When dealing with partitioned tables, counters for partitioned tables
are not updated when modifying child tables. This means autoanalyze may
not update optimizer statistics for the parent relations, which can
result in poor plans for some queries.
It's worth documenting this limitation, so that people are aware of it
and can take steps to mitigate it (e.g. by setting up a script executing
ANALYZE regularly).
Backpatch to v10. Older branches are affected too, of couse, but we no
longer maintain those.
Author: Justin Pryzby
Reviewed-by: Zhihong Yu, Tomas Vondra
Backpatch-through: 10
Discussion: https://postgr.es/m/20210913035409.GA10647%40telsasoft.com
This reverts the following commits:
1b5617eb84 Describe (auto-)analyze behavior for partitioned tables
0e69f705cc Set pg_class.reltuples for partitioned tables
41badeaba8 Document ANALYZE storage parameters for partitioned tables
0827e8af70 autovacuum: handle analyze for partitioned tables
There are efficiency issues in this code when handling databases with
large numbers of partitions, and it doesn't look like there isn't any
trivial way to handle those. There are some other issues as well. It's
now too late in the cycle for nontrivial fixes, so we'll have to let
Postgres 14 users continue to manually deal with ANALYZE their
partitioned tables, and hopefully we can fix the issues for Postgres 15.
I kept [most of] be280cdad2 ("Don't reset relhasindex for partitioned
tables on ANALYZE") because while we added it due to 0827e8af70, it is
a good bugfix in its own right, since it affects manual analyze as well
as autovacuum-induced analyze, and there's no reason to revert it.
I retained the addition of relkind 'p' to tables included by
pg_stat_user_tables, because reverting that would require a catversion
bump.
Also, in pg14 only, I keep a struct member that was added to
PgStat_TabStatEntry to avoid breaking compatibility with existing stat
files.
Backpatch to 14.
Discussion: https://postgr.es/m/20210722205458.f2bug3z6qzxzpx2s@alap3.anarazel.de
Previously, the only place where progress reports were mentioned is in
the section for monitoring dedicated to its catalogs. This makes the
progress reporting more discoverable, by adding links from the pages of
the commands supporting progress reports to their related catalog
views.
Author: Matthias van de Meent
Reviewed-by: Justin Pryzby, Bharath Rupireddy, Josef Šimánek, Tomas
Vondra
Discussion: https://postgr.es/m/CAEze2WiOcgdH4aQA8NtZq-4dgvnJzp8PohdeKchPkhMY-jWZXA@mail.gmail.com
SQL commands are generally marked up as <command>, except when a link
to a reference page is used using <xref>. But the latter doesn't
create monospace markup, so this looks strange especially when a
paragraph contains a mix of links and non-links.
We considered putting <command> in the <refentrytitle> on the target
side, but that creates some formatting side effects elsewhere.
Generally, it seems safer to solve this on the link source side.
We can't put the <xref> inside the <command>; the DTD doesn't allow
this. DocBook 5 would allow the <command> to have the linkend
attribute itself, but we are not there yet.
So to solve this for now, convert the <xref>s to <link> plus
<command>. This gives the correct look and also gives some more
flexibility what we can put into the link text (e.g., subcommands or
other clauses). In the future, these could then be converted to
DocBook 5 style.
I haven't converted absolutely all xrefs to SQL command reference
pages, only those where we care about the appearance of the link text
or where it was otherwise appropriate to make the appearance match a
bit better. Also in some cases, the links where repetitive, so in
those cases the links where just removed and replaced by a plain
<command>. In cases where we just want the link and don't
specifically care about the generated link text (typically phrased
"for further information see <xref ...>") the xref is kept.
Reported-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/87o8pco34z.fsf@wibble.ilmari.org
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 41b54ba78e allowed not only VACUUM but also ANALYZE options
to take a boolean argument. But it forgot to update the documentation
for ANALYZE. This commit adds the descriptions about those ANALYZE
boolean options into the documentation.
This patch also updates tab-completion for ANALYZE boolean options.
Reported-by: Kyotaro Horiguchi
Author: Fujii Masao
Reviewed-by: Masahiko Sawada, Michael Paquier
Discussion: https://postgr.es/m/CAHGQGwHTUt-kuwgiwe8f0AvTnB+ySqJWh95jvmh-qcoKW9YA9g@mail.gmail.com
When specified, this option allows VACUUM to skip the work on a relation
if there is a conflicting lock on it when trying to open it at the
beginning of its processing.
Similarly to autovacuum, this comes with a couple of limitations while
the relation is processed which can cause the process to still block:
- when opening the relation indexes.
- when acquiring row samples for table inheritance trees, partition trees
or certain types of foreign tables, and that a lock is taken on some
leaves of such trees.
Author: Nathan Bossart
Reviewed-by: Michael Paquier, Andres Freund, Masahiko Sawada
Discussion: https://postgr.es/m/9EF7EBE4-720D-4CF1-9D0E-4403D7E92990@amazon.com
Discussion: https://postgr.es/m/20171201160907.27110.74730@wrigleys.postgresql.org
This is analogous to the syntax allowed for VACUUM. This allows us to
avoid making new options reserved keywords and makes it easier to
allow arbitrary argument order. Oh, and it's consistent with the other
commands, too.
Author: Nathan Bossart
Reviewed-By: Michael Paquier, Masahiko Sawada
Discussion: https://postgr.es/m/D3FC73E2-9B1A-4DB4-8180-55F57D116B4E@amazon.com
Since some preparation work had already been done, the only source
changes left were changing empty-element tags like <xref linkend="foo">
to <xref linkend="foo"/>, and changing the DOCTYPE.
The source files are still named *.sgml, but they are actually XML files
now. Renaming could be considered later.
In the build system, the intermediate step to convert from SGML to XML
is removed. Everything is build straight from the source files again.
The OpenSP (or the old SP) package is no longer needed.
The documentation toolchain instructions are updated and are much
simpler now.
Peter Eisentraut, Alexander Lakhin, Jürgen Purtz
IDs in SGML are case insensitive, and we have accumulated a mix of upper
and lower case IDs, including different variants of the same ID. In
XML, these will be case sensitive, so we need to fix up those
differences. Going to all lower case seems most straightforward, and
the current build process already makes all anchors and lower case
anyway during the SGML->XML conversion, so this doesn't create any
difference in the output right now. A future XML-only build process
would, however, maintain any mixed case ID spellings in the output, so
that is another reason to clean this up beforehand.
Author: Alexander Lakhin <exclusion@gmail.com>
For DocBook XML compatibility, don't use SGML empty tags (</>) anymore,
replace by the full tag name. Add a warning option to catch future
occurrences.
Alexander Lakhin, Jürgen Purtz
Not much to say about this; does what it says on the tin.
However, formerly, if there was a column list then the ANALYZE action was
implied; now it must be specified, or you get an error. This is because
it would otherwise be a bit unclear what the user meant if some tables
have column lists and some don't.
Nathan Bossart, reviewed by Michael Paquier and Masahiko Sawada, with some
editorialization by me
Discussion: https://postgr.es/m/E061A8E3-5E3D-494D-94F0-E8A9B312BBFC@amazon.com
Also, recursively perform VACUUM and ANALYZE on partitions when the
command is applied to a partitioned table. In passing, some related
documentation updates.
Amit Langote, reviewed by Michael Paquier, Ashutosh Bapat, and by me.
Discussion: http://postgr.es/m/47288cf1-f72c-dfc2-5ff0-4af962ae5c1b@lab.ntt.co.jp
Foreign tables can now be inheritance children, or parents. Much of the
system was already ready for this, but we had to fix a few things of
course, mostly in the area of planner and executor handling of row locks.
As side effects of this, allow foreign tables to have NOT VALID CHECK
constraints (and hence to accept ALTER ... VALIDATE CONSTRAINT), and to
accept ALTER SET STORAGE and ALTER SET WITH/WITHOUT OIDS. Continuing to
disallow these things would've required bizarre and inconsistent special
cases in inheritance behavior. Since foreign tables don't enforce CHECK
constraints anyway, a NOT VALID one is a complete no-op, but that doesn't
mean we shouldn't allow it. And it's possible that some FDWs might have
use for SET STORAGE or SET WITH OIDS, though doubtless they will be no-ops
for most.
An additional change in support of this is that when a ModifyTable node
has multiple target tables, they will all now be explicitly identified
in EXPLAIN output, for example:
Update on pt1 (cost=0.00..321.05 rows=3541 width=46)
Update on pt1
Foreign Update on ft1
Foreign Update on ft2
Update on child3
-> Seq Scan on pt1 (cost=0.00..0.00 rows=1 width=46)
-> Foreign Scan on ft1 (cost=100.00..148.03 rows=1170 width=46)
-> Foreign Scan on ft2 (cost=100.00..148.03 rows=1170 width=46)
-> Seq Scan on child3 (cost=0.00..25.00 rows=1200 width=46)
This was done mainly to provide an unambiguous place to attach "Remote SQL"
fields, but it is useful for inherited updates even when no foreign tables
are involved.
Shigeru Hanada and Etsuro Fujita, reviewed by Ashutosh Bapat and Kyotaro
Horiguchi, some additional hacking by me
DocBook XML is superficially compatible with DocBook SGML but has a
slightly stricter DTD that we have been violating in a few cases.
Although XSLT doesn't care whether the document is valid, the style
sheets don't necessarily process invalid documents correctly, so we need
to work toward fixing this.
This first commit moves the indexterms in refentry elements to an
allowed position. It has no impact on the output.
ANALYZE now accepts foreign tables and allows the table's FDW to control
how the sample rows are collected. (But only manual ANALYZEs will touch
foreign tables, for the moment, since among other things it's not very
clear how to handle remote permissions checks in an auto-analyze.)
contrib/file_fdw is extended to support this.
Etsuro Fujita, reviewed by Shigeru Hanada, some further tweaking by me.
I've made a significant effort at filling in the "Using EXPLAIN" section
to be reasonably complete about mentioning everything that EXPLAIN can
output, including the "Rows Removed" outputs that were added by Marko
Tiikkaja's recent documentation-free patch. I also updated the examples to
be consistent with current behavior; several of them were not close to what
the current code will do. No doubt there's more that can be done here, but
I'm out of patience for today.
In particular, note that autovacuum does not yet understand that it might
need to vacuum inheritance parents as a result of changes to the child
tables.
The endterm attribute is mainly useful when the toolchain does not support
automatic link target text generation for a particular situation. In the
past, this was required by the man page tools for all reference page links,
but that is no longer the case, and it now actually gets in the way of
proper automatic link text generation. The only remaining use cases are
currently xrefs to refsects.
Attributes can now have options, just as relations and tablespaces do, and
the reloptions code is used to parse, validate, and store them. For
simplicity and because these options are not performance critical, we store
them in a separate cache rather than the main relcache.
Thanks to Alex Hunsaker for the review.
This switches the man page building process to use the DocBook XSL stylesheet
toolchain. The previous targets for Docbook2X are removed. configure has been
updated to look for the new tools. The Documentation appendix contains the
new build instructions. There are also a few isolated tweaks in the
documentation to improve places that came out strangely in the man pages.
another section if required by the platform (instead of the old way of
building them in section "l" and always transforming them to the
platform-specific section).
This speeds up the installation on common platforms, and it avoids some
funny business with the man page tools and build process.
parentheses in syntax descriptions. Consistently use the present tense
when describing the basic purpose of each "DROP" command. Add a few
more hyperlinks.
Standard English uses "may", "can", and "might" in different ways:
may - permission, "You may borrow my rake."
can - ability, "I can lift that log."
might - possibility, "It might rain today."
Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice. Similarly, "It may crash" is better stated, "It might crash".
including:
- replacing all the appropriate usages of <citetitle>PostgreSQL
...</citetitle> with &cite-user;, &cite-admin;, and so on
- fix an omission in the EXECUTE documentation
- add some more text to the EXPLAIN documentation
- improve the PL/PgSQL RETURN NEXT documentation (more work to do here)
- minor markup fixes
Neil Conway
attstattarget to indicate 'use the default'. The default is now a GUC
variable default_statistics_target, and so may be changed on the fly. Along
the way we gain the ability to have pg_dump dump the per-column statistics
target when it's not the default. Patch by Neil Conway, with some kibitzing
from Tom Lane.
capabilities of specifying time zones as intervals per SQL9x.
Put refentrytitle contents on the same line as the tag.
Otherwise, leading whitespace is propagated into the product, which
(at least) messes up the ToC layout.
Remove (some) docinfo tags containing dates. Best to omit if the dates
are not accurate; maybe use CVS dates instead or leave them out.
Daniel Gustafsson
Tomas Vondra
Alvaro Herrera
David Rowley
Michael Paquier
Peter Eisentraut
Tom Lane
Fujii Masao
Andres Freund
Peter Eisentraut
Robert Haas
Magnus Hagander
Neil Conway
Bruce Momjian
PostgreSQL Daemon
Thomas G. Lockhart