PostgreSQL Weekly News - March 7, 2021

# PostgreSQL Weekly News - March 7, 2021

# PostgreSQL Product News

parquet_s3_fdw 0.1, a foreign data wrapper for parquet files on S3, released.
[https://github.com/pgspider/parquet_s3_fdw/releases/tag/v0.1](https://github.com/pgspider/parquet_s3_fdw/releases/tag/v0.1)

# PostgreSQL Jobs for March

[https://archives.postgresql.org/pgsql-jobs/2021-03/](https://archives.postgresql.org/pgsql-jobs/2021-03/)

# PostgreSQL in the News

Planet PostgreSQL: [https://planet.postgresql.org/](https://planet.postgresql.org/)

PostgreSQL Weekly News is brought to you this week by David Fetter

Submit news and announcements by Sunday at 3:00pm PST8PDT to david(at)fetter(dot)org(dot)

# Applied Patches

Thomas Munro pushed:

- Remove latch.c workaround for Linux < 2.6.27. Commit 82ebbeb0 added a
workaround for systems with no epoll_create1() and EPOLL_CLOEXEC. Linux <
2.6.27 and glibc < 2.9 are long gone. Now seems like a good time to drop the
extra code, because otherwise we'd have to add similar already-dead workaround
code to new patches using XXX_CLOEXEC flags that arrived in the same kernel
release. Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> Discussion:
[https://postgr.es/m/CA%2BhUKGKL_%3DaO%3Dr30N%3Ds9VoDgTqHpRSzePRbA9dkYO7snc7HsxA%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGKL_%3DaO%3Dr30N%3Ds9VoDgTqHpRSzePRbA9dkYO7snc7HsxA%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/d1b90995e8d41df7e59efe48e98f26cd66baba9b](https://git.postgresql.org/pg/commitdiff/d1b90995e8d41df7e59efe48e98f26cd66baba9b)

- Optimize latches to send fewer signals. Don't send signals to processes that
aren't sleeping. Author: Andres Freund <andres(at)anarazel(dot)de> Discussion:
[https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com](https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/c8f3bc2401e7df7b79bae39dd3511c91f825b6a4](https://git.postgresql.org/pg/commitdiff/c8f3bc2401e7df7b79bae39dd3511c91f825b6a4)

- Use SIGURG rather than SIGUSR1 for latches. Traditionally, SIGUSR1 has been
overloaded for ad-hoc signals, procsignal.c signals and latch.c wakeups. Move
that last use over to a new dedicated signal. SIGURG is normally used to
report out-of-band socket data, but PostgreSQL doesn't use that facility. The
signal handler is now installed in all postmaster children by
InitializeLatchSupport(). Those wishing to disconnect from it should call
ShutdownLatchSupport(). Future patches will use this separation of signals to
avoid the need for a signal handler on some operating systems. Discussion:
[https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com](https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/83709a0d5a46559db016c50ded1a95fd3b0d3be6](https://git.postgresql.org/pg/commitdiff/83709a0d5a46559db016c50ded1a95fd3b0d3be6)

- Use signalfd(2) for epoll latches. Cut down on system calls and other
overheads by reading from a signalfd instead of using a signal handler and
self-pipe. Affects Linux sytems, and possibly others including illumos that
implement the Linux epoll and signalfd interfaces. Reviewed-by: Andres Freund
<andres(at)anarazel(dot)de> Discussion:
[https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com](https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/6a2a70a02018d6362f9841cc2f499cc45405e86b](https://git.postgresql.org/pg/commitdiff/6a2a70a02018d6362f9841cc2f499cc45405e86b)

- Use EVFILT_SIGNAL for kqueue latches. Cut down on system calls and other
overheads by waiting for SIGURG explicitly with kqueue instead of using a
signal handler and self-pipe. Affects `*BSD` and macOS systems. This leaves
only the poll implementation with a signal handler and the traditional
self-pipe trick. Discussion:
[https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com](https://postgr.es/m/CA+hUKGJjxPDpzBE0a3hyUywBvaZuC89yx3jK9RFZgfv_KHU7gg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/6148656a0be1c6245fbcfcbbeb87541f1b173162](https://git.postgresql.org/pg/commitdiff/6148656a0be1c6245fbcfcbbeb87541f1b173162)

- Introduce symbolic names for FeBeWaitSet positions. Previously we used 0 and 1
to refer to the socket and latch in far flung parts of the tree, without any
explanation. Also use PGINVALID_SOCKET rather than -1 in a couple of places
that didn't already do that. Reviewed-by: Kyotaro Horiguchi
<horikyota(dot)ntt(at)gmail(dot)com> Discussion:
[https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/a042ba2ba7bb44f191f6f9398da27f04a958a0db](https://git.postgresql.org/pg/commitdiff/a042ba2ba7bb44f191f6f9398da27f04a958a0db)

- Use FeBeWaitSet for walsender.c. This avoids the need to set up and tear down
a fresh WaitEventSet every time we need need to wait. We have to add an
explicit exit on postmaster exit (FeBeWaitSet isn't set up to do that
automatically), so move the code to do that into a new function to avoid
repetition. Reviewed-by: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> (earlier
version) Discussion:
[https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/6230912f23904aa6cb2a1f948ca9b08235b4f54a](https://git.postgresql.org/pg/commitdiff/6230912f23904aa6cb2a1f948ca9b08235b4f54a)

- Use condition variables for ProcSignalBarriers. Instead of a poll/sleep loop,
use a condition variable for precise wake-up whenever a backend's
pss_barrierGeneration advances. Discussion:
[https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com](https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/814f1d8bc395bb9b4c0ae090ceea60adfbeb8e49](https://git.postgresql.org/pg/commitdiff/814f1d8bc395bb9b4c0ae090ceea60adfbeb8e49)

- Allow condition variables to be used in interrupt code. Adjust the condition
variable sleep loop to work correctly when code reached by its internal
CHECK_FOR_INTERRUPTS() call interacts with another condition variable. There
are no such cases currently, but a proposed patch would do this. Discussion:
[https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com](https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/f5a5773a9dc4185414fe538525e20d8512c2ba35](https://git.postgresql.org/pg/commitdiff/f5a5773a9dc4185414fe538525e20d8512c2ba35)

- Remove obsolete comment for WaitForProcSignalBarrier(). Commit 814f1d8b
removed the behavior described. Reported-by: Amit Kapila
<amit(dot)kapila16(at)gmail(dot)com>
[https://git.postgresql.org/pg/commitdiff/bd69ddfcdbf650f11af4317f3f6686c012cf66d0](https://git.postgresql.org/pg/commitdiff/bd69ddfcdbf650f11af4317f3f6686c012cf66d0)

- Add sort_template.h for making sort functions. Move our qsort implementation
into a header that can be used to define specialized functions for better
performance and reduced duplication. Reviewed-by: Daniel Gustafsson
<daniel(at)yesql(dot)se> Discussion:
[https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/0a1f1d3cac6baaa3744b89336673caba702f7628](https://git.postgresql.org/pg/commitdiff/0a1f1d3cac6baaa3744b89336673caba702f7628)

- Use sort_template.h for qsort() and qsort_arg(). Reduce duplication by using
the new template. Reviewed-by: Daniel Gustafsson <daniel(at)yesql(dot)se>
Discussion:
[https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/f374f4d66425060158d3c743dc6fb16cc0a2756a](https://git.postgresql.org/pg/commitdiff/f374f4d66425060158d3c743dc6fb16cc0a2756a)

- Use sort_template.h for qsort_tuple() and qsort_ssup(). Replace the Perl code
previously used to generate specialized sort functions with sort_template.h.
Reviewed-by: Daniel Gustafsson <daniel(at)yesql(dot)se> Discussion:
[https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com](https://postgr.es/m/CA%2BhUKGJ2-eaDqAum5bxhpMNhvuJmRDZxB_Tow0n-gse%2BHG0Yig%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/8eda3eba3063d619214b59f7bc7ecfc09c21b93a](https://git.postgresql.org/pg/commitdiff/8eda3eba3063d619214b59f7bc7ecfc09c21b93a)

Amit Kapila pushed:

- Update the docs and comments for decoding of prepared xacts. Commit a271a1b50e
introduced decoding at prepare time in ReorderBuffer. This can lead to
deadlock for out-of-core logical replication solutions that uses this feature
to build distributed 2PC in case such transactions lock [user] catalog tables
exclusively. They need to inform users to not have locks on catalog tables
(via explicit LOCK command) in such transactions. Reported-by: Andres Freund
Discussion:
[https://postgr.es/m/20210222222847.tpnb6eg3yiykzpky@alap3.anarazel.de](https://postgr.es/m/20210222222847.tpnb6eg3yiykzpky@alap3.anarazel.de)
[https://git.postgresql.org/pg/commitdiff/b4e3dc7fd420cdc2287f30a638c4affd071f01b2](https://git.postgresql.org/pg/commitdiff/b4e3dc7fd420cdc2287f30a638c4affd071f01b2)

- Update docs of logical replication for commit ce0fdbfe97. Forgot to update the
logical replication configuration settings page. After commit ce0fdbfe97,
table synchronization workers also started using replication origins to track
the progress and the same should be reflected in docs. Author: Amit Kapila
Discussion:
[https://postgr.es/m/CAA4eK1KkbppndxxRKbaT2sXrLkdPwy44F4pjEZ0EDrVjD9MPjQ@mail.gmail.com](https://postgr.es/m/CAA4eK1KkbppndxxRKbaT2sXrLkdPwy44F4pjEZ0EDrVjD9MPjQ@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/cf54e04b9e29a13c5e7c2386c5e2ff785e830414](https://git.postgresql.org/pg/commitdiff/cf54e04b9e29a13c5e7c2386c5e2ff785e830414)

- Avoid repeated decoding of prepared transactions after a restart. In commit
a271a1b50e, we allowed decoding at prepare time and the prepare was decoded
again if there is a restart after decoding it. It was done that way because we
can't distinguish between the cases where we have not decoded the prepare
because it was prior to consistent snapshot or we have decoded it earlier but
restarted. To distinguish between these two cases, we have introduced an
initial_consistent_point at the slot level which is an LSN at which we found a
consistent point at the time of slot creation. This is also the point where we
have exported a snapshot for the initial copy. So, prepare transaction prior
to this point are sent along with commit prepared. This commit bumps
SNAPBUILD_VERSION because of change in SnapBuild. It will break existing slots
which is fine in a major release. Author: Ajin Cherian, based on idea by
Andres Freund Reviewed-by: Amit Kapila and Vignesh C Discussion:
[https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com](https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com)
[https://git.postgresql.org/pg/commitdiff/8bdb1332eb51837c15a10a972c179b84f654279e](https://git.postgresql.org/pg/commitdiff/8bdb1332eb51837c15a10a972c179b84f654279e)

- Add option to enable two_phase commits via pg_create_logical_replication_slot.
Commit 0aa8a01d04 extends the output plugin API to allow decoding of prepared
xacts and allowed the user to enable/disable the two-phase option via
pg_logical_slot_get_changes(). This can lead to a problem such that the first
time when it gets changes via pg_logical_slot_get_changes() without two_phase
option enabled it will not get the prepared even though prepare is after
consistent snapshot. Now next time during getting changes, if the two_phase
option is enabled it can skip prepare because by that time start decoding
point has been moved. So the user will only get commit prepared. Allow to
enable/disable this option at the create slot time and default will be false.
It will break the existing slots which is fine in a major release. Author:
Ajin Cherian Reviewed-by: Amit Kapila and Vignesh C Discussion:
[https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com](https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com)
[https://git.postgresql.org/pg/commitdiff/19890a064ebf53dedcefed0d8339ed3d449b06e6](https://git.postgresql.org/pg/commitdiff/19890a064ebf53dedcefed0d8339ed3d449b06e6)

- Clarify the usage of max_replication_slots on the subscriber side. It was not
clear in the docs that the max_replication_slots is also used to track
replication origins on the subscriber side. Author: Paul Martinez
Reviewed-by: Amit Kapila Backpatch-through: 10 where logical replication was
introduced Discussion:
[https://postgr.es/m/CACqFVBZgwCN_pHnW6dMNCrOS7tiHCw6Retf_=U2Vvj3aUSeATw@mail.gmail.com](https://postgr.es/m/CACqFVBZgwCN_pHnW6dMNCrOS7tiHCw6Retf_=U2Vvj3aUSeATw@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/8af3c233e423e106a5121000ecd92abf57c11704](https://git.postgresql.org/pg/commitdiff/8af3c233e423e106a5121000ecd92abf57c11704)

Andres Freund pushed:

- Fix recovery test hang in 021_row_visibility.pl on windows. The psql processes
were not explicitly killed (but would eventually exit due postgres shutting
down). For some reason windows perl doesn't like that, resulting in errors
like Warning: unable to close filehandle GEN20 properly: Bad file descriptor
during global destruction. The test was introduced in d6734a897e3, so no
backpatching necessary.
[https://git.postgresql.org/pg/commitdiff/1e6e40447115ca7b4749d7d117b81b016ee5e2c2](https://git.postgresql.org/pg/commitdiff/1e6e40447115ca7b4749d7d117b81b016ee5e2c2)

Tom Lane pushed:

- Improve reporting for syntax errors in multi-line JSON data. Point to the
specific line where the error was detected; the previous code tended to
include several preceding lines as well. Avoid re-scanning the entire input to
recompute which line that was. Simplify the logic a bit. Add test cases.
Simon Riggs and Hamid Akhtar, reviewed by Daniel Gustafsson and myself
Discussion:
[`https://postgr.es/m/CANbhV-EPBnXm3MF_TTWBwwqgn1a1Ghmep9VHfqmNBQ8BT0f+_g@mail.gmail.com`](https://postgr.es/m/CANbhV-EPBnXm3MF_TTWBwwqgn1a1Ghmep9VHfqmNBQ8BT0f+_g@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/ffd3944ab9d481906137bc7d20f5325a2bd68acc](https://git.postgresql.org/pg/commitdiff/ffd3944ab9d481906137bc7d20f5325a2bd68acc)

- Fix semantics of regular expression back-references. POSIX defines the
behavior of back-references thus: The back-reference expression '\n'
shall match the same (possibly empty) string of characters as was matched
by a subexpression enclosed between "\(" and "\)" preceding the '\n'. As
far as I can see, the back-reference is supposed to consider only the data
characters matched by the referenced subexpression. However, because our
engine copies the NFA constructed from the referenced subexpression, it
effectively enforces any constraints therein, too. As an example, '(^.)\1'
ought to match 'xx', or any other string starting with two occurrences of the
same character; but in our code it does not, and indeed can't match anything,
because the '^' anchor constraint is included in the backref's copied NFA. If
POSIX intended that, you'd think they'd mention it. Perl for one doesn't act
that way, so it's hard to conclude that this isn't a bug. Fix by modifying
the backref's NFA immediately after it's copied from the reference, replacing
all constraint arcs by EMPTY arcs so that the constraints are treated as
automatically satisfied. This still allows us to enforce matching rules that
depend only on the data characters; for example, in `'(^\d+).*\1'` the NFA
matching step will still know that the backref can only match strings of
digits. Perhaps surprisingly, this change does not affect the results of any
of a rather large corpus of real-world regexes. Nonetheless, I would not
consider back-patching it, since it's a clear compatibility break. Patch by
me, reviewed by Joel Jacobson Discussion:
[https://postgr.es/m/661609.1614560029@sss.pgh.pa.us](https://postgr.es/m/661609.1614560029@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/4aea704a5bfd4b5894a268499369ccab89940c9c](https://git.postgresql.org/pg/commitdiff/4aea704a5bfd4b5894a268499369ccab89940c9c)

- Improve performance of regular expression back-references. In some cases, at
the time that we're doing an NFA-based precheck of whether a backref
subexpression can match at a particular place in the string, we already know
which substring the referenced subexpression matched. If so, we might as well
forget about the NFA and just compare the substring; this is faster and it
gives an exact rather than approximate answer. In general, this optimization
can help while we are prechecking within the second child expression of a
concat node, while the capture was within the first child expression; then the
substring was saved during cdissect() of the first child and will be available
to NFA checks done while cdissect() recurses into the second child. It can
help quite a lot if the tree looks like concat /
\ capture concat / \ expensive
stuff backref as we will be able to avoid recursively dissecting the
"expensive stuff" before discovering that the backref isn't satisfied with a
particular midpoint that the lower concat node is testing. This doesn't help
if the concat tree is left-deep, as the capture node won't get set soon enough
(and it's hard to fix that without changing the engine's match behavior).
Fortunately, right-deep concat trees are the common case. Patch by me,
reviewed by Joel Jacobson Discussion:
[https://postgr.es/m/661609.1614560029@sss.pgh.pa.us](https://postgr.es/m/661609.1614560029@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/0c3405cf11a12da1a4278c6833f4d979fe06c866](https://git.postgresql.org/pg/commitdiff/0c3405cf11a12da1a4278c6833f4d979fe06c866)

- Suppress unnecessary regex subre nodes in a couple more cases. This extends
the changes made in commit cebc1d34e, teaching parseqatom() to generate fewer
or cheaper subre nodes in some edge cases. The case of interest here is a
quantified atom that is "messy" only because it has greediness opposite to
what preceded it (whereas captures and backrefs are intrinsically messy). In
this case we don't need an iteration node, since we don't care where the
sub-matches of the quantifier are; and we might also not need a second
concatenation node. This seems of only marginal real-world use according to
my testing, but I wanted to get it in before wrapping up this series of regex
performance fixes. Discussion:
[https://postgr.es/m/1340281.1613018383@sss.pgh.pa.us](https://postgr.es/m/1340281.1613018383@sss.pgh.pa.us)
[https://git.postgresql.org/pg/commitdiff/4604f83fdfe030a2f1984159ede5270c1d825310](https://git.postgresql.org/pg/commitdiff/4604f83fdfe030a2f1984159ede5270c1d825310)

- Mark default_transaction_read_only as GUC_REPORT. This allows clients to find
out the setting at connection time without having to expend a query round trip
to do so; which is helpful when trying to identify read/write servers. (One
must also look at in_hot_standby, but that's already GUC_REPORT, cf
bf8a662c9.) Modifying libpq to make use of this will come soon, but I felt it
cleaner to push the server change separately. Haribabu Kommi, Greg Nancarrow,
Vignesh C; reviewed at various times by Laurenz Albe, Takayuki Tsunakawa,
Peter Smith. Discussion:
[https://postgr.es/m/CAF3+xM+8-ztOkaV9gHiJ3wfgENTq97QcjXQt+rbFQ6F7oNzt9A@mail.gmail.com](https://postgr.es/m/CAF3+xM+8-ztOkaV9gHiJ3wfgENTq97QcjXQt+rbFQ6F7oNzt9A@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/d16f8c8e416d288bd4734ed5f14076b62ec8d153](https://git.postgresql.org/pg/commitdiff/d16f8c8e416d288bd4734ed5f14076b62ec8d153)

- Extend the abilities of libpq's target_session_attrs parameter. In addition to
the existing options of "any" and "read-write", we now support "read-only",
"primary", "standby", and "prefer-standby". "read-write" retains its previous
meaning of "transactions are read-write by default", and "read-only" inverts
that. The other three modes test specifically for hot-standby status, which
is not quite the same thing. (Setting default_transaction_read_only on a
primary server renders it read-only to this logic, but not a standby.)
Furthermore, if talking to a v14 or later server, no extra network round trip
is needed to detect the session's status; the GUC_REPORT variables delivered
by the server are enough. When talking to an older server, a SHOW or SELECT
query is issued to detect session read-only-ness or server hot-standby state,
as needed. Haribabu Kommi, Greg Nancarrow, Vignesh C, Tom Lane; reviewed at
various times by Laurenz Albe, Takayuki Tsunakawa, Peter Smith. Discussion:
[https://postgr.es/m/CAF3+xM+8-ztOkaV9gHiJ3wfgENTq97QcjXQt+rbFQ6F7oNzt9A@mail.gmail.com](https://postgr.es/m/CAF3+xM+8-ztOkaV9gHiJ3wfgENTq97QcjXQt+rbFQ6F7oNzt9A@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/ee28cacf619f4d9c23af5a80e1171a5adae97381](https://git.postgresql.org/pg/commitdiff/ee28cacf619f4d9c23af5a80e1171a5adae97381)

- Silence perlcritic warning in commit ee28cacf6. Per buildfarm; this fix is
from Michael Paquier (vignesh C proposed nearly the same). Discussion:
[https://postgr.es/m/YD8IZ9OKfUf9X1eF@paquier.xyz](https://postgr.es/m/YD8IZ9OKfUf9X1eF@paquier.xyz)
[https://git.postgresql.org/pg/commitdiff/d422a2a94b1e7a7bb25da9d5511fffff750c3f21](https://git.postgresql.org/pg/commitdiff/d422a2a94b1e7a7bb25da9d5511fffff750c3f21)

- Make test_target_session_attrs more robust against connection failure. Feed
the desired command to psql via "-c" not stdin, else Perl may complain that it
can't push stdin to an already-failed psql process, as seen in intermittent
buildfarm failures. Make some minor cosmetic improvements while at it.
Before commit ee28cacf6 we had no tests here that expected failure to connect,
so there seems no need for a back-patch. Discussion:
[https://postgr.es/m/CALDaNm2mo8YED=M2ZJKGf1U3F3mw6SaQuLXWCK8rZP6sECYcrA@mail.gmail.com](https://postgr.es/m/CALDaNm2mo8YED=M2ZJKGf1U3F3mw6SaQuLXWCK8rZP6sECYcrA@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/3769e11a31831fc2f3bd4c4a24b4f45c352fb8fb](https://git.postgresql.org/pg/commitdiff/3769e11a31831fc2f3bd4c4a24b4f45c352fb8fb)

- Add trim_array() function. This has been in the SQL spec since 2008. It's a
pretty thin wrapper around the array slice functionality, but the spec says we
should have it, so here it is. Vik Fearing, reviewed by Dian Fay Discussion:
[https://postgr.es/m/fc92ce17-9655-8ff1-c62a-4dc4c8ccd815@postgresfriends.org](https://postgr.es/m/fc92ce17-9655-8ff1-c62a-4dc4c8ccd815@postgresfriends.org)
[https://git.postgresql.org/pg/commitdiff/0a687c8f103d217ff1ca8c34a644b380d89bb0ad](https://git.postgresql.org/pg/commitdiff/0a687c8f103d217ff1ca8c34a644b380d89bb0ad)

- Remove deprecated containment operators for contrib types. Since PG 8.2, @ and
~ have been deprecated aliases for the containment operators @> and <@. It
seems like enough time has passed to actually remove them, so do so. This
completes the project begun in commit 2f70fdb06. Note that in the core types,
the relation to the preferred operator names was reversed from what it is in
these contrib modules. The confusion that induced was a large part of the
reason for deprecation. Justin Pryzby Discussion:
[https://postgr.es/m/20201027032511.GF9241@telsasoft.com](https://postgr.es/m/20201027032511.GF9241@telsasoft.com)
[https://git.postgresql.org/pg/commitdiff/112d411fbeb56afd18c117e20b524a86afc9aba5](https://git.postgresql.org/pg/commitdiff/112d411fbeb56afd18c117e20b524a86afc9aba5)

- Doc: remove obsolete entries in table of BRIN strategy numbers. See commit
591d282e8. Noted by Justin Pryzby Discussion:
[https://postgr.es/m/20201027032511.GF9241@telsasoft.com](https://postgr.es/m/20201027032511.GF9241@telsasoft.com)
[https://git.postgresql.org/pg/commitdiff/0ce4cd04da558178b0186057b721c50a00b7a945](https://git.postgresql.org/pg/commitdiff/0ce4cd04da558178b0186057b721c50a00b7a945)

- Add binary I/O capability for cube datatype. We can adjust the
not-yet-released cube--1.4--1.5.sql upgrade rather than making a whole new
version. KaiGai Kohei Discussion:
[https://postgr.es/m/CAOP8fzZO4y60QPTK=RGDXeVeVHV9tLHKOsh7voUOoUouVCPV8A@mail.gmail.com](https://postgr.es/m/CAOP8fzZO4y60QPTK=RGDXeVeVHV9tLHKOsh7voUOoUouVCPV8A@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/1265a9c8f871cfa5aea4d607b1ab72b45b96dbb7](https://git.postgresql.org/pg/commitdiff/1265a9c8f871cfa5aea4d607b1ab72b45b96dbb7)

Michaël Paquier pushed:

- doc: Mention archive_command failure handling on signals. The behavior is
similar to restore_command, which was already documented for the restore part,
but not the archive part. Author: Benoit Lobréau Reviewed-by: Julien Rouhaud
Discussion:
[https://postgr.es/m/CAPE8EZ7akCzc1hWohA4AcbmKtHh9rcWAB5MStOeZD2+9jC+hLQ@mail.gmail.com](https://postgr.es/m/CAPE8EZ7akCzc1hWohA4AcbmKtHh9rcWAB5MStOeZD2+9jC+hLQ@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/8c1b6a186d420de863d1334c8917dcd047a7845a](https://git.postgresql.org/pg/commitdiff/8c1b6a186d420de863d1334c8917dcd047a7845a)

- doc: Improve description of data checksums. This partially reverts bcf2667
that got incorrectly merged, and this improves the wording of the
documentation that existed before that. Per discussion with Justin Pryzby.
Discussion:
[https://postgr.es/m/20210301004647.GF20769@telsasoft.com](https://postgr.es/m/20210301004647.GF20769@telsasoft.com)
[https://git.postgresql.org/pg/commitdiff/bd1b8d0ef2eb5f2a8765fbb3b74e0262c9983942](https://git.postgresql.org/pg/commitdiff/bd1b8d0ef2eb5f2a8765fbb3b74e0262c9983942)

- Simplify code to switch pg_class.relrowsecurity in tablecmds.c. The same code
pattern was repeated twice to enable or disable ROW LEVEL SECURITY with an
ALTER TABLE command. This makes the code slightly cleaner. Author: Justin
Pryzby Reviewed-by: Zhihong Yu Discussion:
[https://postgr.es/m/20210228211854.GC20769@telsasoft.com](https://postgr.es/m/20210228211854.GC20769@telsasoft.com)
[https://git.postgresql.org/pg/commitdiff/fabde52fab976ff782d77c80b8e2614f94f9dce1](https://git.postgresql.org/pg/commitdiff/fabde52fab976ff782d77c80b8e2614f94f9dce1)

- Fix duplicated test case in TAP tests of reindexdb. The same test for REINDEX
(VERBOSE) was done twice, while it is clear that the second test should use
--concurrently. Issue introduced in 5dc92b8, for what looks like a copy-paste
mistake. Reviewed-by: Mark Dilger Discussion:
[https://postgr.es/m/A7AE97EA-F4B0-4CAB-8FFF-3FECD31F9D63@enterprisedb.com](https://postgr.es/m/A7AE97EA-F4B0-4CAB-8FFF-3FECD31F9D63@enterprisedb.com)
Backpatch-through: 12
[https://git.postgresql.org/pg/commitdiff/c5530d8474a482d32c0d9bb099707d9a8e117f96](https://git.postgresql.org/pg/commitdiff/c5530d8474a482d32c0d9bb099707d9a8e117f96)

- Add --tablespace option to reindexdb. This option provides REINDEX
(TABLESPACE) for reindexdb, applying the tablespace value given by the caller
to all the REINDEX queries generated. While on it, this commit adds some
tests for REINDEX TABLESPACE, with and without CONCURRENTLY, when run on toast
indexes and tables. Such operations are not allowed, and toast relation names
are not stable enough to be part of the main regression test suite (even if
using a PL function with a TRY/CATCH logic, as CONCURRENTLY could not be
tested). Author: Michael Paquier Reviewed-by: Mark Dilger, Daniel Gustafsson
Discussion:
[https://postgr.es/m/YDiaDMnzLICqeukl@paquier.xyz](https://postgr.es/m/YDiaDMnzLICqeukl@paquier.xyz)
[https://git.postgresql.org/pg/commitdiff/57e6db706e81fd2609fa385677e6ae72471822fe](https://git.postgresql.org/pg/commitdiff/57e6db706e81fd2609fa385677e6ae72471822fe)

- Add support for PROVE_TESTS and PROVE_FLAGS in MSVC scripts. These can be set
in buildenv.pl or a "set" command within a Windows terminal. The MSVC script
vcregress.pl parses the values available in the environment to build the
resulting prove commands, and the parsing of PROVE_TESTS is able to handle
name patterns in the same way as other platforms. Not specifying those
environment values makes vcregress.pl fall back to the previous default, with
no extra flags for the prove command, and all the tests run within t/.
Author: Michael Paquier Reviewed-by: Juan José Santamaría Flecha, Julien
Rouhaud Discussion:
[https://postgr.es/m/YD9GigwHoL6lFY2y@paquier.xyz](https://postgr.es/m/YD9GigwHoL6lFY2y@paquier.xyz)
[https://git.postgresql.org/pg/commitdiff/5bca69a76b3046a85c60c48271c1831fd5affa51](https://git.postgresql.org/pg/commitdiff/5bca69a76b3046a85c60c48271c1831fd5affa51)

- doc: Add backlinks to progress reporting documentation. Previously, the only
place where progress reports were mentioned is in the section for monitoring
dedicated to its catalogs. This makes the progress reporting more
discoverable, by adding links from the pages of the commands supporting
progress reports to their related catalog views. Author: Matthias van de
Meent Reviewed-by: Justin Pryzby, Bharath Rupireddy, Josef Šimánek, Tomas
Vondra Discussion:
[https://postgr.es/m/CAEze2WiOcgdH4aQA8NtZq-4dgvnJzp8PohdeKchPkhMY-jWZXA@mail.gmail.com](https://postgr.es/m/CAEze2WiOcgdH4aQA8NtZq-4dgvnJzp8PohdeKchPkhMY-jWZXA@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/8a8f4d8ede288c2a29105f4708e22ce7f3526149](https://git.postgresql.org/pg/commitdiff/8a8f4d8ede288c2a29105f4708e22ce7f3526149)

- pgbench: Simplify some port, host, user and dbname assignments. Using pgbench
in an environment with both PGPORT and PGUSER set would have caused the
generation of a debug log with an incorrect database name due to an oversight
in 412893b. Not specifying user, port and/or database using the option
switches, without their respective environment variables, generated a log
entry with empty strings, which was rather useless. This commit fixes this
set of issues by simplifying the logic grabbing the connection information,
removing a set of getenv() calls that emulated what libpq already does. The
faulty debug log now directly uses the information from the libpq connection,
and it gets generated after the connection to the backend is completed, not
before it (in the event of a failure libpq would complain with more
information about the connection attempt so the log is not really useful
before anyway). Author: Kota Miyake Reviewed-by: Fujii Masao, Michael Paquier
Discussion:
[https://postgr.es/m/026b3ae6fc339a18394d053c32a4463d@oss.nttdata.com](https://postgr.es/m/026b3ae6fc339a18394d053c32a4463d@oss.nttdata.com)
[https://git.postgresql.org/pg/commitdiff/f1516ad7b3a9645a316846fa7b2229163bc55907](https://git.postgresql.org/pg/commitdiff/f1516ad7b3a9645a316846fa7b2229163bc55907)

Álvaro Herrera pushed:

- Use native path separators to pg_ctl in initdb. On Windows, CMD.EXE allegedly
does not run a command that uses forward slashes, so let's convert the path to
use backslashes instead. Backpatch to 10. Author: Nitin Jadhav
<nitinjadhavpostgres(at)gmail(dot)com> Reviewed-by: Juan José Santamaría Flecha
<juanjo(dot)santamaria(at)gmail(dot)com> Discussion:
[https://postgr.es/m/CAMm1aWaNDuaPYFYMAqDeJrZmPtNvLcJRS++CcZWY8LT6KcoBZw@mail.gmail.com](https://postgr.es/m/CAMm1aWaNDuaPYFYMAqDeJrZmPtNvLcJRS++CcZWY8LT6KcoBZw@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/75dbfe4ca70d5b7a83f61b0a66a0a14ad0b739ed](https://git.postgresql.org/pg/commitdiff/75dbfe4ca70d5b7a83f61b0a66a0a14ad0b739ed)

Peter Geoghegan pushed:

- Fix nbtree page deletion error messages. Adjust some "can't happen" error
messages that assumed that the page deletion target page must be a half-dead
page. This assumption was wrong in the case of an internal target page.
Simply refer to these pages as the target page instead. Internal pages are
never marked half-dead. There is exactly one half-dead page for each subtree
undergoing deletion. The half-dead page is also the target subtree's
leaf-level page. This has been the case since commit efada2b8, which totally
overhauled nbtree page deletion.
[https://git.postgresql.org/pg/commitdiff/3d8d5787a358156edaa7782f0c88e231af974a01](https://git.postgresql.org/pg/commitdiff/3d8d5787a358156edaa7782f0c88e231af974a01)

- nbtree page deletion: Add leaftopparent assertion. Add documenting assertion.
This makes it easier to follow how we maintain the top parent link in target
subtree's half-dead/leaf level page.
[https://git.postgresql.org/pg/commitdiff/5b2f2af3d9d57626b9052a05337e32ad1399093d](https://git.postgresql.org/pg/commitdiff/5b2f2af3d9d57626b9052a05337e32ad1399093d)

Peter Eisentraut pushed:

- Some copy-editing of GUC descriptions.
[https://git.postgresql.org/pg/commitdiff/e527a99055154bb7fe6ed67f0417a67cf11fa056](https://git.postgresql.org/pg/commitdiff/e527a99055154bb7fe6ed67f0417a67cf11fa056)

- pg_upgrade: Check version of target cluster binaries. This expands the binary
validation in pg_upgrade with a version check per binary to ensure that the
target cluster installation only contains binaries from the target version.
In order to reduce duplication, validate_exec is exported from port.h and the
local copy in pg_upgrade is removed. Author: Daniel Gustafsson
<daniel(at)yesql(dot)se> Discussion:
[https://www.postgresql.org/message-id/flat/9328(dot)1552952117(at)sss(dot)pgh(dot)pa(dot)us](https://www.postgresql.org/message-id/flat/9328(dot)1552952117(at)sss(dot)pgh(dot)pa(dot)us)
[https://git.postgresql.org/pg/commitdiff/f06b1c598254f8adb2b7f51d6a7685618a7fb121](https://git.postgresql.org/pg/commitdiff/f06b1c598254f8adb2b7f51d6a7685618a7fb121)

- pg_upgrade: Fix oversight in version checking. Mistake in
f06b1c598254f8adb2b7f51d6a7685618a7fb121: We should only check the version of
the binaries in the target installation. The source installation can of
course be of a different version. Reviewed-by: Daniel Gustafsson
<daniel(at)yesql(dot)se> Discussion:
[https://www.postgresql.org/message-id/flat/E1lHNKN-0005IC-V6%40gemulon.postgresql.org](https://www.postgresql.org/message-id/flat/E1lHNKN-0005IC-V6%40gemulon.postgresql.org)
[https://git.postgresql.org/pg/commitdiff/040af779382e8e4797242c49b93a5a8f9b79c370](https://git.postgresql.org/pg/commitdiff/040af779382e8e4797242c49b93a5a8f9b79c370)

- Add bit_xor aggregate function. This can be used as a checksum for unordered
sets. bit_and and bit_or already exist. Author: Alexey Bashtanov
<bashtanov(at)imap(dot)cc> Reviewed-by: Ibrar Ahmed <ibrar(dot)ahmad(at)gmail(dot)com>
Discussion:
[https://www.postgresql.org/message-id/flat/9d4582ae-ecfc-3a13-2238-6ab5a37c1f41(at)imap(dot)cc](https://www.postgresql.org/message-id/flat/9d4582ae-ecfc-3a13-2238-6ab5a37c1f41(at)imap(dot)cc)
[https://git.postgresql.org/pg/commitdiff/f9a0392e1cf36179c984f655a6589734b8dd7468](https://git.postgresql.org/pg/commitdiff/f9a0392e1cf36179c984f655a6589734b8dd7468)

Heikki Linnakangas pushed:

- Remove server and libpq support for old FE/BE protocol version 2. Protocol
version 3 was introduced in PostgreSQL 7.4. There shouldn't be many clients or
servers left out there without version 3 support. But as a courtesy, I kept
just enough of the old protocol support that we can still send the
"unsupported protocol version" error in v2 format, so that old clients can
display the message properly. Likewise, libpq still understands v2
ErrorResponse messages when establishing a connection. The impetus to do this
now is that I'm working on a patch to COPY FROM, to always prefetch some data.
We cannot do that safely with the old protocol, because it requires parsing
the input one byte at a time to detect the end-of-copy marker. Reviewed-by:
Tom Lane, Alvaro Herrera, John Naylor Discussion:
[https://www.postgresql.org/message-id/9ec25819-0a8a-d51a-17dc-4150bb3cca3b%40iki.fi](https://www.postgresql.org/message-id/9ec25819-0a8a-d51a-17dc-4150bb3cca3b%40iki.fi)
[https://git.postgresql.org/pg/commitdiff/3174d69fb96a66173224e60ec7053b988d5ed4d9](https://git.postgresql.org/pg/commitdiff/3174d69fb96a66173224e60ec7053b988d5ed4d9)

- Avoid extra newline in errors received in FE protocol version 2. Contrary to
what the comment said, the postmaster does in fact end all its messages in a
newline, since server version 7.2. Be tidy and don't add an extra newline if
the error message already has one. Discussion:
[https://www.postgresql.org/message-id/CAFBsxsEdgMXc%2BtGfEy9Y41i%3D5pMMjKeH8t8vSAypR3ZnAoQnHg%40mail.gmail.com](https://www.postgresql.org/message-id/CAFBsxsEdgMXc%2BtGfEy9Y41i%3D5pMMjKeH8t8vSAypR3ZnAoQnHg%40mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/85d94c575302644e7ddb4392c3bda572f981ec34](https://git.postgresql.org/pg/commitdiff/85d94c575302644e7ddb4392c3bda572f981ec34)

Fujii Masao pushed:

- Remove redundant getenv() for PGUSER, in psql help. Previously psql obtained
the value of PGUSER twice to display a default user in its help message.
Author: Kota Miyake Reviewed-by: Nitin Jadhav, Fujii Masao Discussion:
[https://postgr.es/m/2a3c612babdd6ed63a9d877bb575d793@oss.nttdata.com](https://postgr.es/m/2a3c612babdd6ed63a9d877bb575d793@oss.nttdata.com)
[https://git.postgresql.org/pg/commitdiff/4a4241e15b246663fc44b5e5355bc6d19c6d2aa6](https://git.postgresql.org/pg/commitdiff/4a4241e15b246663fc44b5e5355bc6d19c6d2aa6)

Andrew Dunstan pushed:

- Close psql processes gracefully in recovery tests. Under windows, psql
processes need to be ended explicitly, or the TAP tests hang. However, the
recovery tests were doing this via IPC::Run::kill_kill(), which causes other
major problems on Windows. We solve this by instead sending '\q' to psql so
it quits of its own accord, and then simply waiting for it. This means we can
now run almost all the recovery tests on all Windows platforms. Discussion:
[https://postgr.es/m/20210301200715.tdjpuesfzebpffgn@alap3.anarazel.de](https://postgr.es/m/20210301200715.tdjpuesfzebpffgn@alap3.anarazel.de)
[https://git.postgresql.org/pg/commitdiff/d3676a2e9f10a0972c6d6649235c1c7492cd6dea](https://git.postgresql.org/pg/commitdiff/d3676a2e9f10a0972c6d6649235c1c7492cd6dea)

Magnus Hagander pushed:

- Improve docs on updatable views. Introduce the options before going into
details, and add a link to the CREATE TRIGGER documentation. Author: David
Johnston Reviewed-By: Anastasia Lubennikova Discussion:
[https://postgr.es/m/CAKFQuwYLLRhheo0_Y4Jp=vJ_YDsz1KoRuTpX1A_bUxmHTmLe-A@mail.gmail.com](https://postgr.es/m/CAKFQuwYLLRhheo0_Y4Jp=vJ_YDsz1KoRuTpX1A_bUxmHTmLe-A@mail.gmail.com)
[https://git.postgresql.org/pg/commitdiff/e045565dae4b2368ba812d60ef0fb7f927fe2646](https://git.postgresql.org/pg/commitdiff/e045565dae4b2368ba812d60ef0fb7f927fe2646)

- Clarify that CREATEROLE roles are considered Administrators. Author: Michael
Banck Reviewed-By: Robert Treat Discussion:
[https://postgr.es/m/2160a5071a7bb5339055b04a8cad81a822be9d8d.camel@credativ.de](https://postgr.es/m/2160a5071a7bb5339055b04a8cad81a822be9d8d.camel@credativ.de)
[https://git.postgresql.org/pg/commitdiff/30b26dfac7db2fc76dafaa8a6c459871bfcd100e](https://git.postgresql.org/pg/commitdiff/30b26dfac7db2fc76dafaa8a6c459871bfcd100e)

# Pending Patches

Pavel Stěhule sent in another revision of a patch to implement schema variables.

Maxim Orlov sent in a patch to fix an infelicity between TLS and multiple hosts
in libpq connect strings.

Thomas Munro sent in two more revisions of a patch to add a condition variable
for walreceiver state, another for for recovery pause/resume, and poll the
postmaster less frequently in recovery.

Ajin Cherian and Amit Kapila traded patches to add an option to enable two_phase
commits via pg_create_logical_replication_slot.

Michael Banck sent in a patch to add a --create-only option to
pg_dump/pg_dumpall.

Michaël Paquier sent in another revision of a patch to clarify the documentation
of signal handling in the archiver.

Etsuro Fujita sent in another revision of a patch to implement asynchronous
append on postgres_fdw nodes.

Peter Eisentraut sent in another revision of a patch to deal with macOS SIP in
builds.

Laurenz Albe and Amit Langote traded patches to allow setting parallel_workers
on partitioned tables.

Joel Jacobson sent in three revisions of a patch to implement
regexp_positions(), which returns the starting and ending positions of each
match.

Thomas Munro sent in two more revisions of a patch to provide a new optional GUC
that can be used to check whether the client connection has gone away
periodically while running very long queries.

Paul Förster sent in another revision of a patch to mention URIs and services in
psql --help's output.

Peter Smith and Ajin Cherian traded patches to implement logical decoding of
two-phase transactions.

Greg Nancarrow and Amit Kapila traded patches to enable parallel SELECT for
"INSERT INTO ... SELECT ...", add a new boolean GUC, enable_parallel_dml, and a
similar table option, parallel_dml_enabled.

Dian M Fay sent in two revisions of a patch to suppress explicit casts of text
constants in postgres_fdw when the other side of a binary OpExpr is also text.

Dilip Kumar sent in three more revisions of a patch to add a compression method
option for tables.

Julien Rouhaud sent in another revision of a patch to move query jumbling from
pg_stat_statements into core, expose queryid in pg_stat_activity and
log_line_prefix, and expose query identifier in EXPLAIN ... VERBOSE.

Bruce Momjian sent in a patch to fix up some GiST code comments.

Vik Fearing sent in another revision of a patch to implement GROUP BY DISTINCT,
which elides duplicated GROUPING SETs.

Mark Dilger sent in another revision of a patch to add a contrib extension,
pg_amcheck.

Pavel Borisov sent in another revision of a patch to make amcheck checking a
UNIQUE constraint for btree indexes.

Jacob Champion sent in another revision of a patch to add an API to the table AM
to accept a column projection list.

Joel Jacobson sent in two revisions of a patch to support empty ranges with
bounds information.

Tomáš Vondra sent in three more revisions of a patch to implement BRIN
multi-range indexes.

Peter Eisentraut sent in another revision of a patch to implement SQL-standard
function body.

Thomas Munro sent in two more revisions of a patch to implement parallel full
hash join.

Magnus Hagander sent in five revisions of a patch to add PROXY protocol support.

Vigneshwaran C sent in a patch to fix a Buildfarm failure in crake by separating
a declaration from an assignment in Perl code.

Michaël Paquier sent in another revision of a patch to enable the libcrypto
callbacks before checking whether SSL needs to be done.

Daniel Gustafsson sent in another revision of a patch to support NSS as a libpq
TLS backend.

Gilles Darold sent in a patch to implement regexp_count, regexp_instr,
regexp_substr and regexp_replace.

David Rowley sent in another revision of a patch to reduce the number of special
cases to build contrib modules on Windows.

Amit Langote sent in another revision of a patch to make UPDATE and DELETE scale
better on inheritance trees.

John Naylor sent in a patch to review some alternatives to the current popcount
implementations.

Mark Rofail sent in another revision of a patch to implement foreign key arrays.

Pavel Stěhule sent in three more revisions of a patch to make psql able to use a
pager for \watch.

Tom Lane sent in another revision of a patch to remove support for COPY FROM
STDIN in protocol version 2.

Mark Dilger sent in two revisions of a patch to add a pg_amcheck contrib
application.

Soumyadeep Chakraborty and Kyotaro HORIGUCHI traded patches to prevent the
checkpointer from writing to older timeline.

Amit Kapila sent in another revision of a patch to track replication origin
progress for rollbacks.

Masahiro Ikeda and Fujii Masao traded patches to add WAL write/fsync statistics
to pg_stat_wal.

Justin Pryzby and Takayuki Tsunakawa traded patches to speed up COPY FROM
on tables with foreign partitions.

Álvaro Herrera and Justin Pryzby traded patches to add batch/pipelining support
for libpq.

Daniel Gustafsson sent in three more revisions of a patch to disallow SSL
compression.

Andrey V. Lepikhov and Tom Lane traded patches to remove the 64K rangetable
limit.

Robins Tharakan sent in a patch to fix pg_upgrade for large numbers of large
objects.

Jacob Champion sent in a patch to rework the sslfiles Makefile target.

Kyotaro HORIGUCHI sent in another revision of a patch to move the callback call
from ReadPageInternal to XLogReadRecord, move the page reader out of
XLogReadRecord, remove globals readOff, readLen and readSegNo, and allow
xlogreader to use different xlog blocksizes.

Andy Fan sent in a patch to adjust the cost model for the partition pruning
case.

Kyotaro HORIGUCHI sent in another revision of a patch to make the
End-Of-Recovery error less scary.

Heikki Linnakangas sent in another revision of a patch to force lookahead in
COPY FROM parsing.

Daniel Gustafsson sent in another revision of a patch to remove deprecated
parameters authtype and pqtty from libpq.

Amul Sul sent in another revision of a patch to implement wal prohibit state
using a global barrier, and error or Assert before START_CRIT_SECTION for WAL
writes.

Thomas Munro sent in a patch to make relfile tombstone files conditional on WAL
level.

Amit Langote sent in another revision of a patch to make some cosmetic
improvements to the partition pruning step generation code.

Thomas Munro sent in another revision of a patch to replace buffer I/O locks
with condition variables.

Thomas Munro sent in two more revisions of a patch to add missing
pthread_barrier_t, refactor the way thread portability is done in pgbench,
improve pgbench's time measurement code, and synchronize its client threads.

Julien Rouhaud sent in another revision of a patch to fix various shared memory
estimates.

Laurenz Albe sent in two more revisions of a patch to improve \e, \ef and \ev if
the editor is quit without saving by retaining the current query buffer rather
than executing the previous query.

Masahiko Sawada sent in two revisions of a patch to ensure that
pg_stat_xxx_tables.n_mod_since_analyze is reset on TRUNCATE.

Tomáš Vondra sent in two more revisions of a patch to make it possible to
collect extended statistics on expressions.

Hayato Kuroda sent in another revision of a patch to refactor ECPGconnect and
allow IPv6 connections in same.

Kyotaro HORIGUCHI sent in another revision of a patch to delay checkpoint
completion after truncate success.

Kota Miyake sent in a patch to remove some warts from pgbench's \sleep
metacommand.

Hou Zhijie sent in a patch to avoid CCI in RI trigger when INSERTing an FK
relation.

Ibrar Ahmed sent in another revision of a patch to fix tests broken by an
earlier patch to make GROUP BY work more efficiently.

Kirk Jamison sent in another revision of a patch to implement tracing in libpq.

Kyotaro HORIGUCHI sent in another revision of a patch to change the stats
collector from using files for temporary storage to shared memory.

Andres Freund sent in another revision of a patch to ensure that on Windows,
PostgreSQL is only considered to be running as a service if stderr is invalid.

Thomas Munro sent in another revision of a patch to inject fault timing, and fix
a race condition in parallel hash join batch cleanup.

Andrew Dunstan sent in a patch to allow matching the whole DN from a client
certificate.

KaiGai Kohei and Tom Lane traded patches to add binary input/output handlers to
contrib/cube.

Bharath Rupireddy sent in two more revisions of a patch to refactor the code for
refreshing materialized views into a group of functions, and implement
EXPLAIN/EXPLAIN ANALYZE REFRESH MATERIALIZED VIEW.

Justin Pryzby sent in a patch to bootstrap that makes it possible to convert a
`Typ` to a `List*`, and use that to allow composite types in bootstrap.

Kyotaro HORIGUCHI sent in a patch to fix an intermittent failure in
011_crash_recovery.pl by adding a CHECKPOINT.

Joel Jacobson sent in a patch to create a pg_permissions view.

Joel Jacobson sent in a patch to create a pg_ownerships view.

Justin Pryzby sent in another revision of a patch to make it possible to run
CLUSTER on partitioned indexes.

Bharath Rupireddy sent in another revision of a patch to add another flavor of
pg_terminate_backend that allows people to specify wait and timeout.

Bharath Rupireddy sent in another revision of a patch to improve the "PID XXXX
is not a PostgreSQL server process" message by splitting out the case where
sending a signal is not allowed.

Li Japin sent in another revision of a patch to implement ALTER SUBSCRIPTION ...
ADD/DROP PUBLICATION.

Joe Conway sent in a patch to fix a bug in has_column_privilege()" that got
attnums and non-existent columns wrong.

Justin Pryzby sent in another revision of a patch to implement ALTER TABLE SET
ACCESS METHOD, allow specifying the table acccess method of partitioned tables
to be inherited by partitions, and implement lsyscache get_rel_relam() because
a table's AM is now in play.