Advancing a physical replication slot with pg_replication_slot_advance()
did not mark the slot as dirty if any advancing was done, preventing the
follow-up checkpoint to flush the slot data to disk. This caused the
advancing to be lost even on clean restarts. This does not happen for
logical slots as any advancing marked the slot as dirty. Per
discussion, the original feature has been implemented so as in the event
of a crash the slot may move backwards to a past LSN. This property is
kept and more documentation is added about that.
This commit adds some new TAP tests to check the persistency of physical
and logical slots after advancing across clean restarts.
Author: Alexey Kondratov, Michael Paquier
Reviewed-by: Andres Freund, Kyotaro Horiguchi, Craig Ringer
Discussion: https://postgr.es/m/059cc53a-8b14-653a-a24d-5f867503b0ee@postgrespro.ru
Backpatch-through: 11
Attempting to use CREATE INDEX, DROP INDEX or REINDEX with CONCURRENTLY
on a temporary relation with ON COMMIT actions triggered unexpected
errors because those operations use multiple transactions internally to
complete their work. Here is for example one confusing error when using
ON COMMIT DELETE ROWS:
ERROR: index "foo" already contains data
Issues related to temporary relations and concurrent indexing are fixed
in this commit by enforcing the non-concurrent path to be taken for
temporary relations even if using CONCURRENTLY, transparently to the
user. Using a non-concurrent path does not matter in practice as locks
cannot be taken on a temporary relation by a session different than the
one owning the relation, and the non-concurrent operation is more
effective.
The problem exists with REINDEX since v12 with the introduction of
CONCURRENTLY, and with CREATE/DROP INDEX since CONCURRENTLY exists for
those commands. In all supported versions, this caused only confusing
error messages to be generated. Note that with REINDEX, it was also
possible to issue a REINDEX CONCURRENTLY for a temporary relation owned
by a different session, leading to a server crash.
The idea to enforce transparently the non-concurrent code path for
temporary relations comes originally from Andres Freund.
Reported-by: Manuel Rigger
Author: Michael Paquier, Heikki Linnakangas
Reviewed-by: Andres Freund, Álvaro Herrera, Heikki Linnakangas
Discussion: https://postgr.es/m/CA+u7OA6gP7YAeCguyseusYcc=uR8+ypjCcgDDCTzjQ+k6S9ksQ@mail.gmail.com
Backpatch-through: 9.4
We realized years ago that it's better for libpq to accept all
connection parameters syntactically, even if some are ignored or
restricted due to lack of the feature in a particular build.
However, that lesson from the SSL support was for some reason never
applied to the GSSAPI support. This is causing various buildfarm
members to have problems with a test case added by commit 6136e94dc,
and it's just a bad idea from a user-experience standpoint anyway,
so fix it.
While at it, fix some places where parameter-related infrastructure
was added with the aid of a dartboard, or perhaps with the aid of
the anti-pattern "add new stuff at the end". It should be safe
to rearrange the contents of struct pg_conn even in released
branches, since that's private to libpq (and we'd have to move
some fields in some builds to fix this, anyway).
Back-patch to all supported branches.
Discussion: https://postgr.es/m/11297.1576868677@sss.pgh.pa.us
The "auth-methods" <sect1> used to include descriptions of all our
authentication methods. Commit 56811e573 promoted its child <sect2>'s
to <sect1>'s, which has advantages but also created some issues:
* The auth-methods page itself is essentially empty/useless.
* Links that pointed to "auth-methods" as a placeholder for all
auth methods were rendered a bit nonsensical.
* DocBook no longer provides a subsection table-of-contents here,
which formerly was a useful if terse summary of available auth methods.
To improve matters, add a handwritten list of all the auth methods.
Per gripe from Dave Cramer. Back-patch to v11 where the previous
commit came in.
Discussion: https://postgr.es/m/CADK3HH+xQLhcPgg=kWqfogtXGGZr-JdSo=x=WQC0PkAVyxUWyQ@mail.gmail.com
Back-patch commits 36d442a25 and 1f66c657f into all supported
branches. I'd considered doing this when putting in the latter
commit, but failed to pull the trigger. Now that we've had an
actual field complaint about the lack of such docs, let's do it.
Per bug #16158 from Piotr Jander. Original patches by Lætitia Avrot,
Patrick Francelle, and me.
Discussion: https://postgr.es/m/16158-7ccf2f74b3d655db@postgresql.org
Commit 5770172cb0 wrote, incorrectly, that
certain schema usage patterns are secure against CREATEROLE users and
database owners. When an untrusted user is the database owner or holds
CREATEROLE privilege, a query is secure only if its session started with
SELECT pg_catalog.set_config('search_path', '', false) or equivalent.
Back-patch to 9.4 (all supported versions).
Discussion: https://postgr.es/m/20191013013512.GC4131753@rfd.leadboat.com
The existing text stated that "Default privileges that are specified
per-schema are added to whatever the global default privileges are for
the particular object type". However, that bare-bones observation is
not quite clear enough, as demonstrated by the complaint in bug #16124.
Flesh it out by stating explicitly that you can't revoke built-in
default privileges this way, and by providing an example to drive
the point home.
Back-patch to all supported branches, since it's been like this
from the beginning.
Discussion: https://postgr.es/m/16124-423d8ee4358421bc@postgresql.org
Commit 6b76f1bb5 changed all the RADIUS auth parameters to be lists
rather than single values. But its use of SplitIdentifierString
to parse the list format was not very carefully thought through,
because that function thinks it's parsing SQL identifiers, which
means it will (a) downcase the strings and (b) truncate them to
be shorter than NAMEDATALEN. While downcasing should be harmless
for the server names and ports, it's just wrong for the shared
secrets, and probably for the NAS Identifier strings as well.
The truncation aspect is at least potentially a problem too,
though typical values for these parameters would fit in 63 bytes.
Fortunately, we now have a function SplitGUCList that is exactly
the same except for not doing the two unwanted things, so fixing
this is a trivial matter of calling that function instead.
While here, improve the documentation to show how to double-quote
the parameter values. I failed to resist the temptation to do
some copy-editing as well.
Report and patch from Marcos David (bug #16106); doc changes by me.
Back-patch to v10 where the aforesaid commit came in, since this is
arguably a regression from our previous behavior with RADIUS auth.
Discussion: https://postgr.es/m/16106-7d319e4295d08e70@postgresql.org
The example of expansion of multiple views claimed that the resulting
subquery nest would not get fully flattened because of an aggregate
function. There's no aggregate in the example, though, only a user
defined function confusingly named MIN(). In a modern server, the
reason for the non-flattening is that MIN() is volatile, but I'm
unsure whether that was true back when this text was written.
Let's reduce the confusion level by using LEAST() instead (which
we didn't have at the time this example was created). And then
we can just say that the planner will flatten the sub-queries, so
the rewrite system doesn't have to.
Noted by Paul Jungwirth. This text is old enough to vote, so
back-patch to all supported branches.
Discussion: https://postgr.es/m/CA+renyXZFnmp9PcvX1EVR2dR=XG5e6E-AELr8AHCNZ8RYrpnPw@mail.gmail.com
The previous statement that using a passphrase disables the ability to
change the server's SSL configuration without a server restart was no
longer completely true since the introduction of
ssl_passphrase_command_supports_reload.
Currently, postgres_fdw does not support preparing a remote transaction
for two-phase commit even in the case where the remote transaction is
read-only, but the old error message appeared to imply that that was not
supported only if the remote transaction modified remote tables. Change
the message so as to include the case where the remote transaction is
read-only.
Also fix a comment above the message.
Also add a note about the lack of supporting PREPARE TRANSACTION to the
postgres_fdw documentation.
Reported-by: Gilles Darold
Author: Gilles Darold and Etsuro Fujita
Reviewed-by: Michael Paquier and Kyotaro Horiguchi
Backpatch-through: 9.4
Discussion: https://postgr.es/m/08600ed3-3084-be70-65ba-279ab19618a5%40darold.net
Starting with PostgreSQL 12, pg_restore refuses to run when neither -d
nor -f are specified (c.f. commit 413ccaa74d), and it also makes "-f -"
mean the old implicit behavior of dumping to stdout. However, older
branches write to a file called ./- when invoked like that, making it
impossible to write pg_restore scripts that work across versions. This
is a partial backpatch of the aforementioned commit to all older
supported branches, providing an upgrade path.
Discussion: https://postgr.es/m/20191006190839.GE18030@telsasoft.com
This clarifies more how to use and how to take advantage of constraints
when attaching a new partition.
Author: Justin Pryzby
Reviewed-by: Amit Langote, Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/20191028001207.GB23808@telsasoft.com
Backpatch-through: 10
This fixes multiple areas of the documentation:
- COPY for its past compatibility section.
- SET ROLE mentioning INHERITS instead of INHERIT
- PREPARE referring to stmt_name, that is not present.
- Extension documentation about format name with upgrade scripts.
Backpatch down to 9.4 for the relevant parts.
Author: Alexander Lakhin
Discussion: https://postgr.es/m/bf95233a-9943-b341-e2ff-a860c28af481@gmail.com
Backpatch-through: 9.4
The array <@ and @> operators do not worry about duplicates: if every
member of array X matches some element of array Y, then X is contained
in Y, even if several members of X get matched to the same Y member.
This was not explicitly stated in the docs though, so improve matters.
Discussion: https://postgr.es/m/156614120484.1310.310161642239149585@wrigleys.postgresql.org
The entry for commit f24649976 claimed that citext_pattern_ops could be
used for LIKE index searches, but in fact it cannot. That patch only
created the opclass and some related operators, without doing anything
to teach the planner about how to use it. The opclass is basically
useless in this unfinished state, which is why nothing was added to the
main documentation about it, and really we shouldn't have said anything
in the release notes either. So remove the entry.
Discussion: https://postgr.es/m/CAKqncch4eBt2c8ddNVxzcVh3fFhdk54QoDMzpKgpqor4gA-wcQ@mail.gmail.com
It's important users be able to know (without looking at the source code)
that running DDL or DDL-like commands can interrupt autovacuum which can
lead to a lot of dead tuples and hence slower database operations.
Reported-by: James Coleman
Author: James Coleman
Reviewed-by: Amit Kapila
Backpatch-through: 9.4
Discussion: https://postgr.es/m/CAAaqYe-XYyNwML1=f=gnd0qWg46PnvD=BDrCZ5-L94B887XVxQ@mail.gmail.com
1. Commit 7086be6e3 should have documented the limitation that the direct
modification is disabled when WCO constraints are present, but didn't,
which is definitely my fault. Update the documentation (Postgres 9.6
onwards).
2. Commit fc22b6623 should have documented the limitation that the direct
modification is disabled when generated columns are defined, but
didn't. Update the documentation (Postgres 12 onwards).
Author: Etsuro Fujita
Discussion: https://postgr.es/m/CAPmGK14AYCPunLb6TRz1CQsW5Le01Z2ox8LSOKH0P-cOVDcQRA%40mail.gmail.com
The example used to explain 'Looping Through Query Results' uses
pseudo-materialized views. Replace it with a more up-to-date example
which does the same thing with actual materialized views, which have
been available since PostgreSQL 9.3.
In the passing, change '%' as format specifier instead of '%s' as is used
in other examples in plpgsql.sgml.
Reported-by: Ian Barwick
Author: Ian Barwick
Reviewed-by: Amit Kapila
Backpatch-through: 9.4
Discussion: https://postgr.es/m/9a70d393-7904-4918-c97c-649f6d114b6a@2ndquadrant.com
Give it an explanatory para like the other default roles have.
Don't imply that it can send any signal whatever.
In passing, reorder the table entries and explanatory paras
for the default roles into some semblance of consistency.
Ian Barwick, tweaked a bit by me.
Discussion: https://postgr.es/m/89907e32-76f3-7282-a89c-ea19c722fe5d@2ndquadrant.com
Section 4.2.7 says that unless otherwise specified, built-in
aggregates ignore rows in which any input is null. This is
not true of the JSON aggregates, but it wasn't documented.
Fix that.
Of the other entries in table 9.55, some were explicit about
ignoring nulls, and some weren't; for consistency and
self-contained-ness, make them all say it explicitly.
Per bug #15884 from Tim Möhlmann. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/15884-c32d848f787fcae3@postgresql.org
This adds a section for heap-related functions. These were previously
mixed with functions having a more general purpose, leading to
confusion. While on it, add a query example for fsm_page_contents.
Backpatch down to 10, where b5e3942 introduced the subsections for
function types in pageinspect documentation.
Author: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoDyM7E1+cK3-aWejxKTGC-wVVP2B+RnJhN6inXyeRmqzw@mail.gmail.com
Backpatch-through: 10
VACUUM's reference page had this text, but ANALYZE's didn't. That's
a clear oversight given that section 5.7 explicitly delegates the
responsibility to define permissions requirements to the individual
commands' man pages.
Per gripe from Isaac Morland. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAMsGm5fp3oBUs-2iRfii0iEO=fZuJALVyM2zJLhNTjG34gpAVQ@mail.gmail.com
Commit aa27977fe2 introduced this
restriction for pg_temp.function_name(arg); do likewise for types
created in temporary schemas. Programs that this breaks should add
"pg_temp." schema qualification or switch to arg::type_name syntax.
Back-patch to 9.4 (all supported versions).
Reviewed by Tom Lane. Reported by Tom Lane.
Security: CVE-2019-10208
The table has not been updated for some commands introduced in recent
releases, so refresh it. While on it, reorder entries alphabetically.
Backpatch all the way down for all the commands which have gone
missing.
Reported-by: Jeremy Smith
Discussion: https://postgr.es/m/15883-afff0ea3cc2dbbb6@postgresql.org
Backpatch-through: 9.4
Using pg_receivewal with synchronous_commit = remote_apply set in the
backend is incompatible if pg_receivewal is a synchronous standby as it
never applies WAL, so document this problem and solutions to it.
Backpatch to 9.6, where remote_apply has been added.
Author: Robert Haas, Jesper Pedersen
Reviewed-by: Laurenz Albe, Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/1427a2d3-1e51-9335-1931-4f8853d90d5e@redhat.com
Backpatch-through: 9.6
16828d5 has improved ALTER TABLE so as a column addition does not
require a rewrite for a non-NULL default with constant expressions, but
one spot in the documentation did not get updated consistently.
The documentation also now clarifies the fact that this does not apply
if the expression is volatile, where a table rewrite is still required.
Reported-by: Daniel Westermann
Author: Ian Barwick
Reviewed-by: Michael Paquier, Daniel Westermann
Discussion: https://postgr.es/m/DB6PR0902MB2184C7D5645CF15D75EB7957D2CF0@DB6PR0902MB2184.eurprd09.prod.outlook.com
Backpatch-through: 11
When a partitioned tables contains foreign tables as partitions, it is
not possible to implement unique or primary key indexes -- but when
regular indexes are created, there is no reason to do anything other
than ignoring such partitions. We were raising errors upon encountering
the foreign partitions, which is unfriendly and doesn't protect against
any actual problems.
Relax this restriction so that index creation is allowed on partitioned
tables containing foreign partitions, becoming a no-op on them. (We may
later want to redefine this so that the FDW is told to create the
indexes on the foreign side.) This applies to CREATE INDEX, as well as
ALTER TABLE / ATTACH PARTITION and CREATE TABLE / PARTITION OF.
Backpatch to 11, where indexes on partitioned tables were introduced.
Discussion: https://postgr.es/m/15724-d5a58fa9472eef4f@postgresql.org
Author: Álvaro Herrera
Reviewed-by: Amit Langote
datatype.sgml failed to explain that boolin() accepts any unique
prefix of the basic input strings. Indeed it was actively misleading
because it called out a few minimal prefixes without mentioning that
there were more valid inputs.
I also felt that it wasn't doing anybody any favors by conflating
SQL key words, valid Boolean input, and string literals containing
valid Boolean input. Rewrite in hopes of reducing the confusion.
Per bug #15836 from Yuming Wang, as diagnosed by David Johnston.
Back-patch to supported branches.
Discussion: https://postgr.es/m/15836-656fab055735f511@postgresql.org
A few questionable partitioning designs have been cropping up lately
around the mailing lists. Generally, these cases have been partitioning
using too many partitions which have caused performance or OOM problems for
the users.
Since we have very little else to guide users into good design, here we
add a new section to the partitioning documentation with some best
practise guidelines for good design.
Reviewed-by: Justin Pryzby, Amit Langote, Alvaro Herrera
Discussion: https://postgr.es/m/CAKJS1f-2rx+E9mG3xrCVHupefMjAp1+tpczQa9SEOZWyU7fjEA@mail.gmail.com
Backpatch-through: 10
json_to_record(), when an output column is declared as type json or jsonb,
should emit the corresponding field of the input JSON object. But it got
this slightly wrong when the field is just a string literal: it failed to
escape the contents of the string. That typically resulted in syntax
errors if the string contained any double quotes or backslashes.
jsonb_to_record() handles such cases correctly, but I added corresponding
test cases for it too, to prevent future backsliding.
Improve the documentation, as it provided only a very hand-wavy
description of the conversion rules used by these functions.
Per bug report from Robert Vollmert. Back-patch to v10 where the
error was introduced (by commit cf35346e8).
Note that PG 9.4 - 9.6 also get this case wrong, but differently so:
they feed the de-escaped contents of the string literal to json[b]_in.
That behavior is less obviously wrong, so possibly it's being depended on
in the field, so I won't risk trying to make the older branches behave
like the newer ones.
Discussion: https://postgr.es/m/D6921B37-BD8E-4664-8D5F-DB3525765DCD@vllmrt.net
Continuous operation cannot be achieved without applying this technique,
so it needs to be properly described.
Author: Álvaro Herrera
Reported-by: Tom Lane
Discussion: https://postgr.es/m/8756.1556302759@sss.pgh.pa.us
Support of CHECK OPTION for updatable views has been added in 9.4, but
the documentation of information_schema never got the call even if the
information displayed is correct.
Author: Gilles Darold
Discussion: https://postgr.es/m/75d07704-6c74-4f26-656a-10045c01a17e@darold.net
Backpatch-through: 9.4
An upcoming HEAD-only patch will standardize the terminology around
ItemIdData variables/line pointers, ending the practice of referring to
them as "item pointers". Make the "Database Page Layout" docs
consistent with the new policy. The term "item identifier" is already
used in the same section, so stick with that.
Discussion: https://postgr.es/m/CAH2-Wz=c=MZQjUzde3o9+2PLAPuHTpVZPPdYxN=E4ndQ2--8ew@mail.gmail.com
Backpatch: All supported branches.
Previously it's documented that use of replication functions is
restricted to superusers. This is true for the functions which
use replication origin, but not for pg_logicl_emit_message() and
functions which use replication slot. For example, not only
superusers but also users with REPLICATION privilege is allowed
to use the functions for replication slot. This commit fixes
the documentation for the privileges required for those replication
functions.
Back-patch to 9.4 (all supported versions).
Author: Matsumura Ryo
Discussion: https://postgr.es/m/03040DFF97E6E54E88D3BFEE5F5480F74ABA6E16@G01JPEXMBYT04
The interaction of these parameters was a bit confused/confusing,
and in fact v11 entirely misses the opportunity to apply partition
constraints when a partition is accessed directly (rather than
indirectly from its parent).
In HEAD, establish the principle that enable_partition_pruning controls
partition pruning and nothing else. When accessing a partition via its
parent, we do partition pruning (if enabled by enable_partition_pruning)
and then there is no need to consider partition constraints in the
constraint_exclusion logic. When accessing a partition directly, its
partition constraints are applied by the constraint_exclusion logic,
only if constraint_exclusion = on.
In v11, we can't have such a clean division of these GUCs' effects,
partly because we don't want to break compatibility too much in a
released branch, and partly because the clean coding requires
inheritance_planner to have applied partition pruning to a partitioned
target table, which it doesn't in v11. However, we can tweak things
enough to cover the missed case, which seems like a good idea since
it's potentially a performance regression from v10. This patch keeps
v11's previous behavior in which enable_partition_pruning overrides
constraint_exclusion for an inherited target table, though.
In HEAD, also teach relation_excluded_by_constraints that it's okay to use
inheritable constraints when trying to prune a traditional inheritance
tree. This might not be thought worthy of effort given that that feature
is semi-deprecated now, but we have enough infrastructure that it only
takes a couple more lines of code to do it correctly.
Amit Langote and Tom Lane
Discussion: https://postgr.es/m/9813f079-f16b-61c8-9ab7-4363cab28d80@lab.ntt.co.jp
Discussion: https://postgr.es/m/29069.1555970894@sss.pgh.pa.us
Commit 3d956d9562 added support for update row movement in postgres_fdw.
This patch fixes the following issues introduced by that commit:
* When a remote partition chosen to insert routed rows into was also an
UPDATE subplan target rel that would be updated later, the UPDATE that
used a direct modification plan modified those routed rows incorrectly
because those routed rows were visible to the later UPDATE command.
The right fix for this would be to have some way in postgres_fdw in
which the later UPDATE command ignores those routed rows, but it seems
hard to do so with the current infrastructure. For now throw an error
in that case.
* When a remote partition chosen to insert routed rows into was also an
UPDATE subplan target rel, fmstate created for the UPDATE that used a
non-direct modification plan was mistakenly overridden by another
fmstate created for inserting those routed rows into the partition.
This caused 1) server crash when the partition would be updated later,
and 2) resource leak when the partition had been already updated. To
avoid that, adjust the treatment of the fmstate for the inserting. As
for #1, since we would also have the incorrectness issue as mentioned
above, error out in that case as well.
Update the docs to mention that postgres_fdw currently does not handle
the case where a remote partition chosen to insert a routed row into is
also an UPDATE subplan target rel that will be updated later.
Author: Amit Langote and Etsuro Fujita
Reviewed-by: Amit Langote
Backpatch-through: 11 where row movement in postgres_fdw was added
Discussion: https://postgr.es/m/21e7eaa4-0d4d-20c2-a1f7-c7e96f4ce440@lab.ntt.co.jp
This commit adds the description that "non-exclusive" pg_start_backup
and pg_stop_backup can be executed even during recovery. Previously
it was wrongly documented that those functions are not allowed to be
executed during recovery.
Back-patch to 9.6 where non-exclusive backup API was added.
Discussion: https://postgr.es/m/CAHGQGwEuAYrEX7Yhmf2MCrTK81HDkkg-JqsOUh8zw6+zYC5zzw@mail.gmail.com
The limitations that it is not allowed to create/attach a foreign table
as a partition of an indexed partitioned table were not documented.
Reported-By: Stepan Yankevych
Author: Etsuro Fujita
Reviewed-By: Amit Langote
Backpatch-through: 11 where partitioned index was introduced
Discussion: https://postgr.es/m/1553869152.858391073.5f8m3n0x@frv53.fwdcdn.com
Since 11, it is possible to use a non-superuser role when using an
online source cluster with pg_rewind as long as the role has proper
permissions to execute on the source all the functions used by
pg_rewind, and the documentation stated that a superuser is necessary.
Let's add at the same time all the details needed to create such a
role.
A second confusion which comes a lot from users is that it is necessary
to issue a checkpoint on a freshly-promoted standby so as its control
file has up-to-date timeline information which is used by pg_rewind to
validate the operation. Let's document that properly. This is
back-patched down to 9.5 where pg_rewind has been introduced.
Author: Michael Paquier
Reviewed-by: Magnus Hagander
Discussion: https://postgr.es/m/CABUevEz5bpvbwVsYCaSMV80CBZ5-82nkMzbb+Bu=h1m=rLdn=g@mail.gmail.com
Backpatch-through: 9.5
Previously we were using the SQL:2003 definition, which doesn't allow
this, but that creates a serious dump/restore gotcha: there is no
setting of xmloption that will allow all valid XML data. Hence,
switch to the 2006 definition.
Since libxml doesn't accept <!DOCTYPE> directives in the mode we
use for CONTENT parsing, the implementation is to detect <!DOCTYPE>
in the input and switch to DOCUMENT parsing mode. This should not
cost much, because <!DOCTYPE> should be close to the front of the
input if it's there at all. It's possible that this causes the
error messages for malformed input to be slightly different than
they were before, if said input includes <!DOCTYPE>; but that does
not seem like a big problem.
In passing, buy back a few cycles in parsing of large XML documents
by not doing strlen() of the whole input in parse_xml_decl().
Back-patch because dump/restore failures are not nice. This change
shouldn't break any cases that worked before, so it seems safe to
back-patch.
Chapman Flack (revised a bit by me)
Discussion: https://postgr.es/m/CAN-V+g-6JqUQEQZ55Q3toXEN6d5Ez5uvzL4VR+8KtvJKj31taw@mail.gmail.com
1. The PARTITION OF clause of CREATE FOREIGN TABLE was not explained in
the CREATE FOREIGN TABLE reference page. Add it.
(Postgres 10 onwards)
2. The limitation that tuple routing cannot target partitions that are
foreign tables was not documented clearly enough. Improve wording.
(Postgres 10 onwards)
3. The UPDATE tuple re-routing concurrency behavior was explained in
the DDL chapter, which doesn't seem the right place. Move it to the
UPDATE reference page instead. (Postgres 11 onwards).
Authors: Amit Langote, David Rowley.
Reviewed-by: Etsuro Fujita.
Reported-by: Derek Hans
Discussion: https://postgr.es/m/CAGrP7a3Xc1Qy_B2WJcgAD8uQTS_NDcJn06O5mtS_Ne1nYhBsyw@mail.gmail.com
Reflecting an updated parameter value requires a server restart, which
was not mentioned in the documentation and in postgresql.conf.sample.
Reported-by: Thomas Poty
Discussion: https://postgr.es/m/15659-0cd812f13027a2d8@postgresql.org
In previous releases, the input file of dbtoepub was postgres.xml, and
dbtoepub knows to derive the output file name postgres.epub from that
automatically. But now the intput file is postgres.sgml (since
postgres.sgml is itself an XML file and we no longer need the
intermediate postgres.xml file), but dbtoepub doesn't know how to deal
with the .sgml suffix, so the automatically derived output file name
becomes postgres.sgml.epub. Fix by adding an explicit -o option.
The dblink documentation claims that an empty string is returned if there
has been no error, however OK is actually returned in that case. Also,
clarify that an async error may not be seen unless dblink_is_busy() or
dblink_get_result() have been called first.
Backpatch to all supported branches.
Reported-by: realyota
Backpatch-through: 9.4
Discussion: https://postgr.es/m/153371978486.1298.2091761143788088262@wrigleys.postgresql.org
The current wording can confuse the reader about constraint exclusion
being available at query execution, but this only applies to partition
pruning.
Reported-by: Shouyu Luo
Author: David Rowley
Reviewed-by: Chapman Flack, Amit Langote
Discussion: https://postgr.es/m/15629-2ef8b22e61f8333f@postgresql.org
The previous ordering of these steps satisfied the nominal requirement
that set_rel_pathlist_hook could editorialize on the whole set of Paths
constructed for a base relation. In practice, though, trying to change
the set of partial paths was impossible. Adding one didn't work because
(a) it was too late to be included in Gather paths made by the core code,
and (b) calling add_partial_path after generate_gather_paths is unsafe,
because it might try to delete a path it thinks is dominated, but that
is already embedded in some Gather path(s). Nor could the hook safely
remove partial paths, for the same reason that they might already be
embedded in Gathers.
Better to call extensions first, let them add partial paths as desired,
and then gather. In v11 and up, we already doubled down on that ordering
by postponing gathering even further for single-relation queries; so even
if the hook wished to editorialize on Gather path construction, it could
not.
Report and patch by KaiGai Kohei. Back-patch to 9.6 where Gather paths
were added.
Discussion: https://postgr.es/m/CAOP8fzahwpKJRTVVTqo2AE=mDTz_efVzV6Get_0=U3SO+-ha1A@mail.gmail.com
In commit f16241bef7, we have changed the behavior for concurrent updates
that move row to a different partition, but forgot to update the docs.
Previously when an UPDATE command causes a row to move from one partition
to another, there is a chance that another concurrent UPDATE or DELETE
misses this row. However, now we raise a serialization failure error in
such a case.
Reported-by: David Rowley
Author: David Rowley and Amit Kapila
Backpatch-through: 11 where it was introduced
Discussion: https://postgr.es/m/CAKJS1f-iVhGD4-givQWpSROaYvO3c730W8yoRMTF9Gc3craY3w@mail.gmail.com
Historically we've had each release branch include all prior branches'
notes, including minor-release changes, back to the beginning of the
project. That's basically an O(N^2) proposition, and it was starting to
catch up with us: as of HEAD the back-branch release notes alone accounted
for nearly 30% of the documentation. While there's certainly some value
in easy access to back-branch notes, this is getting out of hand.
Hence, switch over to the rule that each branch contains only its own
release notes. So as to not make older notes too hard to find, each
branch will provide URLs for the immediately preceding branches'
release notes on the project website.
There might be value in providing aggregated notes across all branches
somewhere on the website, but that's a task for another day.
Discussion: https://postgr.es/m/cbd4aeb5-2d9c-8b84-e968-9e09393d4c83@postgresql.org
Add PG_CFLAGS, PG_CXXFLAGS, and PG_LDFLAGS variables to pgxs.mk which
will be appended or prepended to the corresponding make variables.
Notably, there was previously no way to pass custom CXXFLAGS to third
party extension module builds, COPT and PROFILE supporting only CFLAGS
and LDFLAGS.
Backpatch all the way down to ease integration with existing
extensions.
Author: Christoph Berg
Reviewed-by: Andres Freund, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20181113104005.GA32154@msg.credativ.de
Backpatch-through: 9.4
Previously, \g would successfully execute the COPY command, but
the target specification if any was ignored, so that the data was
always dumped to the regular query output target. This seems like
a clear bug, so let's not just fix it but back-patch it.
While at it, adjust the documentation for \copy to recommend
"COPY ... TO STDOUT \g foo" as a plausible alternative.
Back-patch to 9.5. The problem exists much further back, but the
code associated with \g was refactored enough in 9.5 that we'd
need a significantly different patch for 9.4, and it doesn't
seem worth the trouble.
Daniel Vérité, reviewed by Fabien Coelho
Discussion: https://postgr.es/m/15dadc39-e050-4d46-956b-dcc4ed098753@manitou-mail.org
Since LISTEN is (still) disallowed, UNLISTEN must be a no-op in a
hot-standby session, and so there's no harm in allowing it. This
change allows client code to not worry about whether it's connected
to a primary or standby server when performing session-state-reset
type activities. (Note that DISCARD ALL, which includes UNLISTEN,
was already allowed, making it inconsistent to reject UNLISTEN.)
Per discussion, back-patch to all supported versions.
Shay Rojansky, reviewed by Mi Tar
Discussion: https://postgr.es/m/CADT4RqCf2gA_TJtPAjnGzkC3ZiexfBZiLmA-mV66e4UyuVv8bA@mail.gmail.com
The pgbench regression test supposed that srandom() with a specific value
would result in deterministic output from random(), as required by POSIX.
It emerges however that OpenBSD is too smart to be constrained by mere
standards, so their random() emits nondeterministic output anyway.
While a workaround does exist, what seems like a better fix is to stop
relying on the platform's srandom()/random() altogether, so that what
you get from --random-seed=N is not merely deterministic but platform
independent. Hence, use a separate pg_jrand48() random sequence in
place of random().
Also adjust the regression test case that's supposed to detect
nondeterminism so that it's more likely to detect it; the original
choice of random_zipfian parameter tended to produce the same output
all the time even if the underlying behavior wasn't deterministic.
In passing, improve pgbench's docs about random_zipfian().
Back-patch to v11 where this code was introduced.
Fabien Coelho and Tom Lane
Discussion: https://postgr.es/m/4615.1547792324@sss.pgh.pa.us
Attempting to use a temporary table within a two-phase transaction is
forbidden for ages. However, there have been uncovered grounds for
a couple of other object types and commands which work on temporary
objects with two-phase commit. In short, trying to create, lock or drop
an object on a temporary schema should not be authorized within a
two-phase transaction, as it would cause its state to create
dependencies with other sessions, causing all sorts of side effects with
the existing session or other sessions spawned later on trying to use
the same temporary schema name.
Regression tests are added to cover all the grounds found, the original
report mentioned function creation, but monitoring closer there are many
other patterns with LOCK, DROP or CREATE EXTENSION which are involved.
One of the symptoms resulting in combining both is that the session
which used the temporary schema is not able to shut down completely,
waiting for being able to drop the temporary schema, something that it
cannot complete because of the two-phase transaction involved with
temporary objects. In this case the client is able to disconnect but
the session remains alive on the backend-side, potentially blocking
connection backend slots from being used. Other problems reported could
also involve server crashes.
This is back-patched down to v10, which is where 9b013dc has introduced
MyXactFlags, something that this patch relies on.
Reported-by: Alexey Bashtanov
Author: Michael Paquier
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/5d910e2e-0db8-ec06-dd5f-baec420513c3@imap.cc
Backpatch-through: 10
These have been found while cross-checking for the use of unique words
in the documentation, and a wait event was not getting generated in a way
consistent to what the documentation provided.
Author: Alexander Lakhin
Discussion: https://postgr.es/m/9b5a3a85-899a-ae62-dbab-1e7943aa5ab1@gmail.com
Since approximately PostgreSQL 10, it is no longer required that
environment variables at installation time such as PERL, PYTHON, TCLSH
be "full path names", so change that phrasing in the installation
instructions. (The exact time of change appears to differ for PERL
and the others, but it works consistently in PostgreSQL 10.)
Also while we're here document the defaults for PERL and PYTHON, but
since the search list for TCLSH is so long, let's leave that out so we
don't need to maintain a copy of that list in the installation
instructions.
For a long time, plpgsql has allowed trigger functions to parse
references to OLD and NEW even if the current trigger event type didn't
assign a value to one or the other variable; but actually executing such
a reference would fail. The v11 changes to use "expanded records" for
DTYPE_REC variables changed the behavior so that the unassigned variable
now reads as a null composite value. While this behavioral change was
more or less unintentional, it seems that leaving it like this is better
than adding code and complexity to be bug-compatible with the old way.
The change doesn't break any code that worked before, and it eliminates
a gotcha that often required extra code to work around.
Hence, update the docs to say that these variables are "null" not
"unassigned" when not relevant to the event type. And add a regression
test covering the behavior, so that we'll notice if we ever break it
again.
Per report from Kristjan Tammekivi.
Discussion: https://postgr.es/m/CAABK7uL-uC9ZxKBXzo_68pKt7cECfNRv+c35CXZpjq6jCAzYYA@mail.gmail.com
runtime.sgml said that you couldn't change SysV IPC parameters on OpenBSD
except by rebuilding the kernel. That's definitely wrong in OpenBSD 6.x,
and excavation in their man pages says it changed in OpenBSD 3.3.
Update NetBSD and OpenBSD sections to recommend adjustment of the SEMMNI
and SEMMNS settings, which are painfully small by default on those
platforms. (The discussion thread contemplated recommending that
people select POSIX semaphores instead, but the performance consequences
of that aren't really clear, so I'll refrain.)
Remove pointless discussion of SEMMNU and SEMMAP from the FreeBSD
section. Minor other wordsmithing.
Discussion: https://postgr.es/m/27582.1546928073@sss.pgh.pa.us
"$user" in a search_path string is replaced by CURRENT_USER not
SESSION_USER. (It actually was SESSION_USER in the initial implementation,
but we changed it shortly later, and evidently forgot to fix the docs to
match.)
Noted by antonov@stdpr.ru
Discussion: https://postgr.es/m/159151fb45d490c8d31ea9707e9ba99d@stdpr.ru
The source code comments documented this, but the user-facing docs, not
so much. Add a section to Appendix B that discusses it.
In passing, improve a couple other things in Appendix B --- notably,
a long-obsolete claim that time zone abbreviations are looked up in
a fixed table.
Per bug #15527 from Michael Davidson.
Discussion: https://postgr.es/m/15527-f1be0b4dc99ebbe7@postgresql.org
The documentation of CREATE/ALTER ROLE has been missing two things
related to PASSWORD:
- The password value provided needs to be quoted, some places of the
documentation marked the field with quotes, but not others, which led to
confusion.
- PASSWORD NULL was not provided consistently, with ENCRYPTED being not
compatible with it.
Reported-by: Steven Winfield
Author: Michael Paquier
Reviewed-by: David G. Johnston
Discussion: https://postgr.es/m/154282901979.1316.7418475422120496802@wrigleys.postgresql.org
Documenting INCLUDE in the section about unique indexes is confusing,
as complained of by Emilio Platzer. Furthermore, it entirely failed
to explain why you might want to use the feature. The section about
index-only scans is really the right place; it already talked about
making such things the hard way. Rewrite that text to describe INCLUDE
as the normal way to make a covering index.
Also, move that section up a couple of places, as it now seems more
important than some of the stuff we had before it. It still has to
be after expression and partial indexes, since otherwise some of it
would involve forward references.
Discussion: https://postgr.es/m/154031939560.30897.14677735588262722042@wrigleys.postgresql.org
The documentation claimed that an enum type requires "one or more"
labels, but since 1fd9883ff4, zero labels are also allowed.
Reported-by: Lukas Eder <lukas.eder@gmail.com>
Bug: #15356
This didn't actually work: COPY would fail to flush the right files, and
instead would try to flush a non-existing file, causing the whole
transaction to fail.
Cope by raising an error as soon as the command is sent instead, to
avoid a nasty later surprise. Of course, it would be much better to
make it work, but we don't have a patch for that yet, and we don't know
if we'll want to backpatch one when we do.
Reported-by: Tomas Vondra
Author: David Rowley
Reviewed-by: Amit Langote, Steve Singer, Tomas Vondra
On some operating systems, it doesn't make sense to retry fsync(),
because dirty data cached by the kernel may have been dropped on
write-back failure. In that case the only remaining copy of the
data is in the WAL. A subsequent fsync() could appear to succeed,
but not have flushed the data. That means that a future checkpoint
could apparently complete successfully but have lost data.
Therefore, violently prevent any future checkpoint attempts by
panicking on the first fsync() failure. Note that we already
did the same for WAL data; this change extends that behavior to
non-temporary data files.
Provide a GUC data_sync_retry to control this new behavior, for
users of operating systems that don't eject dirty data, and possibly
forensic/testing uses. If it is set to on and the write-back error
was transient, a later checkpoint might genuinely succeed (on a
system that does not throw away buffers on failure); if the error is
permanent, later checkpoints will continue to fail. The GUC defaults
to off, meaning that we panic.
Back-patch to all supported releases.
There is still a narrow window for error-loss on some operating
systems: if the file is closed and later reopened and a write-back
error occurs in the intervening time, but the inode has the bad
luck to be evicted due to memory pressure before we reopen, we could
miss the error. A later patch will address that with a scheme
for keeping files with dirty data open at all times, but we judge
that to be too complicated to back-patch.
Author: Craig Ringer, with some adjustments by Thomas Munro
Reported-by: Craig Ringer
Reviewed-by: Robert Haas, Thomas Munro, Andres Freund
Discussion: https://postgr.es/m/20180427222842.in2e4mibx45zdth5%40alap3.anarazel.de
This hasn't been correct since 9.3 added "latex-longtable".
I left the phraseology "Unique abbreviations are allowed" alone.
It's correct as far as it goes, and we are studiously refraining
from specifying exactly what happens if you give a non-unique
abbreviation. (The answer in the back branches is "you get a
backwards-compatible choice", and the answer in HEAD will shortly
be "you get an error", but there seems no need to mention such
details here.)
Daniel Vérité
Discussion: https://postgr.es/m/cb7e1caf-3ea6-450d-af28-f524903a030c@manitou-mail.org
This commit fixes a set of issues with ON COMMIT actions when used on
partitioned tables and tables with inheritance children:
- Applying ON COMMIT DROP on a partitioned table with partitions or on a
table with inheritance children caused a failure at commit time, with
complains about the children being already dropped as all relations are
dropped one at the same time.
- Applying ON COMMIT DELETE on a partition relying on a partitioned
table which uses ON COMMIT DROP would cause the partition truncation to
fail as the parent is removed first.
The solution to the first problem is to handle the removal of all the
dependencies in one go instead of dropping relations one-by-one, based
on a suggestion from Álvaro Herrera. So instead all the relation OIDs
to remove are gathered and then processed in one round of multiple
deletions.
The solution to the second problem is to reorder the actions, with
truncation happening first and relation drop done after. Even if it
means that a partition could be first truncated, then immediately
dropped if its partitioned table is dropped, this has the merit to keep
the code simple as there is no need to do existence checks on the
relations to drop.
Contrary to a manual TRUNCATE on a partitioned table, ON COMMIT DELETE
does not cascade to its partitions. The ON COMMIT action defined on
each partition gets the priority.
Author: Michael Paquier
Reviewed-by: Amit Langote, Álvaro Herrera, Robert Haas
Discussion: https://postgr.es/m/68f17907-ec98-1192-f99f-8011400517f5@lab.ntt.co.jp
Backpatch-through: 10
Previously it was possible to set client_min_messages to FATAL or PANIC,
which had the effect of suppressing transmission of regular ERROR messages
to the client. Perhaps that seemed like a useful option in the past, but
the trouble with it is that it breaks guarantees that are explicitly made
in our FE/BE protocol spec about how a query cycle can end. While libpq
and psql manage to cope with the omission, that's mostly because they
are not very bright; client libraries that have more semantic knowledge
are likely to get confused. Notably, pgODBC doesn't behave very sanely.
Let's fix this by getting rid of the ability to set client_min_messages
above ERROR.
In HEAD, just remove the FATAL and PANIC options from the set of allowed
enum values for client_min_messages. (This change also affects
trace_recovery_messages, but that's OK since these aren't useful values
for that variable either.)
In the back branches, there was concern that rejecting these values might
break applications that are explicitly setting things that way. I'm
pretty skeptical of that argument, but accommodate it by accepting these
values and then internally setting the variable to ERROR anyway.
In all branches, this allows a couple of tiny simplifications in the
logic in elog.c, so do that.
Also respond to the point that was made that client_min_messages has
exactly nothing to do with the server's logging behavior, and therefore
does not belong in the "When To Log" subsection of the documentation.
The "Statement Behavior" subsection is a better match, so move it there.
Jonah Harris and Tom Lane
Discussion: https://postgr.es/m/7809.1541521180@sss.pgh.pa.us
Discussion: https://postgr.es/m/15479-ef0f4cc2fd995ca2@postgresql.org
The code added by commit c203d6cf8 causes a crash in at least one case,
where a potentially-optimizable expression index has a storage type
different from the input data type. A cursory code review turned up
numerous other problems that seem impractical to fix on short notice.
Andres argued for revert of that patch some time ago, and if additional
senior committers had been paying attention, that's likely what would
have happened, but we were not :-(
At this point we can't just revert, at least not in v11, because that would
mean an ABI break for code touching relcache entries. And we should not
remove the (also buggy) support for the recheck_on_update index reloption,
since it might already be used in some databases in the field. So this
patch just does the as-little-invasive-as-possible measure of disabling
the feature as though recheck_on_update were forced off for all indexes.
I also removed the related regression tests (which would otherwise fail)
and the user-facing documentation of the reloption.
We should undertake a more thorough code cleanup if the patch can't be
fixed, but not under the extreme time pressure of being already overdue
for 11.1 release.
Per report from Ondřej Bouda and subsequent private discussion among
pgsql-release.
Discussion: https://postgr.es/m/20181106185255.776mstcyehnc63ty@alvherre.pgsql
I removed the item about the pg_stat_statements change from
release-11.sgml, as part of a sweep to delete items already committed
in 11.0; but actually we'd best keep it to ensure that people who've
pg_upgraded their databases will take the requisite action. Also make
said action more visible by making it into its own para. Noted by
Jonathan Katz.
exec_stmt_call() tried to extract information out of a CALL statement's
argument list without using expand_function_arguments(), apparently in
the hope of saving a few nanoseconds by not processing defaulted
arguments. It got that quite wrong though, leading to crashes with
named arguments, as well as failure to enforce writability of the
argument for a defaulted INOUT parameter. Fix and simplify the logic
by using expand_function_arguments() before examining the list.
Also, move the argument-examination to just after producing the CALL
command's plan, before invoking the called procedure. This ensures
that we'll track possible changes in the procedure's argument list
correctly, and avoids a hazard of the plan cache being flushed while
the procedure executes.
Also fix assorted falsehoods and omissions in associated documentation.
Per bug #15477 from Alexey Stepanov.
Patch by me, with some help from Pavel Stehule. Back-patch to v11.
Discussion: https://postgr.es/m/15477-86075b1d1d319e0a@postgresql.org
Discussion: https://postgr.es/m/CAFj8pRA6UsujpTs9Sdwmk-R6yQykPx46wgjj+YZ7zxm4onrDyw@mail.gmail.com
The solution arrived at in commit e74dd00f5 presumes that the compiler
has a suitable default -isysroot setting ... but further experience
shows that in many combinations of macOS version, XCode version, Xcode
command line tools version, and phase of the moon, Apple's compiler
will *not* supply a default -isysroot value.
We could potentially go back to the approach used in commit 68fc227dd,
but I don't have a lot of faith in the reliability or life expectancy of
that either. Let's just revert to the approach already shipped in 11.0,
namely specifying an -isysroot switch globally. As a partial response to
the concerns raised by Jakob Egger, adjust the contents of Makefile.global
to look like
CPPFLAGS = -isysroot $(PG_SYSROOT) ...
PG_SYSROOT = /path/to/sysroot
This allows overriding the sysroot path at build time in a relatively
painless way.
Add documentation to installation.sgml about how to use the PG_SYSROOT
option. I also took the opportunity to document how to work around
macOS's "System Integrity Protection" feature.
As before, back-patch to all supported versions.
Discussion: https://postgr.es/m/20840.1537850987@sss.pgh.pa.us
spgendscan neglected to pfree all the memory allocated by spgbeginscan.
It's possible to get away with that in most normal queries, since the
memory is allocated in the executor's per-query context which is about
to get deleted anyway; but it causes severe memory leakage during
creation or filling of large exclusion-constraint indexes.
Also, document that amendscan is supposed to free what ambeginscan
allocates. The docs' lack of clarity on that point probably caused this
bug to begin with. (There is discussion of changing that API spec going
forward, but I don't think it'd be appropriate for the back branches.)
Per report from Bruno Wolff. It's been like this since the beginning,
so back-patch to all active branches.
In HEAD, also fix an independent leak caused by commit 2a6368343
(allocating memory during spgrescan instead of spgbeginscan, which
might be all right if it got cleaned up, but it didn't). And do a bit
of code beautification on that commit, too.
Discussion: https://postgr.es/m/20181024012314.GA27428@wolff.to
PQnotifies() is defined to just process already-read data, not try to read
any more from the socket. (This is a debatable decision, perhaps, but I'm
hesitant to change longstanding library behavior.) The documentation has
long recommended calling PQconsumeInput() before PQnotifies() to ensure
that any already-arrived message would get absorbed and processed.
However, psql did not get that memo, which explains why it's not very
reliable about reporting notifications promptly.
Also, most (not quite all) callers called PQconsumeInput() just once before
a PQnotifies() loop. Taking this recommendation seriously implies that we
should do PQconsumeInput() before each call. This is more important now
that we have "payload" strings in notification messages than it was before;
that increases the probability of having more than one packet's worth
of notify messages. Hence, adjust code as well as documentation examples
to do it like that.
Back-patch to 9.5 to match related server fixes. In principle we could
probably go back further with these changes, but given lack of field
complaints I doubt it's worthwhile.
Discussion: https://postgr.es/m/CAOYf6ec-TmRYjKBXLLaGaB-jrd=mjG1Hzn1a1wufUAR39PQYhw@mail.gmail.com
With the PostgreSQL 11 release notes acknowledgments list, FOP reported
WARNING: Glyph "?" (0x144, nacute) not available in font "Times-Roman".
WARNING: Glyph "?" (0x15e, Scedilla) not available in font "Times-Roman".
WARNING: Glyph "?" (0x15f, scedilla) not available in font "Times-Roman".
WARNING: Glyph "?" (0x131, dotlessi) not available in font "Times-Roman".
This is because we have some new contributors whose names use letters
that we haven't used before, and apparently FOP can't handle them out
of the box.
For now, just fix this by "unaccenting" those names. In the future,
maybe this can be fixed better with a different font configuration.
There is also another warning
WARNING: Glyph "?" (0x3c0, pi) not available in font "Times-Roman".
but that existed in previous releases and is not touched here.
Set the release date. Do a bunch of copy-editing and markup improvement,
rearrange some stuff into what seemed a more sensible order, move some
things that did not seem to be in the right section.
Historically we forbade datatype-specific comparison functions from
returning INT_MIN, so that it would be safe to invert the sort order
just by negating the comparison result. However, this was never
really safe for comparison functions that directly return the result
of memcmp(), strcmp(), etc, as POSIX doesn't place any such restriction
on those library functions. Buildfarm results show that at least on
recent Linux on s390x, memcmp() actually does return INT_MIN sometimes,
causing sort failures.
The agreed-on answer is to remove this restriction and fix relevant
call sites to not make such an assumption; code such as "res = -res"
should be replaced by "INVERT_COMPARE_RESULT(res)". The same is needed
in a few places that just directly negated the result of memcmp or
strcmp.
To help find places having this problem, I've also added a compile option
to nbtcompare.c that causes some of the commonly used comparators to
return INT_MIN/INT_MAX instead of their usual -1/+1. It'd likely be
a good idea to have at least one buildfarm member running with
"-DSTRESS_SORT_INT_MIN". That's far from a complete test of course,
but it should help to prevent fresh introductions of such bugs.
This is a longstanding portability hazard, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/20180928185215.ffoq2xrq5d3pafna@alap3.anarazel.de
I (Andres) was more than a bit hasty in committing 33001fd7a7
after last minute changes, leading to a number of problems (jit output
was only shown for JIT in parallel workers, and just EXPLAIN without
ANALYZE didn't work). Lukas luckily found these issues quickly.
Instead of combining instrumentation in in standard_ExecutorEnd(), do
so on demand in the new ExplainPrintJITSummary().
Also update a documentation example of the JIT output, changed in
52050ad8eb.
Author: Lukas Fittl, with minor changes by me
Discussion: https://postgr.es/m/CAP53PkxmgJht69pabxBXJBM+0oc6kf3KHMborLP7H2ouJ0CCtQ@mail.gmail.com
Backpatch: 11, where JIT compilation was introduced
Per discussion, JIT isn't quite mature enough to ship enabled-by-default.
I failed to resist the temptation to do a bunch of copy-editing on the
related documentation. Also, clean up some inconsistencies in which
section of config.sgml the JIT GUCs are documented in vs. what guc.c
and postgresql.config.sample had.
Discussion: https://postgr.es/m/20180914222657.mw25esrzbcnu6qlu@alap3.anarazel.de
Commit be54b3777 failed on gmake 3.80 due to a chained conditional,
which on closer examination could be removed entirely with some
refactoring elsewhere for a net simplification and more robustness
against empty expansions. Along the way, add some more comments.
Also make explicit in the documentation and comments that built
headers are not removed by 'make clean', since we don't typically want
that for headers generated by a separate ./configure step, and it's
much easier to add your own 'distclean' rule or use EXTRA_CLEAN than
to try and override a deletion rule in pgxs.mk.
Per buildfarm member prariedog and comments by Michael Paquier, though
all the actual changes are my fault.
Since the fixes for CVE-2018-1058, we've advised people to schema-qualify
function references in order to fix failures in code that executes under
a minimal search_path setting. However, that's insufficient to make the
single-argument form of unaccent() work, because it looks up the "unaccent"
text search dictionary using the search path.
The most expedient answer seems to be to remove the search_path dependency
by making it look in the same schema that the unaccent() function itself
is declared in. This will definitely work for the normal usage of this
function with the unaccent dictionary provided by the extension.
It's barely possible that there are people who were relying on the
search-path-dependent behavior to select other dictionaries with the same
name; but if there are any such people at all, they can still get that
behavior by writing unaccent('unaccent', ...), or possibly
unaccent('unaccent'::text::regdictionary, ...) if the lookup has to be
postponed to runtime.
Per complaint from Gunnlaugur Thor Briem. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/CAPs+M8LCex6d=DeneofdsoJVijaG59m9V0ggbb3pOH7hZO4+cQ@mail.gmail.com
Commit df163230b overlooked the case that an out-of-tree extension
might need to build its header files (e.g. via ./configure). If it is
also doing a VPATH build, the HEADERS_* rules in the original commit
would then fail to find the files, since they would be looking only
under $(srcdir) and not in the build directory.
Fix by adding HEADERS_built and HEADERS_built_$(MODULE) which behave
like DATA_built in that they look in the build dir rather than the
source dir (and also make the files dependencies of the "all" target).
No Windows support appears to be needed for this, since it is only
relevant to out-of-tree builds (no support exists in Mkvcbuild.pm to
build extension header files in any case).
pg_get_object_address and pg_identify_object_as_address are supposed
to be inverses, but they disagreed as to the names of the arguments
representing the textual form of an object address. Moreover, the
documented argument names didn't agree with reality at all, either
for these functions or pg_identify_object.
In HEAD and v11, I think we can get away with renaming the input
arguments of pg_get_object_address to match the outputs of
pg_identify_object_as_address. In theory that might break queries
using named-argument notation to call pg_get_object_address, but
it seems really unlikely that anybody is doing that, or that they'd
have much trouble adjusting if they were. In older branches, we'll
just live with the lack of consistency.
Aside from fixing the documentation of these functions to match reality,
I couldn't resist the temptation to do some copy-editing.
Per complaint from Jean-Pierre Pelletier. Back-patch to 9.5 where these
functions were introduced. (Before v11, this is a documentation change
only.)
Discussion: https://postgr.es/m/CANGqjDnWH8wsTY_GzDUxbt4i=y-85SJreZin4Hm8uOqv1vzRQA@mail.gmail.com
The previous description was unclear. Also add a third example, change
use of time zone acronyms to more verbose descriptions, and add a
mention that using 'time' with AT TIME ZONE uses the current time zone
rules.
Backpatch-through: 9.3
It's been true for a long time that we expect names of table and domain
constraints to be unique among the constraints of that table or domain.
However, the enforcement of that has been pretty haphazard, and it missed
some corner cases such as creating a CHECK constraint and then an index
constraint of the same name (as per recent report from André Hänsel).
Also, due to the lack of an actual unique index enforcing this, duplicates
could be created through race conditions.
Moreover, the code that searches pg_constraint has been quite inconsistent
about how to handle duplicate names if one did occur: some places checked
and threw errors if there was more than one match, while others just
processed the first match they came to.
To fix, create a unique index on (conrelid, contypid, conname). Since
either conrelid or contypid is zero, this will separately enforce
uniqueness of constraint names among constraints of any one table and any
one domain. (If we ever implement SQL assertions, and put them into this
catalog, more thought might be needed. But it'd be at least as reasonable
to put them into a new catalog; having overloaded this one catalog with
two kinds of constraints was a mistake already IMO.) This index can replace
the existing non-unique index on conrelid, though we need to keep the one
on contypid for query performance reasons.
Having done that, we can simplify the logic in various places that either
coped with duplicates or neglected to, as well as potentially improve
lookup performance when searching for a constraint by name.
Also, as per our usual practice, install a preliminary check so that you
get something more friendly than a unique-index violation report in the
case complained of by André. And teach ChooseIndexName to avoid choosing
autogenerated names that would draw such a failure.
While it's not possible to make such a change in the back branches,
it doesn't seem quite too late to put this into v11, so do so.
Discussion: https://postgr.es/m/0c1001d4428f$0942b430$1bc81c90$@webkr.de
This column was added in commit 8224de4f42 ("Indexes with INCLUDE
columns and their support in B-tree") to ease writing the ruleutils.c
supporting code for that feature, but it turns out to be unnecessary --
we can do the same thing with just one more syscache lookup.
Even the documentation for the new column being removed in this commit
is awkward.
Discussion: https://postgr.es/m/20180902165018.33otxftp3olgtu4t@alvherre.pgsql
This table claimed that JOHAB could be used as a server encoding, which
was true originally but hasn't been true since 8.3. It also lacked
entries for EUC_JIS_2004 and SHIFT_JIS_2004.
JOHAB problem noted by Lars Kanis, the others by me.
Discussion: https://postgr.es/m/c0f514a1-b7a9-b9ea-1c02-c34aead56c06@greiz-reinsdorf.de
Using -d is odd, because we normally reserve that for a database
argument, so rename it to -v and add long version --verbose.
Also, reduce it to emit one line per file checked rather than one line
per block.
Per a complaint from Michael Banck.
Author: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Michael Banck <michael.banck@credativ.de>
Discussion: https://postgr.es/m/20180827113411.GA22768@nighthawk.caipicrew.dd-dns.de
Mention that "Latest checkpoint location" will not match in pg_upgrade
if the standby server is still running during the upgrade, which is
possible. "Match" text first appeared in PG 9.5.
Reported-by: Paul Bonaud
Discussion: https://postgr.es/m/c7268794-edb4-1772-3bfd-04c54585c24e@trainline.com
Backpatch-through: 9.5
Historically, we looked up the target hostname in connectDBStart, so that
PQconnectPoll did not need to do DNS name resolution. The patches that
added multiple-target-host support to libpq preserved this division of
labor; but it's really nonsensical now, because it means that if any one
of the target hosts fails to resolve in DNS, the connection fails. That
negates the no-single-point-of-failure goal of the feature. Additionally,
DNS lookups aren't exactly cheap, but the code did them all even if the
first connection attempt succeeds.
Hence, rearrange so that PQconnectPoll does the lookups, and only looks
up a hostname when it's time to try that host. This does mean that
PQconnectPoll could block on a DNS lookup --- but if you wanted to avoid
that, you should be using hostaddr, as the documentation has always
specified. It seems fairly unlikely that any applications would really
care whether the lookup occurs inside PQconnectStart or PQconnectPoll.
In addition to calling out that fact explicitly, do some other minor
wordsmithing in the docs around the multiple-target-host feature.
Since this seems like a bug in the multiple-target-host feature,
backpatch to v10 where that was introduced. In the back branches,
avoid moving any existing fields of struct pg_conn, just in case
any third-party code is looking into that struct.
Tom Lane, reviewed by Fabien Coelho
Discussion: https://postgr.es/m/4913.1533827102@sss.pgh.pa.us
Since procedures are now a different thing from functions, change the
CREATE TRIGGER and CREATE EVENT TRIGGER syntax to use FUNCTION in the
clause that specifies the function. PROCEDURE is still accepted for
compatibility.
pg_dump and ruleutils.c output is not changed yet, because that would
require a change in information_schema.sql and thus a catversion change.
Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
Since procedures are now a different thing from functions, change the
CREATE OPERATOR syntax to use FUNCTION in the clause that specifies the
function. PROCEDURE is still accepted for compatibility.
Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
Historically, the term procedure was used as a synonym for function in
Postgres/PostgreSQL. Now we have procedures as separate objects from
functions, so we need to clean up the documentation to not mix those
terms.
In particular, mentions of "trigger procedures" are changed to "trigger
functions", and access method "support procedures" are changed to
"support functions". (The latter already used FUNCTION in the SQL
syntax anyway.) Also, the terminology in the SPI chapter has been
cleaned up.
A few tests, examples, and code comments are also adjusted to be
consistent with documentation changes, but not everything.
Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
Commit 5f374fe7a attempted to turn the connect_timeout from an overall
maximum time limit into a per-host limit, but it didn't do a great job of
that. The timer would only get restarted if we actually detected timeout
within connectDBComplete(), not if we changed our attention to a new host
for some other reason. In that case the old timeout continued to run,
possibly causing a premature timeout failure for the new host.
Fix that, and also tweak the logic so that if we do get a timeout,
we advance to the next available IP address, not to the next host name.
There doesn't seem to be a good reason to assume that all the IP
addresses supplied for a given host name will necessarily fail the
same way as the current one. Moreover, this conforms better to the
admittedly-vague documentation statement that the timeout is "per
connection attempt". I changed that to "per host name or IP address"
to be clearer. (Note that reconnections to the same server, such as for
switching protocol version or SSL status, don't get their own separate
timeout; that was true before and remains so.)
Also clarify documentation about the interpretation of connect_timeout
values less than 2.
This seems like a bug, so back-patch to v10 where this logic came in.
Tom Lane, reviewed by Fabien Coelho
Discussion: https://postgr.es/m/5735.1533828184@sss.pgh.pa.us
5262f7a4fc have introduced parallel index scan. In order to estimate the
number of parallel workers, it adds extra argument to amcostestimate() index
access method API function. However, this extra argument was missed in the
documentation. This commit fixes that.
Discussion: https://postgr.es/m/4128fdb4-8b63-2e05-38f6-3125f8c27263%40lab.ntt.co.jp
Author: Tatsuro Yamada, Alexander Korotkov
Backpatch-through: 10
Since commit 3b8f6e75f, failure to do this would lead to
submake-generated-headers not doing anything, so that references to
generated or symlinked headers would fail. Previous to that, the
omission only led to temp-install not doing anything, which apparently
affects many fewer people (doesn't anybody use "make check" in their
build rules??). Hence, backpatch to v11 but not further.
Per complaints from Christoph Berg, Jakob Egger, and others.
A database owner running a database-level REINDEX has the possibility to
also do the operation on shared system catalogs without being an owner
of them, which allows him to block resources it should not have access
to. The same goes for a schema owner. For example, PostgreSQL would go
unresponsive and even block authentication if a lock is waited for
pg_authid. This commit makes sure that a user running a REINDEX SYSTEM,
DATABASE or SCHEMA only works on the following relations:
- The user is a superuser
- The user is the table owner
- The user is the database/schema owner, only if the relation worked on
is not shared.
Robert has worded most the documentation changes, and I have coded the
core part.
Reported-by: Lloyd Albin, Jeremy Schneider
Author: Michael Paquier, Robert Haas
Reviewed by: Nathan Bossart, Kyotaro Horiguchi
Discussion: https://postgr.es/m/152512087100.19803.12733865831237526317@wrigleys.postgresql.org
Discussion: https://postgr.es/m/20180805211059.GA2185@paquier.xyz
Backpatch-through: 11- as the current behavior has been around for a
very long time and could be disruptive for already released branches.
The amcheck documentation incorrectly claimed that its example query
verifies every catalog index in the database. In fact, the query only
verifies the 10 largest indexes (as determined by pg_class.relpages).
Adjust the description accordingly.
Backpatch: 10-, where contrib/amcheck was introduced.
There are some problems with the tls-unique channel binding type. It's not
supported by all SSL libraries, and strictly speaking it's not defined for
TLS 1.3 at all, even though at least in OpenSSL, the functions used for it
still seem to work with TLS 1.3 connections. And since we had no
mechanism to negotiate what channel binding type to use, there would be
awkward interoperability issues if a server only supported some channel
binding types. tls-server-end-point seems feasible to support with any SSL
library, so let's just stick to that.
This removes the scram_channel_binding libpq option altogether, since there
is now only one supported channel binding type.
This also removes all the channel binding tests from the SSL test suite.
They were really just testing the scram_channel_binding option, which
is now gone. Channel binding is used if both client and server support it,
so it is used in the existing tests. It would be good to have some tests
specifically for channel binding, to make sure it really is used, and the
different combinations of a client and a server that support or doesn't
support it. The current set of settings we have make it hard to write such
tests, but I did test those things manually, by disabling
HAVE_BE_TLS_GET_CERTIFICATE_HASH and/or
HAVE_PGTLS_GET_PEER_CERTIFICATE_HASH.
I also removed the SCRAM_CHANNEL_BINDING_TLS_END_POINT constant. This is a
matter of taste, but IMO it's more readable to just use the
"tls-server-end-point" string.
Refactor the checks on whether the SSL library supports the functions
needed for tls-server-end-point channel binding. Now the server won't
advertise, and the client won't choose, the SCRAM-SHA-256-PLUS variant, if
compiled with an OpenSSL version too old to support it.
In the passing, add some sanity checks to check that the chosen SASL
mechanism, SCRAM-SHA-256 or SCRAM-SHA-256-PLUS, matches whether the SCRAM
exchange used channel binding or not. For example, if the client selects
the non-channel-binding variant SCRAM-SHA-256, but in the SCRAM message
uses channel binding anyway. It's harmless from a security point of view,
I believe, and I'm not sure if there are some other conditions that would
cause the connection to fail, but it seems better to be strict about these
things and check explicitly.
Discussion: https://www.postgresql.org/message-id/ec787074-2305-c6f4-86aa-6902f98485a4%40iki.fi
Remove description of commit 1944cdc98, which has now been back-patched
so it's not relevant to v11 any longer. Add descriptions of other
recent commits that seemed worth mentioning.
I marked the update as stopping at 2018-07-30, because it's unclear
whether d06eebce5 will be allowed to stay in v11, and I didn't feel like
putting effort into writing a description of it yet. If it does stay,
I think it will deserve mention in the Source Code section.
The example output of pg_replication_slot is wrong. Correct it and make
the output stable by explicitly listing columns to output.
Author: Kyotaro Horiguchi <horiguchi.kyotaro@lab.ntt.co.jp>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/20180731.190909.42582169.horiguchi.kyotaro@lab.ntt.co.jp
Before v10, we always searched ~/.pgpass using the host parameter,
and nothing else, to match to the "hostname" field of ~/.pgpass.
(However, null host or host matching DEFAULT_PGSOCKET_DIR was replaced by
"localhost".) In v10, this got broken by commit 274bb2b38, repaired by
commit bdac9836d, and broken again by commit 7b02ba62e; in the code
actually shipped, we'd search with hostaddr if both that and host were
specified --- though oddly, *not* if only hostaddr were specified.
Since this is directly contrary to the documentation, and not
backwards-compatible, it's clearly a bug.
However, the change wasn't totally without justification, even though it
wasn't done quite right, because the pre-v10 behavior has arguably been
buggy since we added hostaddr. If hostaddr is specified and host isn't,
the pre-v10 code will search ~/.pgpass for "localhost", and ship that
password off to a server that most likely isn't local at all. That's
unhelpful at best, and could be a security breach at worst.
Therefore, rather than just revert to that old behavior, let's define
the behavior as "search with host if provided, else with hostaddr if
provided, else search for localhost". (As before, a host name matching
DEFAULT_PGSOCKET_DIR is replaced by localhost.) This matches the
behavior of the actual connection code, so that we don't pick up an
inappropriate password; and it allows useful searches to happen when
only hostaddr is given.
While we're messing around here, ensure that empty elements within a
host or hostaddr list select the same behavior as a totally-empty
field would; for instance "host=a,,b" is equivalent to "host=a,/tmp,b"
if DEFAULT_PGSOCKET_DIR is /tmp. Things worked that way in some cases
already, but not consistently so, which contributed to the confusion
about what key ~/.pgpass would get searched with.
Update documentation accordingly, and also clarify some nearby text.
Back-patch to v10 where the host/hostaddr list functionality was
introduced.
Discussion: https://postgr.es/m/30805.1532749137@sss.pgh.pa.us
This allows out-of-tree PLs and similar code to get access to
definitions needed to work with extension data types.
The following existing modules now install headers: contrib/cube,
contrib/hstore, contrib/isn, contrib/ltree, contrib/seg.
Discussion: https://postgr.es/m/87y3euomjh.fsf%40news-spur.riddles.org.uk
As written, this policy constrained only the post-image not the pre-image
of rows, meaning that users could delete other users' rows or take
ownership of such rows, contrary to what the docs claimed would happen.
We need two separate policies to achieve the documented effect.
While at it, try to explain what's happening a bit more fully.
Per report from Олег Самойлов. Back-patch to 9.5 where this was added.
Thanks to Stephen Frost for off-list discussion.
Discussion: https://postgr.es/m/3298321532002010@sas1-2b3c3045b736.qloud-c.yandex.net
Commit 5770172cb0 documented secure schema
usage, and that advice suffices for using unqualified names securely.
Document, in typeconv-func primarily, the additional issues that arise
with qualified names. Back-patch to 9.3 (all supported versions).
Reviewed by Jonathan S. Katz.
Discussion: https://postgr.es/m/20180721012446.GA1840594@rfd.leadboat.com
The initial version of the included-index-column feature stated that
included columns couldn't be the same as any key column of the index.
While it'd be pretty silly to do that, since the included column would be
entirely redundant, we've never prohibited redundant index columns before
so it's not very consistent to do so here. Moreover, the prohibition
was itself badly implemented, so that it failed to reject columns that
were effectively identical but not spelled quite alike, as reported by
Aditya Toshniwal.
(Moreover, it's not hard to imagine that for some non-btree index types,
such cases would be non-silly anyhow: the index might use a lossy
representation for key columns but be able to support retrieval of the
original form of included columns.)
Hence, let's just drop the prohibition.
In passing, do some copy-editing on the documentation for the
included-column feature.
Yugo Nagata; documentation and test corrections by me
Discussion: https://postgr.es/m/CAM9w-_mhBCys4fQNfaiQKTRrVWtoFrZ-wXmDuE9Nj5y-Y7aDKQ@mail.gmail.com
A collection of typos I happened to spot while reading code, as well as
grepping for common mistakes.
Backpatch to all supported versions, as applicable, to avoid conflicts
when backporting other commits in the future.
It's more logical this way, since the new ordering matches the way the
tables are created; but in any case, the previous location of PARTITION OF
did not appear carefully chosen anyway (since it didn't match the
location in which it appears in the synopsys either, which is what we
normally do.)
In the PARTITION BY stanza, add a link to the partitioning section in
the DDL chapter, too.
Suggested-by: David G. Johnston
Discussion: https://postgr.es/m/CAKFQuwY4Ld7ecxL_KAmaxwt0FUu5VcPPN2L4dh+3BeYbrdBa5g@mail.gmail.com
Update links that resulted in redirects. Most are changes from http to
https, but there are also some other minor edits. (There are still some
redirects where the target URL looks less elegant than the one we
currently have. I have left those as is.)
lca_inner() wasn't prepared for the possibility of getting no inputs.
Fix that, and make some cosmetic improvements to the code while at it.
Also, I thought the documentation of this function as returning the
"longest common prefix" of the paths was entirely misleading; it really
returns a path one shorter than the longest common prefix, for the typical
definition of "prefix". Don't use that term in the docs, and adjust the
examples to clarify what really happens.
This has been broken since its beginning, so back-patch to all supported
branches.
Per report from Hailong Li. Thanks to Pierre Ducroquet for diagnosing
and for the initial patch, though I whacked it around some and added
test cases.
Discussion: https://postgr.es/m/5b0d8e4f-f2a3-1305-d612-e00e35a7be66@qunar.com
Now that the documentation sources are in XML rather than SGML, some of
the documentation about the editor, or more specifically Emacs, setup
needs updating. The updated instructions recommend using nxml-mode,
which works mostly out of the box, with some small tweaks in
emacs.samples and .dir-locals.el.
Also remove some obsolete stuff in .dir-locals.el. I did, however,
leave the sgml-mode settings in there so that someone using Emacs
without emacs.samples gets those settings when editing a *.sgml file.
Starting and aborting transactions in security definer procedures
doesn't work. StartTransaction() insists that the security context
stack is empty, so this would currently cause a crash, and
AbortTransaction() resets it. This could be made to work by
reorganizing the code, but right now we just prohibit it.
Reported-by: amul sul <sulamul@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b96Gupt_LFL7uNyy3c50-wbhA68NUjiK5%3DrF6_w%3Dpq_T%3DQ%40mail.gmail.com
Explain that you can use any integer expression for the "count" in
pl/pgsql's versions of FETCH/MOVE, unlike the SQL versions which only
allow a constant.
Remove the duplicate version of this para under MOVE. I don't see
a good reason to maintain two identical paras when we just said that
MOVE works exactly like FETCH.
Per Pavel Stehule, though I didn't use his text.
Discussion: https://postgr.es/m/CAFj8pRAcvSXcNdUGx43bOK1e3NNPbQny7neoTLN42af+8MYWEA@mail.gmail.com
Commit ff4f88916 adjusted the code to enforce the SQL spec's requirement
that a window using GROUPS mode must have an ORDER BY clause. But I missed
that the documentation explicitly said you didn't have to have one.
Also minor wordsmithing in the window-function section of select.sgml.
Per Masahiko Sawada, though I didn't use his patch.
Such replication slots are physical slots freshly created without WAL
being reserved, which is the default behavior, which have not been used
yet as WAL consumption resources to retain WAL. This prevents advancing
a slot to a position older than any WAL available, which could falsify
calculations for WAL segment recycling.
This also cleans up a bit the code, as ReplicationSlotRelease() would be
called on ERROR, and improves error messages.
Reported-by: Kyotaro Horiguchi
Author: Michael Paquier
Reviewed-by: Andres Freund, Álvaro Herrera, Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180626071305.GH31353@paquier.xyz
When performing pg_rewind, the presence of a read-only file which is not
accessible for writes will cause a failure while processing. This can
cause the control file of the target data folder to be truncated,
causing it to not be reusable with a successive run.
Also, when pg_rewind fails mid-flight, there is likely no way to be able
to recover the target data folder anyway, in which case a new base
backup is the best option. A note is added in the documentation as
well about.
Reported-by: Christian H.
Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/20180104200633.17004.16377%40wrigleys.postgresql.org
Prefer to use phrases like "child" instead of "partition" when
describing the legacy inheritance-based partitioning. The word
"partition" now has a fixed meaning for the built-in partitioning, so
keeping it out of the documentation of the old method makes things
clearer.
Author: Justin Pryzby <pryzby@telsasoft.com>
Committer: Peter Eisentraut <peter_e@gmx.net>
Backpatch of: 0c06534bd6
When these programs call pg_catalog.set_config, they need to check for
PGRES_TUPLES_OK instead of PGRES_COMMAND_OK. Fix for
5770172cb0.
Reported-by: Ideriha, Takeshi <ideriha.takeshi@jp.fujitsu.com>
search.cpan.org has been EOL'd, with metacpan.org being the official
replacement to which URLs now redirect. Update links to match the new
URL. Also update links to CPAN to use https as it will redirect from
http.
Author: Daniel Gustafsson
Discussion: https://postgr.es/m/B74C0219-6BA9-46E1-A524-5B9E8CD3BDB3@yesql.se
The backup history file has been no longer necessary for recovery
since the version 9.0. It's now basically just for informational purpose.
But previously the documentations still described that a recovery
requests the backup history file to proceed. The commit fixes this
documentation bug.
Back-patch to all supported versions.
Author: Yugo Nagata
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180626174752.0ce505e3.nagata@sraoss.co.jp
Upper limits for vacuum_cleanup_index_scale_factor GUC and reloption
were initially set to 100.0 in 857f9c36. However, after further
discussion, it appears that some users like to disable B-tree cleanup
index scan completely (assuming there are no deleted pages).
vacuum_cleanup_index_scale_factor is used barely to protect against
stalled index statistics. And after detailed consideration it appears
that risk of stalled index statistics is low. And it would be nice to
allow advanced users setting higher values of
vacuum_cleanup_index_scale_factor. So, set upper limit for these
GUC and reloption to DBL_MAX.
Author: Alexander Korotkov
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/CAC8Q8tJCb%3DgxhzcV7T6ctx7PY-Ux1oA-AsTJc6cAVNsQiYcCzA%40mail.gmail.com
vacuum_cleanup_index_scale_factor was located in autovacuum group of
GUCs. However, it affects not only autovacuum, but also manually run
VACUUM. It appears that "client connection defaults" group of GUCs
is more appropriate for vacuum_cleanup_index_scale_factor, because
vacuum_*_age options are already located there.
Also, vacuum_cleanup_index_scale_factor was missed in
postgresql.conf.sample. So, add it there with appropriate comment.
Author: Masahiko Sawada with minor editorization by me
Discussion: https://postgr.es/m/CAD21AoArsoXMLKudXSKN679FRzs6oubEchM53bHwn8Tp%3D2boNg%40mail.gmail.com
Pavel Stehule's original patch had support for default namespace, but I
ripped it out before commit -- hence the docs were correct when written,
and I broke them by omission :-(. Remove the offending phrase.
Author: Daniel Gustafsson
Discussion: https://postgr.es/m/1550C5E5-FC70-4493-A226-AA137D831E8D@yesql.se
PostgreSQL 11 introduces compress method for SP-GiST opclasses. That
was mistakenly interpreted as compression support for SP-GiST while
actually that allows lossy representation of leaf keys.
Author: Alexander Korotkov, based on proposal by Darafei Praliaskouski
Discussion: https://postgr.es/m/CAC8Q8tKbYmNdiyWr7hE4GfMY4fbqHKkFziKgrUuWHH6HJQs3og%40mail.gmail.com
Since their introduction, partition trees have been a bit lossy
regarding temporary relations. Inheritance trees respect the following
patterns:
1) a child relation can be temporary if the parent is permanent.
2) a child relation can be temporary if the parent is temporary.
3) a child relation cannot be permanent if the parent is temporary.
4) The use of temporary relations also imply that when both parent and
child need to be from the same sessions.
Partitions share many similar patterns with inheritance, however the
handling of the partition bounds make the situation a bit tricky for
case 1) as the partition code bases a lot of its lookup code upon
PartitionDesc which does not really look after relpersistence. This
causes for example a temporary partition created by session A to be
visible by another session B, preventing this session B to create an
extra partition which overlaps with the temporary one created by A with
a non-intuitive error message. There could be use-cases where mixing
permanent partitioned tables with temporary partitions make sense, but
that would be a new feature. Partitions respect 2), 3) and 4) already.
It is a bit depressing to see those error checks happening in
MergeAttributes() whose purpose is different, but that's left as future
refactoring work.
Back-patch down to 10, which is where partitioning has been introduced,
except that default partitions do not apply there. Documentation also
includes limitations related to the use of temporary tables with
partition trees.
Reported-by: David Rowley
Author: Amit Langote, Michael Paquier
Reviewed-by: Ashutosh Bapat, Amit Langote, Michael Paquier
Discussion: https://postgr.es/m/CAKJS1f94Ojk0og9GMkRHGt8wHTW=ijq5KzJKuoBoqWLwSVwGmw@mail.gmail.com
Postgres has traditionally considered the syntactic forms f(x) and x.f
to be equivalent, allowing tricks such as writing a function and then
using it as though it were a computed-on-demand column. However, our
behavior when both interpretations are feasible left something to be
desired: we always chose the column interpretation. This could lead
to very surprising results, as in a recent bug report from Neil Conway.
It also created a dump-and-reload hazard, since what was a function
call in a dumped view could get interpreted as a column reference
at reload, if a matching column name had been added to the underlying
table since the view was created.
What seems better, in ambiguous situations, is to prefer the choice
matching the syntactic form of the reference. This seems much less
astonishing in general, and it fixes the dump/reload hazard.
Although this could be called a bug fix, there have been few complaints
and there's some small risk of breaking applications that depend on the
old behavior, so no back-patch. It does seem reasonable to slip it
into v11, though.
Discussion: https://postgr.es/m/CAOW5sYa3Wp7KozCuzjOdw6PiOYPi6D=VvRybtH2S=2C0SVmRmA@mail.gmail.com
On Windows, it is sometimes important for corresponding malloc() and
free() calls to be made from the same DLL, since some build options can
result in multiple allocators being active at the same time. For that
reason we already provided PQfreemem(). This commit adds a similar
function for freeing string results allocated by the pgtypes library.
Author: Takayuki Tsunakawa
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8AD5D6%40G01JPEXMBYT05
Documentation of word_similarity() and strict_word_similarity() functions
contains some vague wordings which could confuse users. This patch makes
those wordings more clear. word_similarity() was introduced in PostgreSQL 9.6,
and corresponding part of documentation needs to be backpatched.
Author: Bruce Momjian, Alexander Korotkov
Discussion: https://postgr.es/m/20180526165648.GB12510%40momjian.us
Backpatch: 9.6, where word_similarity() was introduced
kern.ipc.shm_use_phys is not a sysctl on OpenBSD, and SEMMAP is not
a kernel configuration option. These were probably copy pasteos from
when the documentation had a single paragraph for *BSD.
Author: Daniel Gustafsson <daniel@yesql.se>
OFFSET <x> ROWS FETCH FIRST <y> ROWS ONLY syntax is supposed to accept
<simple value specification>, which includes parameters as well as
literals. When this syntax was added all those years ago, it was done
inconsistently, with <x> and <y> being different subsets of the
standard syntax.
Rectify that by making <x> and <y> accept the same thing, and allowing
either a (signed) numeric literal or a c_expr there, which allows for
parameters, variables, and parenthesized arbitrary expressions.
Per bug #15200 from Lukas Eder.
Backpatch all the way, since this has been broken from the start.
Discussion: https://postgr.es/m/877enz476l.fsf@news-spur.riddles.org.uk
Discussion: http://postgr.es/m/152647780335.27204.16895288237122418685@wrigleys.postgresql.org
An xref to a <para>'s ID isn't very helpful because paras don't have
names. This causes a warning while building PDFs, though for some
reason not while building HTML. The link arguably went to the wrong
place, too.
To fix, introduce a sub-section we can reference.
The "l" (ell) width spec means something in the corresponding scanf usage,
but not here. While modern POSIX says that applying "l" to "f" and other
floating format specs is a no-op, SUSv2 says it's undefined. Buildfarm
experience says that some old compilers emit warnings about it, and at
least one old stdio implementation (mingw's "ANSI" option) actually
produces wrong answers and/or crashes.
Discussion: https://postgr.es/m/21670.1526769114@sss.pgh.pa.us
Discussion: https://postgr.es/m/c085e1da-0d64-1c15-242d-c921f32e0d5c@dunslane.net
The description of the index property backward_scan was incorrect and
misleading; rectify.
Backpatch to 9.6 where the amutils functionality was introduced.
Explain partition pruning more thoroughly, in a section above the one
that explains constraint exclusion, since the new feature is the one
that will be used more extensively from now on. Move some of the
material from the constraint exclusion subsection to the one on
partition pruning, so that we can explain the legacy method by
explaining the differences with the new one instead of repeating it.
Author: David Rowley, Álvaro Herrera
Reviewed-by: Amit Langote, David G. Johnston, Justin Pryzby
Discussion: https://postgr.es/m/CAKJS1f8PECxEi1YQ9nhVtshtfOMHUzAMm_Zp4gGCOCnMPjEKJA@mail.gmail.com
I get "WARNING: nested link may be undefined in output: <xref @linkend =
'pgbench'> nested inside parent element link" from this.
Also remove some trailing whitespace.
- Change vacuum_cleanup_index_scale_factor GUC to PGC_USERSET.
vacuum_cleanup_index_scale_factor GUC was defined as PGC_SIGHUP. But this
GUC affects not only autovacuum. So it might be useful to change it from user
session in order to influence manually runned VACUUM.
- Add missing tab-complete support for vacuum_cleanup_index_scale_factor
reloption.
- Fix condition for B-tree index cleanup.
Zero value of vacuum_cleanup_index_scale_factor means that user wants B-tree
index cleanup to be never skipped.
- Documentation and comment improvements
Authors: Justin Pryzby, Alexander Korotkov, Liudmila Mantrova
Reviewed by: all authors and Robert Haas
Discussion: https://www.postgresql.org/message-id/flat/20180502023025.GD7631%40telsasoft.com
The set of functions that need parallel-safety adjustments isn't the
same in 9.6 as 10, so I shouldn't have blindly back-patched that list.
Adjust as needed. Also, provide examples of the commands to issue.
There shouldn't be a line break between two adjacent tags, because that
will appear as whitespace in the output. (The rendering engine might in
turn collapse that whitespace away, so it might not actually make a
difference, but it's more correct this way.)
Mark Dilger pointed out that the bootstrap parser does not allow
any of its keywords to appear as column values unless they're quoted,
and proposed dealing with that by quoting such values in genbki.pl.
Looking closer, though, we also have that problem with respect to table,
column, and type names appearing in the .bki file: the parser would fail
if any of those matched any of its keywords. While so far there have
been no conflicts (that I've heard of), this seems like a booby trap
waiting to catch somebody. Rather than clutter genbki.pl with enough
quoting logic to handle all that, let's make the bootstrap parser grow
up a little bit and treat its keywords as unreserved.
Experimentation shows that it's fairly easy to do so with the exception
of _null_, which I don't have a big problem with keeping as a reserved
word. The only change needed is that we can't have the "close" command
take an optional table name: it has to either require or forbid the
table name to avoid shift/reduce conflicts. genbki.pl has historically
always included the table name, so I took that option.
The implementation has bootscanner.l passing forward the string value
of each keyword, in case bootparse.y needs that. This avoids needing to
know the precise spelling of each keyword in bootparse.y, which is good
because that's not always obvious from the token name.
Discussion: https://postgr.es/m/3024FC91-DB6D-4732-B31C-DF772DF039A0@gmail.com
Use the same code we already applied in duplicate_oids and unused_oids
to let this script find Catalog.pm without help. This removes the need
to supply a -I switch in most cases.
Also, mark the script executable, again to follow the precedent of
duplicate_oids and unused_oids. Now you can just do
"./reformat_dat_file.pl pg_proc.dat"
if you want to reformat only one or a few .dat files rather than all.
It'd be possible to remove the -I switches in the Makefile's convenience
targets, but I chose to leave them: they don't hurt anything, and it's
possible that in weird VPATH situations they might be of value.
Identify pg_replication_origin as a shared catalog in catalogs.sgml,
using the same boilerplate wording used for most other shared catalogs
(and tweak another place where someone had randomly deviated from
that boilerplate).
Make an example in mmgr/README more consistent with surrounding text.
Update an obsolete cross-reference in a comment in storage/block.h.
Zhuo Ql
Discussion: https://postgr.es/m/44296255.1819230.1524889719001@mail.yahoo.com
In the wake of commit 5602265f7, we were doing duplicate-OID detection
quite inefficiently, by invoking duplicate_oids which does all the same
parsing of catalog headers and .dat files as genbki.pl does. That adds
under half a second on modern machines, but quite a bit more on slow
buildfarm critters, so it seems worth avoiding. Let's just extend
genbki.pl a little so it can also detect duplicate OIDs, and remove
the duplicate_oids call from the build process.
(This also means that duplicate OID detection will happen during
Windows builds, which AFAICS it didn't before.)
This makes the use-case for duplicate_oids a bit dubious, but it's
possible that people will still want to run that check without doing
a whole build run, so let's keep that script.
In passing, move down genbki.pl's creation of its temp output files
so that it doesn't happen until after we've done parsing and validation
of the input. This avoids leaving a lot of clutter around after a
failure.
John Naylor and Tom Lane
Discussion: https://postgr.es/m/37D774E4-FE1F-437E-B3D2-593F314B7505@postgrespro.ru
When bt_index_parent_check() is called with the heapallindexed option,
allocate a second Bloom filter to fingerprint block numbers that appear
in the downlinks of internal pages. Use Bloom filter probes when
walking the B-Tree to detect missing downlinks. This can detect subtle
problems with page deletion/VACUUM, such as corruption caused by the bug
just fixed in commit 6db4b499.
The downlink Bloom filter is bound in size by work_mem. Its optimal
size is typically far smaller than that of the regular heapallindexed
Bloom filter, especially when the index has high fan-out.
Author: Peter Geoghegan
Reviewer: Teodor Sigaev
Discussion: https://postgr.es/m/CAH2-WznUzY4fWTjm1tBB3JpVz8cCfz7k_qVp5BhuPyhivmWJFg@mail.gmail.com
This controls both plan-time and execution-time new-style partition
pruning. While finer-grain control is possible (maybe using an enum GUC
instead of boolean), there doesn't seem to be much need for that.
This new parameter controls partition pruning for all queries:
trivially, SELECT queries that affect partitioned tables are naturally
under its control since they are using the new technology. However,
while UPDATE/DELETE queries do not use the new code, we make the new GUC
control their behavior also (stealing control from
constraint_exclusion), because it is more natural, and it leads to a
more natural transition to the future in which those queries will also
use the new pruning code.
Constraint exclusion still controls pruning for regular inheritance
situations (those not involving partitioned tables).
Author: David Rowley
Review: Amit Langote, Ashutosh Bapat, Justin Pryzby, David G. Johnston
Discussion: https://postgr.es/m/CAKJS1f_0HwsxJG9m+nzU+CizxSdGtfe6iF_ykPYBiYft302DCw@mail.gmail.com
Previously, you could partition by a boolean column as long as you
spelled the bound values as string literals, for instance FOR VALUES
IN ('t'). The trouble with this is that ruleutils.c printed that as
FOR VALUES IN (TRUE), which is reasonable syntax but wasn't accepted by
the grammar. That results in dump-and-reload failures for such cases.
Apply a minimal fix that just causes TRUE and FALSE to be converted to
strings 'true' and 'false'. This is pretty grotty, but it's too late for
a more principled fix in v11 (to say nothing of v10). We should revisit
the whole issue of how partition bound values are parsed for v12.
Amit Langote
Discussion: https://postgr.es/m/e05c5162-1103-7e37-d1ab-6de3e0afaf70@lab.ntt.co.jp
Change things around so that proper quoting of values interpolated into
the BKI data by initdb is the responsibility of initdb, not something
we half-heartedly handle by putting double quotes into the raw BKI data.
(Note: experimentation shows that it still doesn't work to put a double
quote into the initial superuser username, but that's the fault of
inadequate quoting while interpolating the name into SQL scripts;
the BKI aspect of it works fine now.)
Having done that, we can remove the special-case handling of values
that look like "something" from genbki.pl, and instead teach it to
escape double --- and single --- quotes properly. This removes the
nowhere-documented need to treat those specially in the BKI source
data; whatever you write will be passed through unchanged into the
inserted data value, modulo Perl's rules about single-quoted strings.
Add documentation explaining the (pre-existing) handling of backslashes
in the BKI data.
Per an earlier discussion with John Naylor.
Discussion: https://postgr.es/m/CAJVSVGUNao=-Q2-vAN3PYcdF5tnL5JAHwGwzZGuYHtq+Mk_9ng@mail.gmail.com
They were accidentally excluded when reverting the backend online
checksum functionality, and since they weren't built the incorrect
reference to a removed section also did not trigger a problem.
Author: Christoph Berg
Make it clear that a cluster has to be shut down cleanly before
pg_verify_checksum can be run against it.
Author: Michael Paquier
Review: Daniel Gustafsson
This option makes no sense when the cluster checksum state cannot be
changed, and should have been removed in the revert.
Author: Daniel Gustafsson
Review: Michael Paquier
This reverts commits d204ef6377,
83454e3c2b and a few more commits thereafter
(complete list at the end) related to MERGE feature.
While the feature was fully functional, with sufficient test coverage and
necessary documentation, it was felt that some parts of the executor and
parse-analyzer can use a different design and it wasn't possible to do that in
the available time. So it was decided to revert the patch for PG11 and retry
again in the future.
Thanks again to all reviewers and bug reporters.
List of commits reverted, in reverse chronological order:
f1464c5380 Improve parse representation for MERGE
ddb4158579 MERGE syntax diagram correction
530e69e59b Allow cpluspluscheck to pass by renaming variable
01b88b4df5 MERGE minor errata
3af7b2b0d4 MERGE fix variable warning in non-assert builds
a5d86181ec MERGE INSERT allows only one VALUES clause
4b2d44031f MERGE post-commit review
4923550c20 Tab completion for MERGE
aa3faa3c7a WITH support in MERGE
83454e3c2b New files for MERGE
d204ef6377 MERGE SQL Command following SQL:2016
Author: Pavan Deolasee
Reviewed-by: Michael Paquier
In particular, the requirement to have SELECT privilege for the initial
table copy was previously not documented.
Author: Shinoda, Noriyoshi <noriyoshi.shinoda@hpe.com>
Commit 372728b0d created some problems for usages like building a
subdirectory without having first done "make all" at the top level,
or for proceeding directly to "make install" without "make all".
The only reasonably clean way to fix this seems to be to force the
submake-generated-headers rule to fire in *any* "make all" or "make
install" command anywhere in the tree. To avoid lots of redundant work,
as well as parallel make jobs possibly clobbering each others' output, we
still need to be sure that the rule fires only once in a recursive build.
For that, adopt the same MAKELEVEL hack previously used for "temp-install".
But try to document it a bit better.
The submake-errcodes mechanism previously used in src/port/ and src/common/
is subsumed by this, so we can get rid of those special cases. It was
inadequate for src/common/ anyway after the aforesaid commit, and it always
risked parallel attempts to build errcodes.h.
Discussion: https://postgr.es/m/E1f5FAB-0006LU-MB@gemulon.postgresql.org
In its original form, reformat_dat_file.pl smashed consecutive blank
lines to a single blank line, which was helpful for mopping up excess
whitespace during the bootstrap data format conversion. But going
forward, there seems little reason to do that; if developers want to
put in multiple blank lines, let 'em. This makes it conform to the
documentation I (tgl) wrote, too.
In passing, clean up some sloppy markup choices in bki.sgml.
John Naylor
Discussion: https://postgr.es/m/28827.1523039259@sss.pgh.pa.us
This reverts the backend sides of commit 1fde38beaa.
I have, at least for now, left the pg_verify_checksums tool in place, as
this tool can be very valuable without the rest of the patch as well,
and since it's a read-only tool that only runs when the cluster is down
it should be a lot safer.
Historically, the initial catalog data to be installed during bootstrap
has been written in DATA() lines in the catalog header files. This had
lots of disadvantages: the format was badly underdocumented, it was
very difficult to edit the data in any mechanized way, and due to the
lack of any abstraction the data was verbose, hard to read/understand,
and easy to get wrong.
Hence, move this data into separate ".dat" files and represent it in a way
that can easily be read and rewritten by Perl scripts. The new format is
essentially "key => value" for each column; while it's a bit repetitive,
explicit labeling of each value makes the data far more readable and less
error-prone. Provide a way to abbreviate entries by omitting field values
that match a specified default value for their column. This allows removal
of a large amount of repetitive boilerplate and also lowers the barrier to
adding new columns.
Also teach genbki.pl how to translate symbolic OID references into
numeric OIDs for more cases than just "regproc"-like pg_proc references.
It can now do that for regprocedure-like references (thus solving the
problem that regproc is ambiguous for overloaded functions), operators,
types, opfamilies, opclasses, and access methods. Use this to turn
nearly all OID cross-references in the initial data into symbolic form.
This represents a very large step forward in readability and error
resistance of the initial catalog data. It should also reduce the
difficulty of renumbering OID assignments in uncommitted patches.
Also, solve the longstanding problem that frontend code that would like to
use OID macros and other information from the catalog headers often had
difficulty with backend-only code in the headers. To do this, arrange for
all generated macros, plus such other declarations as we deem fit, to be
placed in "derived" header files that are safe for frontend inclusion.
(Once clients migrate to using these pg_*_d.h headers, it will be possible
to get rid of the pg_*_fn.h headers, which only exist to quarantine code
away from clients. That is left for follow-on patches, however.)
The now-automatically-generated macros include the Anum_xxx and Natts_xxx
constants that we used to have to update by hand when adding or removing
catalog columns.
Replace the former manual method of generating OID macros for pg_type
entries with an automatic method, ensuring that all built-in types have
OID macros. (But note that this patch does not change the way that
OID macros for pg_proc entries are built and used. It's not clear that
making that match the other catalogs would be worth extra code churn.)
Add SGML documentation explaining what the new data format is and how to
work with it.
Despite being a very large change in the catalog headers, there is no
catversion bump here, because postgres.bki and related output files
haven't changed at all.
John Naylor, based on ideas from various people; review and minor
additional coding by me; previous review by Alvaro Herrera
Discussion: https://postgr.es/m/CAJVSVGWO48JbbwXkJz_yBFyGYW-M9YWxnPdxJBUosDC9ou_F0Q@mail.gmail.com
This rectifies an oversight in commit 8224de4f4, by adding a new
property 'can_include' for pg_indexam_has_property, and adjusting the
results of pg_index_column_has_property to give more appropriate
results for INCLUDEd columns.
Allow the cluster to be optionally init'd with read access for the
group.
This means a relatively non-privileged user can perform a backup of the
cluster without requiring write privileges, which enhances security.
The mode of PGDATA is used to determine whether group permissions are
enabled for directory and file creates. This method was chosen as it's
simple and works well for the various utilities that write into PGDATA.
Changing the mode of PGDATA manually will not automatically change the
mode of all the files contained therein. If the user would like to
enable group access on an existing cluster then changing the mode of all
the existing files will be required. Note that pg_upgrade will
automatically change the mode of all migrated files if the new cluster
is init'd with the -g option.
Tests are included for the backend and all the utilities which operate
on the PG data directory to ensure that the correct mode is set based on
the data directory permissions.
Author: David Steele <david@pgmasters.net>
Reviewed-By: Michael Paquier, with discussion amongst many others.
Discussion: https://postgr.es/m/ad346fe6-b23e-59f1-ecb7-0e08390ad629%40pgmasters.net
Existing partition pruning is only able to work at plan time, for query
quals that appear in the parsed query. This is good but limiting, as
there can be parameters that appear later that can be usefully used to
further prune partitions.
This commit adds support for pruning subnodes of Append which cannot
possibly contain any matching tuples, during execution, by evaluating
Params to determine the minimum set of subnodes that can possibly match.
We support more than just simple Params in WHERE clauses. Support
additionally includes:
1. Parameterized Nested Loop Joins: The parameter from the outer side of the
join can be used to determine the minimum set of inner side partitions to
scan.
2. Initplans: Once an initplan has been executed we can then determine which
partitions match the value from the initplan.
Partition pruning is performed in two ways. When Params external to the plan
are found to match the partition key we attempt to prune away unneeded Append
subplans during the initialization of the executor. This allows us to bypass
the initialization of non-matching subplans meaning they won't appear in the
EXPLAIN or EXPLAIN ANALYZE output.
For parameters whose value is only known during the actual execution
then the pruning of these subplans must wait. Subplans which are
eliminated during this stage of pruning are still visible in the EXPLAIN
output. In order to determine if pruning has actually taken place, the
EXPLAIN ANALYZE must be viewed. If a certain Append subplan was never
executed due to the elimination of the partition then the execution
timing area will state "(never executed)". Whereas, if, for example in
the case of parameterized nested loops, the number of loops stated in
the EXPLAIN ANALYZE output for certain subplans may appear lower than
others due to the subplan having been scanned fewer times. This is due
to the list of matching subnodes having to be evaluated whenever a
parameter which was found to match the partition key changes.
This commit required some additional infrastructure that permits the
building of a data structure which is able to perform the translation of
the matching partition IDs, as returned by get_matching_partitions, into
the list index of a subpaths list, as exist in node types such as
Append, MergeAppend and ModifyTable. This allows us to translate a list
of clauses into a Bitmapset of all the subpath indexes which must be
included to satisfy the clause list.
Author: David Rowley, based on an earlier effort by Beena Emerson
Reviewers: Amit Langote, Robert Haas, Amul Sul, Rajkumar Raghuwanshi,
Jesper Pedersen
Discussion: https://postgr.es/m/CAOG9ApE16ac-_VVZVvv0gePSgkg_BwYEV1NBqZFqDR2bBE0X0A@mail.gmail.com
This patch introduces INCLUDE clause to index definition. This clause
specifies a list of columns which will be included as a non-key part in
the index. The INCLUDE columns exist solely to allow more queries to
benefit from index-only scans. Also, such columns don't need to have
appropriate operator classes. Expressions are not supported as INCLUDE
columns since they cannot be used in index-only scans.
Index access methods supporting INCLUDE are indicated by amcaninclude flag
in IndexAmRoutine. For now, only B-tree indexes support INCLUDE clause.
In B-tree indexes INCLUDE columns are truncated from pivot index tuples
(tuples located in non-leaf pages and high keys). Therefore, B-tree indexes
now might have variable number of attributes. This patch also provides
generic facility to support that: pivot tuples contain number of their
attributes in t_tid.ip_posid. Free 13th bit of t_info is used for indicating
that. This facility will simplify further support of index suffix truncation.
The changes of above are backward-compatible, pg_upgrade doesn't need special
handling of B-tree indexes for that.
Bump catalog version
Author: Anastasia Lubennikova with contribition by Alexander Korotkov and me
Reviewed by: Peter Geoghegan, Tomas Vondra, Antonin Houska, Jeff Janes,
David Rowley, Alexander Korotkov
Discussion: https://www.postgresql.org/message-id/flat/56168952.4010101@postgrespro.ru
