial HeadMatches/TailMatches/Matches test in each else-if arm
is now performed in a table-driven loop. Where we get a match, the
corresponding switch case is invoked to see if the match succeeds.
(It might not, if there were additional conditions in the original
else-if test.)
The total number of string comparisons done is just about the
same as it was in the previous coding; however, now that we
have table-driven logic underlying the handmade rules, there
is room to improve that. For now I haven't bothered because
tab completion is still plenty fast enough for human use.
If the number of rules keeps increasing, we might someday
need to do more in that area.
The immediate benefit of all this thrashing is that C compilers
frequently don't deal well with long else-if chains. On gcc 8.5.0,
this reduces the compile time of tab-complete.c by about a factor of
four, while MSVC is reported to crash outright with the previous
coding.
Discussion: https://postgr.es/m/2208466.1720729502@sss.pgh.pa.us
Separate out psql_completion's giant else-if chain of *Matches
tests into a new function. Add the infrastructure needed for
table-driven checking of the initial match of each completion
rule. As-is, however, the code continues to operate as it did.
The new behavior applies only if SWITCH_CONVERSION_APPLIED
is #defined, which it is not here. (The preprocessor added
in the next patch will add a #define for that.)
The first and last couple of bits of psql_completion are not
based on HeadMatches/TailMatches/Matches tests, so they stay
where they are; they won't become part of the switch.
This patch also fixes up a couple of if-conditions that didn't meet
the conditions enumerated in the comment for match_previous_words().
Those restrictions exist to simplify the preprocessor.
Discussion: https://postgr.es/m/2208466.1720729502@sss.pgh.pa.us
This argument matches any number (including zero) of previous words.
Use it to replace the common coding pattern
if (HeadMatches("A", "B") && TailMatches("X", "Y"))
with
if (Matches("A", "B", MatchAnyN, "X", "Y"))
In itself this feature doesn't do much except (arguably) make the
code slightly shorter and more readable. However, it reduces the
number of complex if-condition patterns that have to be dealt with
in the next commits in this series.
While here, restructure the *Matches implementation functions so
that the actual work is done in functions that take a char **
array of pattern strings, and the versions taking variadic arguments
are thin wrappers around the array ones. This simplifies the
new Matches logic considerably. At the end of this patch series,
the array functions will be the only ones that are material to
performance, so having the variadic ones be wrappers makes sense.
Discussion: https://postgr.es/m/2208466.1720729502@sss.pgh.pa.us
Commit 6aa44060a3 removed pg_authid's TOAST table because the only
varlena column is rolpassword, which cannot be de-TOASTed during
authentication because we haven't selected a database yet and
cannot read pg_class. Since that change, attempts to set password
hashes that require out-of-line storage will fail with a "row is
too big" error. This error message might be confusing to users.
This commit places a limit on the length of password hashes so that
attempts to set long password hashes will fail with a more
user-friendly error. The chosen limit of 512 bytes should be
sufficient to avoid "row is too big" errors independent of BLCKSZ,
but it should also be lenient enough for all reasonable use-cases
(or at least all the use-cases we could imagine).
Reviewed-by: Tom Lane, Jonathan Katz, Michael Paquier, Jacob Champion
Discussion: https://postgr.es/m/89e8649c-eb74-db25-7945-6d6b23992394%40gmail.com
During logical decoding of in-progress transactions, we perform the toast
table scan while fetching the default toast value for an attribute. We
forgot to initialize the flag during this scan to indicate that the system
table scan is in progress. We need this flag to ensure that during logical
decoding we never directly access the tableam or heap APIs because we check
for concurrent aborts only in systable_* APIs.
Reported-by: Alexander Lakhin
Author: Takeshi Ideriha, Hou Zhijie
Reviewed-by: Amit Kapila, Hou Zhijie
Backpatch-through: 14
Discussion: https://postgr.es/m/18641-6687273b7f15269d@postgresql.org
The documentation was rather sparse on this matter and there is no
extension in-core that shows how to do it. Adding a small example will
hopefully help newcomers. An advantage of writing things this way is
that the contents are not going to rot because of backend changes.
Author: Phil Eaton
Reviewed-by: Robert Haas, Fabrízio de Royes Mello
Discussion: https://postgr.es/m/CAByiw+r+CS-ojBDP7Dm=9YeOLkZTXVnBmOe_ajK=en8C_zB3_g@mail.gmail.com
This GUC is written as camel-case in most of the documentation and the
GUC table (but not postgresql.conf.sample), and two error messages
hardcoded it with lower case characters. Let's use a style more
consistent.
Most of the noise comes from the regression tests, updated to reflect
the GUC name in these error messages.
Author: Peter Smith
Reviewed-by: Peter Eisentraut, Álvaro Herrera
Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
pg_cursor() supposed that any Portal it finds in the hash table must
have sourceText set up, but there's an edge case where that is not so.
A newly-created Portal has sourceText = NULL, and that doesn't change
until PortalDefineQuery is called. In SPI_cursor_open_internal,
we perform GetCachedPlan between CreatePortal and PortalDefineQuery,
and it's possible for user-defined code to execute during that
planning and cause a fetch from the pg_cursors view, resulting in a
null-pointer-dereference crash. (It looks like the same could happen
in exec_bind_message, but I've not tried to provoke a failure there.)
I considered trying to fix this by setting sourceText sooner, but
there may be instances of this same calling pattern in extensions,
and we couldn't be sure they'd get the memo promptly. It seems
better to redefine pg_cursor as not showing Portals that have
not yet had PortalDefineQuery called on them, which we can do by
just skipping them if sourceText is still NULL.
(Before a1c692358, pg_cursor would instead return a row with NULL
in the statement column. We could revert to that behavior but it
doesn't really seem like a better definition, especially since our
documentation doesn't suggest that the column could be NULL.)
Per report from PetSerAl. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAKygsHTBXLXjwV43kpZa+Cs+XTiaeeJiZdL4cPBm9f4MTdw7wg@mail.gmail.com
Tom Lane