Per gripe from Phil Bayer.

Authors: Amit Langote and others
Discussion: https://postgr.es/m/156236160709.1192.4498528196556144085@wrigleys.postgresql.org

This can cause valgrind to complain, as the flag marking a buffer as a
temporary copy was not getting initialized.

While on it, fill in with zeros newly-created buffer pages.  This does
not matter when loading a block from a temporary file, but it makes the
push of an index tuple into a new buffer page safer.

This has been introduced by 1d27dcf5, so backpatch all the way down to
9.4.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/15899-0d24fb273b3dd90c@postgresql.org
Backpatch-through: 9.4

This commit contains assorted fixes for jsonpath documentation including:
grammar fixes, incorrect examples fixes as well as wording improvements.

Discussion: https://postgr.es/m/CAA-aLv4VVX%3Db9RK5hkfPXJczqaiTdqO04teW9i0wiQVhdKcqzw%40mail.gmail.com
Author: Liudmila Mantrova
Reviewed-by: Alexander Korotkov
Reported-by: Thom Brown

86b85044 abstracted calls to heap functions in COPY FROM to support a
generic table AM.  However, when performing a copy into a partitioned
table, this commit neglected to call table_finish_bulk_insert for each
partition.  Before 86b85044, when we always called the heap functions,
there was no need to call heapam_finish_bulk_insert for partitions since
it only did any work when performing a copy without WAL.  For partitioned
tables, this was unsupported anyway, so there was no issue.  With
pluggable storage, we can't make any assumptions about what the table AM
might want to do in its equivalent function, so we'd better ensure we
always call table_finish_bulk_insert each partition that's received a row.

For now, we make the table_finish_bulk_insert call whenever we evict a
CopyMultiInsertBuffer out of the CopyMultiInsertInfo.  This does mean
that it's possible that we call table_finish_bulk_insert multiple times
per partition, which is not a problem other than being an inefficiency.
Improving this requires a more invasive patch, so let's leave that for
another day.

This also changes things so that we no longer needlessly call
table_finish_bulk_insert when performing a COPY FROM for a non-partitioned
table when not using multi-inserts.

Reported-by: Robert Haas
Backpatch-through: 12
Discussion: https://postgr.es/m/CA+TgmoYK=6BpxiJ0tN-p9wtH0BTAfbdxzHhwou0mdud4+BkYuQ@mail.gmail.com

Reported-by: Ashwin Agrawal
Author: Ashwin Agrawal
Reviewed-by: Amit Kapila
Backpatch-through: 12, where it was introduced
Discussion: https://postgr.es/m/CALfoeisgdZhYDrJOukaBzvXfJOK2FQ0szVMK7dzmcy6w93iDUA@mail.gmail.com

Otherwise the executor can't see trigger transition tables during
EPQ evaluation.  Fixes bug #15900 and almost certainly also #15720.
Back-patch to 10, where trigger transition tables landed.

Author: Alex Aktsipetrov
Reviewed-by: Thomas Munro, Tom Lane
Discussion: https://postgr.es/m/15900-bc482754fe8d7415%40postgresql.org
Discussion: https://postgr.es/m/15720-38c2b29e5d720187%40postgresql.org

We were creating the cloned triggers with an empty list of arguments,
losing the ones that had been specified by the user when creating the
trigger in the partitioned table.  Repair.

This was forgotten in commit 86f57594.

Author: Patrick McHardy
Reviewed-by: Tomas Vondra
Discussion: https://postgr.es/m/20190709130027.amr2cavjvo7rdvac@access1.trash.net
Discussion: https://postgr.es/m/15752-123bc90287986de4@postgresql.org

Otherwise the regressplans.sh tests generate extremely slow nested
loop joins.  Back-patch to 11 where the hash join tests came in.

Reported-by: Michael Paquier
Discussion: https://postgr.es/m/20190708055256.GB2709%40paquier.xyz

Discussion: https://postgr.es/m/20190706202425.GA16933@telsasoft.com

Author: Justin Pryzby

Backpatch-through: 12

Syntax is OpenSSL-specific, so only use it for OpenSSL.

Discussion: https://postgr.es/m/8232E273-7B25-47F4-B0E7-3D4264106F82@yesql.se

Author: Daniel Gustafsson

Backpatch-through: head

Remove quote_all_identifiers from struct _dumpOptions.

Discussion: https://postgr.es/m/d3d92ce9-78a4-8adb-0393-d3deeec29f7e@postgrespro.ru

Author: Arthur Zakirov

Backpatch-through: head

Most block-based table AMs will need the exact same implementation of
the relation_size callback as the heap, and if they use a standard
page layout, they will likely need an implementation of the
relation_estimate_size callback that is very similar to that of the
heap.  Rearrange to facilitate code reuse.

Patch by me, reviewed by Michael Paquier, Daniel Gustafsson, and
Álvaro Herrera.

Discussion: http://postgr.es/m/CA+TgmoZ6DBPnP1E-vRpQZUJQijJFD54F+SR_pxGiAAS-MyrigA@mail.gmail.com

Document that the data types of replicated tables do not need to
match.  The documentation previously claimed that they had to match.

Author: Robert Treat <rob@xzilla.net>
Discussion: https://www.postgresql.org/message-id/flat/CAJSLCQ13==D8Ka2YLyctTm0Y+8MhGYcX_zj7fU0rqRzhcV++3w@mail.gmail.com

This addresses a couple of issues in the code:
- Typos and inconsistencies in comments and function declarations.
- Removal of unreferenced function declarations.
- Removal of unnecessary compile flags.
- A cleanup error in regressplans.sh.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/0c991fdf-2670-1997-c027-772a420c4604@gmail.com

Use

    if (something() != 0)
        error ...

instead of just

    if (something)
        error ...

The latter is not incorrect, but it's a bit confusing and not the
common style.

Discussion: https://www.postgresql.org/message-id/flat/5de61b6b-8be9-7771-0048-860328efe027%402ndquadrant.com

Author: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoDuAYsRb3Q9aobkFZ6DZMWxsyg4HOmgkwgeWNfSkTwGxw@mail.gmail.com

This code failed to account for the possibility that malloc() would
change errno, resulting in wrong output for %m, not to mention the
possibility of message truncation.  Such a change is obviously
expected when malloc fails, but there's reason to fear that on some
platforms even a successful malloc call can modify errno.

Discussion: https://postgr.es/m/2576.1527382833@sss.pgh.pa.us

In normal interactive mode, psql's log messages accidentally got a
"psql:" prefix that was not supposed to be there.  This only happened
if there was no .psqlrc file being read, so it wasn't discovered for a
while.  Fix this by adding the appropriate logging format
configuration call in the right code path.

Discussion: https://www.postgresql.org/message-id/7586.1560540361@sss.pgh.pa.us

Reported-by: Ashwin Agrawal
Author: Ashwin Agrawal
Reviewed-by: Amit Kapila
Backpatch-through: 12, where it was introduced
Discussion: https://postgr.es/m/CALfoeisgdZhYDrJOukaBzvXfJOK2FQ0szVMK7dzmcy6w93iDUA@mail.gmail.com

I chanced to notice while thumbing through lcov reports that we had
exactly no coverage of BETWEEN SYMMETRIC, nor of current_time(N) and
localtime(N).  Improve that.

parse_expr.c still has a pretty awful coverage number, but a large part
of that is due to lack of coverage of the operator_precedence_warning
logic.  I have zero desire to write tests for that; I think ripping it
out would be more sensible at this point.

These seem to be leftovers from old patches, perhaps.

Masahiko Sawada

Discussion: https://postgr.es/m/CAD21AoDuAYsRb3Q9aobkFZ6DZMWxsyg4HOmgkwgeWNfSkTwGxw@mail.gmail.com

The code for conversions SQL_ASCII <-> MULE_INTERNAL and
SQL_ASCII <-> UTF8 was unreachable, because we long ago changed
the wrapper functions pg_do_encoding_conversion() et al so that
they have hard-wired behaviors for conversions involving SQL_ASCII.
(At least some of those fast paths date back to 2002, though it
looks like we may not have been totally consistent about this until
later.)  Given the lack of complaints, nobody is dissatisfied with
this state of affairs.  Hence, let's just remove the unreachable code.

Also, change CREATE CONVERSION so that it rejects attempts to
define such conversions.  Since we consider that SQL_ASCII represents
lack of knowledge about the encoding in use, such a conversion would
be semantically dubious even if it were reachable.

Adjust a couple of regression test cases that had randomly decided
to rely on these conversion functions rather than any other ones.

Discussion: https://postgr.es/m/41163.1559156593@sss.pgh.pa.us

The itemlen variable used to be referenced in multiple places, but since
reworking the serialization code it's used only in one assert. Fixed by
removing the variable and calling the macro from the assert directly.

Backpatch to 12, where this code was introduced.

Reported-by: Jeff Janes
Discussion: https://postgr.es/m/CAMkU=1zc_ovH9NZd_9ovuiEWkF9yX06URUDdXCmgDydf-bqB5A@mail.gmail.com

This is like \echo except that the text is sent to stderr not stdout.

In passing, fix a pre-existing bug in \echo and \qecho: per documentation
the -n switch should only be recognized when it is the first argument,
but actually any argument matching "-n" was treated as a switch.
(Should we back-patch that?)

David Fetter (bug fix by me), reviewed by Fabien Coelho

Discussion: https://postgr.es/m/20190421183115.GA4311@fetter.org

The Unix manual section that "man tcp" appears in varies, so let's
just leave it out of the command to run.

This is useful for monitoring, when it comes for example to calculations
of WAL retention with replication slots and delays with a set of
standbys.

Bump catalog version.

Author: Fabrízio de Royes Mello
Reviewed-by: Surafel Temesgen
Discussion: https://postgr.es/m/CAFcNs+oc8ZoHhowA4rR1GGCgG8QNgK_TOwPRVYQo5rYy8_PXzA@mail.gmail.com

The source defining the current fallback and hardcoded DH parameters
has disappeared from the web a long time ago, and RFC 3526 defines the
most current Diffie-Hellman MODP groups, so update to those new values.

Author: Daniel Gustafsson
Reviewed-by: Peter Eisentraut, Michael Paquier
Discussion: https://postgr.es/m/5E60AC9A-CB10-4851-9EF2-7209490A164C@yesql.se

The serialization format of multivariate MCV lists included alignment in
order to allow direct access to part of the serialized data, but despite
multiple fixes (see for example commits d85e0f36 and ea4e1c0e) this
proved to be problematic.

This commit abandons alignment in the serialized format, and just copies
everything during deserialization.  We now also track amount of memory
needed after deserialization (including alignment), which allows us to
deserialize the MCV list in a single pass.

Bump catversion, as this affects contents of pg_statistic_ext_data.

Backpatch to 12, where multi-column MCV lists were introduced.

Author: Tomas Vondra
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/2201.1561521148@sss.pgh.pa.us

The function pg_mcv_list_items() returns values stored in MCV items. The
items may contain columns with different data types, so the function was
generating text array-like representation, but in an ad-hoc way without
properly escaping various characters etc.

Fixed by simply building a text[] array, which also makes it easier to
use from queries etc.

Requires changes to pg_proc entry, so bump catversion.

Backpatch to 12, where multi-column MCV lists were introduced.

Author: Tomas Vondra
Reviewed-by: Dean Rasheed
Discussion: https://postgr.es/m/20190618205920.qtlzcu73whfpfqne@development

When building multi-column MCV lists, we compute base frequency for each
item, i.e. a product of per-column frequencies for values from the item.
As a value may be in multiple groups, the code was scanning the whole
array of groups while adding items to the MCV list.  This works fine as
long as the number of distinct groups is small, but it's easy to trigger
trigger O(N^2) behavior, especially after increasing statistics target.

This commit precomputes frequencies for values in all columns, so that
when computing the base frequency it's enough to make a simple bsearch
lookup in the array.

Backpatch to 12, where multi-column MCV lists were introduced.

Discussion: https://postgr.es/m/20190618205920.qtlzcu73whfpfqne@development

We can use the %zu format specifier directly, no need to cast to int.

Because there is no portable int64/uint64 format specifier and we
can't stick macros like INT64_FORMAT into the middle of a translatable
string, we have been using various workarounds that put the number to
be printed into a string buffer first.  Now that we always use our own
sprintf(), we can rely on %lld and %llu to work, so we can use those.

This patch undoes this workaround in a few places where it was
egregiously verbose.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/CAH2-Wz%3DWbNxc5ob5NJ9yqo2RMJ0q4HXDS30GVCobeCvC9A1L9A%40mail.gmail.com

The main change is a new stemmer for Greek.  There are minor changes
in the Danish and French stemmers.

Author: Panagiotis Mavrogiorgos <pmav99@gmail.com>

This is a follow-up refactoring after 09ec55b9 and b6742117, which has
proved that the encoding and decoding routines used by SCRAM have a
poor interface when it comes to check after buffer overflows.  This adds
an extra argument in the shape of the length of the result buffer for
each routine, which is used for overflow checks when encoding or
decoding an input string.  The original idea comes from Tom Lane.

As a result of that, the encoding routine can now fail, so all its
callers are adjusted to generate proper error messages in case of
problems.

On failure, the result buffer gets zeroed.

Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20190623132535.GB1628@paquier.xyz

The last set of scenarios did an initialization of nodes followed by an
extra command to set up the authentication policy with pg_regress
--config-auth.  This configuration step can be integrated directly using
the option auth_extra from PostgresNode::init when initializing the
node, saving from one extra command.  On Windows, this also restricts
more pg_ident.conf for the SSPI user mapping by removing the entry of
the OS user running the test, which is not needed anyway.

Note that IPC::Run mishandles double quotes, hence the restore user name
is changed to map with that.  This was already done in the test as a
later step, but not in a consistent way, causing the switch to use
auth_extra to fail.

Found while reviewing ca129e58.

Discussion: https://postgr.es/m/20190703062024.GD3084@paquier.xyz

This changes various places where appendPQExpBuffer was used in places
where it was possible to use appendPQExpBufferStr, and likewise for
appendStringInfo and appendStringInfoString.  This is really just a
stylistic improvement, but there are also small performance gains to be
had from doing this.

Discussion: http://postgr.es/m/CAKJS1f9P=M-3ULmPvr8iCno8yvfDViHibJjpriHU8+SXUgeZ=w@mail.gmail.com