Commit 924bcf4f introduced a framework
for parallel computation in PostgreSQL that makes most but not all
built-in functions safe to execute in parallel mode.  In order to have
parallel query, we'll need to be able to determine whether that query
contains functions (either built-in or user-defined) that cannot be
safely executed in parallel mode.  This requires those functions to be
labeled, so this patch introduces an infrastructure for that.  Some
functions currently labeled as safe may need to be revised depending on
how pending issues related to heavyweight locking under paralllelism
are resolved.

Parallel plans can't be used except for the case where the query will
run to completion.  If portal execution were suspended, the parallel
mode restrictions would need to remain in effect during that time, but
that might make other queries fail.  Therefore, this patch introduces
a framework that enables consideration of parallel plans only when it
is known that the plan will be run to completion.  This probably needs
some refinement; for example, at bind time, we do not know whether a
query run via the extended protocol will be execution to completion or
run with a limited fetch count.  Having the client indicate its
intentions at bind time would constitute a wire protocol break.  Some
contexts in which parallel mode would be safe are not adjusted by this
patch; the default is not to try parallel plans except from call sites
that have been updated to say that such plans are OK.

This commit doesn't introduce any parallel paths or plans; it just
provides a way to determine whether they could potentially be used.
I'm committing it on the theory that the remaining parallel sequential
scan patches will also get committed to this release, hopefully in the
not-too-distant future.

Robert Haas and Amit Kapila.  Reviewed (in earlier versions) by Noah
Misch.

Sync our regex code with upstream changes since last time we did this,
which was Tcl 8.5.11 (see commit 08fd6ff3).

The only functional change here is to disbelieve that an octal escape is
three digits long if it would exceed \377.  That's a bug fix, but it's
a minor one and could change the interpretation of working regexes, so
don't back-patch.

In addition to that, s/INFINITY/DUPINF/ to eliminate the risk of collisions
with <math.h>'s macro, and s/LOCAL/NOPROP/ because that also seems like
an unnecessarily collision-prone macro name.

There were some other cosmetic changes in their copy that I did not adopt,
notably a rather half-hearted attempt at renaming some of the C functions
in a more verbose style.  (I'm not necessarily against the concept, but
renaming just a few functions in the package is not an improvement.)

The docs claimed that \uhhhh would be interpreted as a Unicode value
regardless of the database encoding, but it's never been implemented
that way: \uhhhh and \xhhhh actually mean exactly the same thing, namely
the character that pg_mb2wchar translates to 0xhhhh.  Moreover we were
falsely dismissive of the usefulness of Unicode code points above FFFF.
Fix that.

It's been like this for ages, so back-patch to all supported branches.

Also, rewrite one error message to make it follow our message style
guidelines better.

Euler Taveira and Tom Lane

Oversight in commit 31eae602, which
replaced PrivGrantee nodes with RoleSpec nodes.  Spotted by Yugo Nagata.

This patch adds an option to replace the "time since pgbench run
started" with a Unix epoch timestamp in the progress report so that,
for instance, it is easier to compare timelines with pgsql log

Fabien COELHO <coelho@cri.ensmp.fr>

For the UPDATE/DELETE RETURNING case, filter the records which are not
visible to the user through ALL or SELECT policies from those considered
for the UPDATE or DELETE.  This is similar to how the GRANT system
works, which prevents RETURNING unless the caller has SELECT rights on
the relation.

Per discussion with Robert, Dean, Tom, and Kevin.

Back-patch to 9.5 where RLS was introduced.

This refactors rewrite/rowsecurity.c to simplify the handling of the
default deny case (reducing the number of places where we check for and
add the default deny policy from three to one) by splitting up the
retrival of the policies from the application of them.

This also allowed us to do away with the policy_id field.  A policy_name
field was added for WithCheckOption policies and is used in error
reporting, when available.

Patch by Dean Rasheed, with various mostly cosmetic changes by me.

Back-patch to 9.5 where RLS was introduced to avoid unnecessary
differences, since we're still in alpha, per discussion with Robert.

Commit 5ddc7288 does not actually work
because it will happily blow away ri_constraint_cache entries that are
in active use in outer call levels.  In any case, it's a very ugly,
brute-force solution to the problem of limiting the cache size.
Revert until it can be redesigned.

COMMENT supports POLICY but the documentation hadn't caught up with
that fact.

Patch by Charles Clavadetscher

Back-patch to 9.5 where POLICY was added.

Michael Paquier

This patch changes the log message which is logged when the server
successfully renames backup_label file to *.old but fails to rename
tablespace_map file during the shutdown. Previously the WARNING
message "online backup mode was not canceled" was logged in that case.
However this message is confusing because the backup mode is treated
as canceled whenever backup_label is successfully renamed. So this
commit makes the server log the message "online backup mode canceled"
in that case.

Also this commit changes errdetail messages so that they follow the
error message style guide.

Back-patch to 9.5 where tablespace_map file is introduced.

Original patch by Amit Kapila, heavily modified by me.

Per gripe from Robert Haas

Patch provides command line option --strict-names which requires that at
least one table/schema should present for each -t/-n option.

Pavel Stehule <pavel.stehule@gmail.com>

per gcc -Wsuggest-attribute=noreturn

To prevent perverse results, we now only return the other operand if
it's not scalar, and if both operands are of the same kind (array or
object).

Original bug complaint and patch from Oskari Saarenmaa, extended by me
to cover the cases of different kinds of jsonb.

Backpatch to 9.5 where jsonb_concat was introduced.

The web pages of Andy Dong at Berkeley don't exist anymore, and he is no
longer there.

WTIH -> WITH

Pointed out by Dmitriy Olshevskiy

Backpatch to 9.5 where create_policy.sgml was added.

Per buildfarm member crake.

Modify pg_dump to restore postgres/template1 databases to non-default
tablespaces by switching out of the database to be moved, then switching
back.

Also, to fix potentially cases where the old/new tablespaces might not
match, fix pg_upgrade to process new/old tablespaces separately in all
cases.

Report by Marti Raudsepp

Patch by Marti Raudsepp, me

Backpatch through 9.0

The previous way didn't work for vpath builds, and make distprep was
busted too.

Reported off-list by Andres Freund.

I think this particular branch is actually dead, but the analysis to
prove that is not trivial, so instead take the weasel way.

Reported by Jinyu Zhang
Backpatch to 9.5, where BRIN was introduced.

Commit 45ba424f improved foreign key lookups during bulk updates
when the FK value does not change.  When restoring a schema dump
from a database with many (say 100,000) foreign keys, this cache
would grow very big and every ALTER TABLE command was causing an
InvalidateConstraintCacheCallBack(), which uses a sequential hash
table scan.  This could cause a severe performance regression in
restoring a schema dump (including during pg_upgrade).

The patch uses a heuristic method of detecting when the hash table
should be destroyed and recreated.
InvalidateConstraintCacheCallBack() adds the current size of the
hash table to a counter.  When that sum reaches 1,000,000, the hash
table is flushed.  This fixes the regression without noticeable
harm to the bulk update use case.

Jan Wieck
Backpatch to 9.3 where the performance regression was introduced.

Naming the individual lwlocks seems like something that may be useful
for other types of debugging, monitoring, or instrumentation output,
but this commit just implements it for the specific case of
trace_lwlocks.

Patch by me, reviewed by Amit Kapila and Kyotaro Horiguchi

Back-patch to 9.3 where PageHeaderData layout was changed.

Michael Paquier

The "typo" alleged in commit 1e460d4b was actually a comment that was
correct when written, but I missed updating it in commit b5282aa8.
Use a slightly less specific (and hopefully more future-proof) description
of what is collected.  Back-patch to 9.2 where that commit appeared, and
revert the comment to its then-entirely-correct state before that.

We're adding OIDs, not TIDs, to invalItems.

Pointed out by Etsuro Fujita.

Back-patch to all supported branches.

The list-wrangling here was done wrong, allowing the same state to get
put into the list twice.  The following loop then would clone it twice.
The second clone would wind up with no inarcs, so that there was no
observable misbehavior AFAICT, but a useless state in the finished NFA
isn't an especially good thing.

Declaration of varibale inside ÓÝ×Õ

Mark index tuple as dead if it's pointed by kill_prior_tuple during
ordinary (search) scan and remove it during insert process if there is no
enough space for new tuple to insert. This improves select performance
because index will not return tuple marked as dead and improves insert
performance because it reduces number of page split.

Anastasia Lubennikova <a.lubennikova@postgrespro.ru> with
 minor editorialization by me

This commit makes postmaster forcibly remove the files signaling
a standby promotion request. Otherwise, the existence of those files
can trigger a promotion too early, whether a user wants that or not.

This removal of files is usually unnecessary because they can exist
only during a few moments during a standby promotion. However
there is a race condition: if pg_ctl promote is executed and creates
the files during a promotion, the files can stay around even after
the server is brought up to new master. Then, if new standby starts
by using the backup taken from that master, the files can exist
at the server startup and should be removed in order to avoid
an unexpected promotion.

Back-patch to 9.1 where promote signal file was introduced.

Problem reported by Feike Steenbergen.
Original patch by Michael Paquier, modified by me.

Discussion: 20150528100705.4686.91426@wrigleys.postgresql.org

Even views considered "simple" enough to be automatically updatable may
have mulitple relations involved (eg: in a where clause).  We need to
make sure and lock those relations when rewriting the query.

Back-patch to 9.3 where updatable views were added.

Pointed out by Andres, patch thanks to Dean Rasheed.

Author: Pavel Stehule
Reviewed-By: Andres Freund
Discussion: 5594FE7A.5050205@iki.fi

This was forgotten in 8a3631f8 (commit that originally added the parameter)
and 0ca9907c (commit that added the documentation later that year).

Back-patch to all supported versions.

Thomas Munro, reviewed by Michael Paquier, modified by me.

Per discussion, nowadays it is possible to have tablespaces that have
wildly different I/O characteristics from others.  Setting different
effective_io_concurrency parameters for those has been measured to
improve performance.

Author: Julien Rouhaud
Reviewed by: Andres Freund