Commit Graph

918 Commits

Author SHA1 Message Date
Bruce Momjian 87a19eb9bf doc: explain use of json_populate_record{set}()
The set-returning nature of these functions make their use unclear. The
modified paragraph was added in PG 9.4.

Reported-by: yshaladi@denodo.com

Discussion:  https://postgr.es/m/152571684246.9460.18059951267371255159@wrigleys.postgresql.org

Backpatch-through: 9.4
2018-06-19 13:43:40 -04:00
Andrew Gierth 93f6c6328d doc: fix description of backward_scan
The description of the index property backward_scan was incorrect and
misleading; rectify.

Backpatch to 9.6 where the amutils functionality was introduced.
2018-05-17 21:23:48 +01:00
Magnus Hagander a228cc13ae Revert "Allow on-line enabling and disabling of data checksums"
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.
2018-04-09 19:03:42 +02:00
Andrew Gierth 49b0e300f7 Support index INCLUDE in the AM properties interface.
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.
2018-04-08 06:02:05 +01:00
Teodor Sigaev 1c1791e000 Add json(b)_to_tsvector function
Jsonb has a complex nature so there isn't best-for-everything way to convert it
to tsvector for full text search. Current to_tsvector(json(b)) suggests to
convert only string values, but it's possible to index keys, numerics and even
booleans value. To solve that json(b)_to_tsvector has a second required
argument contained a list of desired types of json fields. Second argument is
a jsonb scalar or array right now with possibility to add new options in a
future.

Bump catalog version

Author: Dmitry Dolgov with some editorization by me
Reviewed by: Teodor Sigaev
Discussion: https://www.postgresql.org/message-id/CA+q6zcXJQbS1b4kJ_HeAOoOc=unfnOrUEL=KGgE32QKDww7d8g@mail.gmail.com
2018-04-07 20:58:03 +03:00
Stephen Frost 0fdc8495bf Add default roles for file/program access
This patch adds new default roles named 'pg_read_server_files',
'pg_write_server_files', 'pg_execute_server_program' which
allow an administrator to GRANT to a non-superuser role the ability to
access server-side files or run programs through PostgreSQL (as the user
the database is running as).  Having one of these roles allows a
non-superuser to use server-side COPY to read, write, or with a program,
and to use file_fdw (if installed by a superuser and GRANT'd USAGE on
it) to read from files or run a program.

The existing misc file functions are also changed to allow a user with
the 'pg_read_server_files' default role to read any files on the
filesystem, matching the privileges given to that role through COPY and
file_fdw from above.

Reviewed-By: Michael Paquier
Discussion: https://postgr.es/m/20171231191939.GR2416%40tamriel.snowman.net
2018-04-06 14:47:10 -04:00
Magnus Hagander 1fde38beaa Allow on-line enabling and disabling of data checksums
This makes it possible to turn checksums on in a live cluster, without
the previous need for dump/reload or logical replication (and to turn it
off).

Enabling checkusm starts a background process in the form of a
launcher/worker combination that goes through the entire database and
recalculates checksums on each and every page. Only when all pages have
been checksummed are they fully enabled in the cluster. Any failure of
the process will revert to checksums off and the process has to be
started.

This adds a new WAL record that indicates the state of checksums, so
the process works across replicated clusters.

Authors: Magnus Hagander and Daniel Gustafsson
Review: Tomas Vondra, Michael Banck, Heikki Linnakangas, Andrey Borodin
2018-04-05 22:04:48 +02:00
Teodor Sigaev 1664ae1978 Add websearch_to_tsquery
Error-tolerant conversion function with web-like syntax for search query,
it simplifies  constraining search engine with close to habitual interface for
users.

Bump catalog version

Authors: Victor Drobny, Dmitry Ivanov with editorization by me
Reviewed by: Aleksander Alekseev, Tomas Vondra, Thomas Munro, Aleksandr Parfenov
Discussion: https://www.postgresql.org/message-id/flat/fe931111ff7e9ad79196486ada79e268@postgrespro.ru
2018-04-05 19:55:11 +03:00
Teodor Sigaev 710d90da1f Add prefix operator for TEXT type.
The prefix operator along with SP-GiST indexes can be used as an alternative
for LIKE 'word%' commands  and it doesn't have a limitation of string/prefix
length as B-Tree has.

Bump catalog version

Author: Ildus Kurbangaliev with some editorization by me
Review by: Arthur Zakirov, Alexander Korotkov, and me
Discussion: https://www.postgresql.org/message-id/flat/20180202180327.222b04b3@wp.localdomain
2018-04-03 19:46:45 +03:00
Bruce Momjian 756dca8e7f doc: document "IS NOT DOCUMENT"
Reported-by: scott.ure@caseware.com

Discussion: https://postgr.es/m/152056505045.4963.16783351661813640274@wrigleys.postgresql.org

Author: Euler Taveira

Backpatch-through: 10
2018-03-30 10:39:48 -04:00
Andres Freund fb60478011 Improve JIT docs.
Author: John Naylor and Andres Freund
Discussion: https://postgr.es/m/CAJVSVGUs-VcwSY7-Kx-GQe__8hvWuA4Uhyf3gxoMXeiZqebE9g@mail.gmail.com
2018-03-29 16:13:40 -07:00
Andres Freund e6c039d13e Add documentation for the JIT feature.
As promised in earlier commits, this adds documentation about the new
build options, the new GUCs, about the planner logic when JIT is used,
and the benefits of JIT in general.

Also adds a more implementation oriented README.

I'm sure we're going to want to expand this further, but I think this
is a reasonable start.

Author: Andres Freund, with contributions by Thomas Munro
Reviewed-By: Thomas Munro
Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-03-28 14:22:42 -07:00
Tom Lane ee4a2c4a03 Doc: remove extra comma in syntax summary for array_fill().
Noted by Scott Ure.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/152199346794.4544.1888397173908716912@wrigleys.postgresql.org
2018-03-25 12:38:21 -04:00
Peter Eisentraut 10cfce34c0 Add user-callable SHA-2 functions
Add the user-callable functions sha224, sha256, sha384, sha512.  We
already had these in the C code to support SCRAM, but there was no test
coverage outside of the SCRAM tests.  Adding these as user-callable
functions allows writing some tests.  Also, we have a user-callable md5
function but no more modern alternative, which led to wide use of md5 as
a general-purpose hash function, which leads to occasional complaints
about using md5.

Also mark the existing md5 functions as leak-proof.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-02-22 11:34:53 -05:00
Peter Eisentraut 2ac3e6acc2 doc: pg_function_is_visible also applies to aggregates and procedures 2018-02-13 15:13:44 -05:00
Peter Eisentraut 7a32ac8a66 Add procedure support to pg_get_functiondef
This also makes procedures work in psql's \ef and \sf commands.

Reported-by: Pavel Stehule <pavel.stehule@gmail.com>
2018-02-13 15:13:44 -05:00
Tom Lane 0a459cec96 Support all SQL:2011 options for window frame clauses.
This patch adds the ability to use "RANGE offset PRECEDING/FOLLOWING"
frame boundaries in window functions.  We'd punted on that back in the
original patch to add window functions, because it was not clear how to
do it in a reasonably data-type-extensible fashion.  That problem is
resolved here by adding the ability for btree operator classes to provide
an "in_range" support function that defines how to add or subtract the
RANGE offset value.  Factoring it this way also allows the operator class
to avoid overflow problems near the ends of the datatype's range, if it
wishes to expend effort on that.  (In the committed patch, the integer
opclasses handle that issue, but it did not seem worth the trouble to
avoid overflow failures for datetime types.)

The patch includes in_range support for the integer_ops opfamily
(int2/int4/int8) as well as the standard datetime types.  Support for
other numeric types has been requested, but that seems like suitable
material for a follow-on patch.

In addition, the patch adds GROUPS mode which counts the offset in
ORDER-BY peer groups rather than rows, and it adds the frame_exclusion
options specified by SQL:2011.  As far as I can see, we are now fully
up to spec on window framing options.

Existing behaviors remain unchanged, except that I changed the errcode
for a couple of existing error reports to meet the SQL spec's expectation
that negative "offset" values should be reported as SQLSTATE 22013.

Internally and in relevant parts of the documentation, we now consistently
use the terminology "offset PRECEDING/FOLLOWING" rather than "value
PRECEDING/FOLLOWING", since the term "value" is confusingly vague.

Oliver Ford, reviewed and whacked around some by me

Discussion: https://postgr.es/m/CAGMVOdu9sivPAxbNN0X+q19Sfv9edEPv=HibOJhB14TJv_RCQg@mail.gmail.com
2018-02-07 00:06:56 -05:00
Simon Riggs 9c7d06d606 Ability to advance replication slots
Ability to advance both physical and logical replication slots using a
new user function pg_replication_slot_advance().

For logical advance that means records are consumed as fast as possible
and changes are not given to output plugin for sending. Makes 2nd phase
(after we reached SNAPBUILD_FULL_SNAPSHOT) of replication slot creation
faster, especially when there are big transactions as the reorder buffer
does not have to deal with data changes and does not have to spill to
disk.

Author: Petr Jelinek
Reviewed-by: Simon Riggs
2018-01-17 11:38:34 +00:00
Andrew Dunstan 11b623dd0a Implement TZH and TZM timestamp format patterns
These are compatible with Oracle and required for the datetime template
language for jsonpath in an upcoming patch.

Nikita Glukhov and Andrew Dunstan, reviewed by Pavel Stehule.
2018-01-09 14:25:05 -05:00
Peter Eisentraut 3c49c6facb Convert documentation to DocBook XML
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
2017-11-23 09:44:28 -05:00
Tom Lane 63ca86318d Fix quoted-substring handling in format parsing for to_char/to_number/etc.
This code evidently intended to treat backslash as an escape character
within double-quoted substrings, but it was sufficiently confused that
cases like ..."foo\\"... did not work right: the second backslash
managed to quote the double-quote after it, despite being quoted itself.
Rewrite to get that right, while preserving the existing behavior
outside double-quoted substrings, which is that backslash isn't special
except in the combination \".

Comparing to Oracle, it seems that their version of to_char() for
timestamps allows literal alphanumerics only within double quotes, while
non-alphanumerics are allowed outside quotes; backslashes aren't special
anywhere; there is no way at all to emit a literal double quote.
(Bizarrely, their to_char() for numbers is different; it doesn't allow
literal text at all AFAICT.)  The fact that they don't treat backslash
as special justifies our existing behavior for backslash outside double
quotes.  I considered making backslash inside double quotes act the same
way (ie, special only if before "), which in a green field would be a
more consistent behavior.  But that would likely break more existing SQL
code than what this patch does.

Add some test cases illustrating this behavior.  (Only the last new
case actually changes behavior in this commit.)

Little of this behavior was documented, either, so fix that.

Discussion: https://postgr.es/m/3626.1510949486@sss.pgh.pa.us
2017-11-18 12:16:37 -05:00
Tom Lane e87d4965bd Prevent to_number() from losing data when template doesn't match exactly.
Non-data template patterns would consume characters whether or not those
characters were what the pattern expected, for example
	SELECT TO_NUMBER('1234', '9,999');
produced 134 because the '2' got eaten by the comma pattern.  This seems
undesirable, not least because it doesn't happen in Oracle.  For the ','
and 'G' template patterns, we can fix this by consuming characters only
if they match what the pattern would output.  For non-data patterns such
as 'L' and 'TH', it seems impractical to tighten things up to the point of
consuming only exact matches to what the pattern would output; but we can
improve matters quite a lot by redefining the behavior as "consume only
characters that aren't digits, signs, decimal point, or comma".

Also, fix it so that the behavior is to consume the number of *characters*
the pattern would output, not the number of *bytes*.  The old coding would
do surprising things with non-ASCII currency symbols, for example.  (It
would be good to apply that rule for literal text as well, but this commit
only fixes it for non-data patterns.)

Oliver Ford, reviewed by Thomas Munro and Nathan Wagner, and whacked around
a bit more by me

Discussion: https://postgr.es/m/CAGMVOdvpbMqPf9XWNzOwBpzJfErkydr_fEGhmuDGa015z97mwg@mail.gmail.com
2017-11-17 12:04:13 -05:00
Simon Riggs 4b0d28de06 Remove secondary checkpoint
Previously server reserved WAL for last two checkpoints,
which used too much disk space for small servers.

Bumps PG_CONTROL_VERSION

Author: Simon Riggs <simon@2ndQuadrant.com>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2017-11-07 12:56:30 -05:00
Peter Eisentraut 1ff01b3902 Convert SGML IDs to lower case
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>
2017-10-20 19:26:10 -04:00
Peter Eisentraut c29c578908 Don't use SGML empty tags
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
2017-10-17 15:10:33 -04:00
Peter Eisentraut 44b3230e82 Use lower-case SGML attribute values
for DocBook XML compatibility
2017-10-10 10:15:57 -04:00
Peter Eisentraut 22d9764646 Remove SGML marked sections
For XML compatibility, replace marked sections <![IGNORE[ ]]> with
comments <!-- -->.  In some cases it seemed better to remove the ignored
text altogether, and in one case the text should not have been ignored.
2017-09-28 16:17:28 -04:00
Peter Eisentraut 3012061b86 Apply pg_get_serial_sequence() to identity column sequences as well
Bug: #14813
2017-09-15 14:21:20 -04:00
Tom Lane ce5dcf54b9 Improve docs about numeric formatting patterns (to_char/to_number).
The explanation about "0" versus "9" format characters was confusing
and arguably wrong; the discussion of sign handling wasn't very good
either.  Notably, while it's accurate to say that "FM" strips leading
zeroes in date/time values, what it really does with numeric values
is to strip *trailing* zeroes, and then only if you wrote "9" rather
than "0".  Per gripes from Erwin Brandstetter.

Discussion: https://postgr.es/m/CAGHENJ7jgRbTn6nf48xNZ=FHgL2WQ4X8mYsUAU57f-vq8PubEw@mail.gmail.com
Discussion: https://postgr.es/m/CAGHENJ45ymd=GOCu1vwV9u7GmCR80_5tW0fP9C_gJKbruGMHvQ@mail.gmail.com
2017-08-29 09:34:21 -04:00
Robert Haas 449338cc64 Improve low-level backup documentation.
Our documentation hasn't really caught up with the fact that
non-exclusive backups can now be taken using pg_start_backup and
pg_stop_backup even on standbys.  Update, also correcting some
errors introduced by 52f8a59dd9.
Updates to the 9.6 documentation are needed as well, but that
will need a separate patch as some things are different on that
version.

David Steele, reviewed by Robert Haas and Michael Paquier

Discussion: http://postgr.es/m/d4d951b9-89c0-6bc1-b6ff-d0b2dd5a8966@pgmasters.net
2017-08-25 15:20:27 -04:00
Robert Haas 52f8a59dd9 Make pg_stop_backup's wait_for_archive flag work on standbys.
Previously, it had no effect.  Now, if archive_mode=always, it will
work, and if not, you'll get a warning.

Masahiko Sawada, Michael Paquier, and Robert Haas.  The patch as
submitted also changed the behavior so that we would write and remove
history files on standbys, but that seems like material for a separate
patch to me.

Discussion: http://postgr.es/m/CAD21AoC2Xw6M=ZJyejq_9d_iDkReC_=rpvQRw5QsyzKQdfYpkw@mail.gmail.com
2017-08-05 10:49:26 -04:00
Tom Lane 0b13b2a771 Rethink behavior of pg_import_system_collations().
Marco Atzeri reported that initdb would fail if "locale -a" reported
the same locale name more than once.  All previous versions of Postgres
implicitly de-duplicated the results of "locale -a", but the rewrite
to move the collation import logic into C had lost that property.
It had also lost the property that locale names matching built-in
collation names were silently ignored.

The simplest way to fix this is to make initdb run the function in
if-not-exists mode, which means that there's no real use-case for
non if-not-exists mode; we might as well just drop the boolean argument
and simplify the function's definition to be "add any collations not
already known".  This change also gets rid of some odd corner cases
caused by the fact that aliases were added in if-not-exists mode even
if the function argument said otherwise.

While at it, adjust the behavior so that pg_import_system_collations()
doesn't spew "collation foo already exists, skipping" messages during a
re-run; that's completely unhelpful, especially since there are often
hundreds of them.  And make it return a count of the number of collations
it did add, which seems like it might be helpful.

Also, re-integrate the previous coding's property that it would make a
deterministic selection of which alias to use if there were conflicting
possibilities.  This would only come into play if "locale -a" reports
multiple equivalent locale names, say "de_DE.utf8" and "de_DE.UTF-8",
but that hardly seems out of the question.

In passing, fix incorrect behavior in pg_import_system_collations()'s
ICU code path: it neglected CommandCounterIncrement, which would result
in failures if ICU returns duplicate names, and it would try to create
comments even if a new collation hadn't been created.

Also, reorder operations in initdb so that the 'ucs_basic' collation
is created before calling pg_import_system_collations() not after.
This prevents a failure if "locale -a" were to report a locale named
that.  There's no reason to think that that ever happens in the wild,
but the old coding would have survived it, so let's be equally robust.

Discussion: https://postgr.es/m/20c74bc3-d6ca-243d-1bbc-12f17fa4fe9a@gmail.com
2017-06-23 14:19:58 -04:00
Peter Eisentraut bbaf9e8f84 Documentation spell checking and markup improvements 2017-06-18 14:02:12 -04:00
Peter Eisentraut bf6e4c3c82 Trim trailing whitespace 2017-06-12 09:51:18 -04:00
Tom Lane f04c9a6146 Standardize terminology for pg_statistic_ext entries.
Consistently refer to such an entry as a "statistics object", not just
"statistics" or "extended statistics".  Previously we had a mismash of
terms, accompanied by utter confusion as to whether the term was
singular or plural.  That's not only grating (at least to the ear of
a native English speaker) but could be outright misleading, eg in error
messages that seemed to be referring to multiple objects where only one
could be meant.

This commit fixes the code and a lot of comments (though I may have
missed a few).  I also renamed two new SQL functions,
pg_get_statisticsextdef -> pg_get_statisticsobjdef
pg_statistic_ext_is_visible -> pg_statistics_obj_is_visible
to conform better with this terminology.

I have not touched the SGML docs other than fixing those function
names; the docs certainly need work but it seems like a separable task.

Discussion: https://postgr.es/m/22676.1494557205@sss.pgh.pa.us
2017-05-14 10:55:01 -04:00
Alvaro Herrera d99d58cdc8 Complete tab completion for DROP STATISTICS
Tab-completing DROP STATISTICS would only work if you started writing
the schema name containing the statistics object, because the visibility
clause was missing.  To add it, we need to add SQL-callable support for
testing visibility of a statistics object, like all other object types
already have.

Discussion: https://postgr.es/m/22676.1494557205@sss.pgh.pa.us
2017-05-13 01:05:48 -03:00
Peter Eisentraut 46052d9ef3 Replace another "transaction log" with "write-ahead log"
Reported-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
2017-05-12 13:53:24 -04:00
Peter Eisentraut c1a7f64b4a Replace "transaction log" with "write-ahead log"
This makes documentation and error messages match the renaming of "xlog"
to "wal" in APIs and file naming.
2017-05-12 11:52:43 -04:00
Tom Lane efa2c18f4e Doc fix: scale(numeric) returns integer, not numeric.
Thinko in commit abb173392, which introduced this function.

Report: https://postgr.es/m/20170511215234.1795.54347@wrigleys.postgresql.org
2017-05-11 18:09:22 -04:00
Tom Lane d10c626de4 Rename WAL-related functions and views to use "lsn" not "location".
Per discussion, "location" is a rather vague term that could refer to
multiple concepts.  "LSN" is an unambiguous term for WAL locations and
should be preferred.  Some function names, view column names, and function
output argument names used "lsn" already, but others used "location",
as well as yet other terms such as "wal_position".  Since we've already
renamed a lot of things in this area from "xlog" to "wal" for v10,
we may as well incur a bit more compatibility pain and make these names
all consistent.

David Rowley, minor additional docs hacking by me

Discussion: https://postgr.es/m/CAKJS1f8O0njDKe8ePFQ-LK5-EjwThsDws6ohJ-+c6nWK+oUxtg@mail.gmail.com
2017-05-11 11:49:59 -04:00
Tom Lane a9c6d70435 Document current_role.
This system function has been there a very long time, but somehow escaped
being listed in func.sgml.

Fabien Coelho and Tom Lane

Discussion: https://postgr.es/m/alpine.DEB.2.20.1705061027580.3896@lancre
2017-05-06 14:19:47 -04:00
Alvaro Herrera 73c1748d83 Fix XMLTABLE synopsis, add XMLNAMESPACES example
Add a missing comma in the synopsis after the XMLNAMESPACES clause.
Also, add an example illustrating the use of that clause.

Author: Arjen Nienhuis and Pavel Stěhule
2017-04-13 12:12:23 -03:00
Bruce Momjian 1c1a4726eb docs: Improve window function docs
Specifically, the behavior of general-purpose and statistical aggregates
as window functions was not clearly documented, and terms were
inconsistently used.  Also add docs about the difference between
cume_dist and percent_rank, rather than just the formulas.

Discussion: 20170406214918.GA5757@momjian.us
2017-04-11 10:47:47 -04:00
Tom Lane 511540dadf Move isolationtester's is-blocked query into C code for speed.
Commit 4deb41381 modified isolationtester's query to see whether a
session is blocked to also check for waits occurring in GetSafeSnapshot.
However, it did that in a way that enormously increased the query's
runtime under CLOBBER_CACHE_ALWAYS, causing the buildfarm members
that use that to run about four times slower than before, and in some
cases fail entirely.  To fix, push the entire logic into a dedicated
backend function.  This should actually reduce the CLOBBER_CACHE_ALWAYS
runtime from what it was previously, though I've not checked that.

In passing, expose a SQL function to check for safe-snapshot blockage,
comparable to pg_blocking_pids.  This is more or less free given the
infrastructure built to solve the other problem, so we might as well.

Thomas Munro

Discussion: https://postgr.es/m/20170407165749.pstcakbc637opkax@alap3.anarazel.de
2017-04-10 10:26:54 -04:00
Andrew Dunstan cf35346e81 Make json_populate_record and friends operate recursively
With this change array fields are populated from json(b) arrays, and
composite fields are populated from json(b) objects.

Along the way, some significant code refactoring is done to remove
redundancy in the way to populate_record[_set] and to_record[_set]
functions operate, and some significant efficiency gains are made by
caching tuple descriptors.

Nikita Glukhov, edited some by me.

Reviewed by Aleksander Alekseev and Tom Lane.
2017-04-06 22:22:13 -04:00
Andrew Dunstan e75a78656b Clarify documentation of to_tsvector(json(b))
Per gripe from Sven R. Kunze
2017-04-04 16:50:13 -04:00
Alvaro Herrera c655899ba9 BRIN de-summarization
When the BRIN summary tuple for a page range becomes too "wide" for the
values actually stored in the table (because the tuples that were
present originally are no longer present due to updates or deletes), it
can be useful to remove the outdated summary tuple, so that a future
summarization can install a tighter summary.

This commit introduces a SQL-callable interface to do so.

Author: Álvaro Herrera
Reviewed-by: Eiji Seki
Discussion: https://postgr.es/m/20170228045643.n2ri74ara4fhhfxf@alvherre.pgsql
2017-04-01 16:10:04 -03:00
Alvaro Herrera 7526e10224 BRIN auto-summarization
Previously, only VACUUM would cause a page range to get initially
summarized by BRIN indexes, which for some use cases takes too much time
since the inserts occur.  To avoid the delay, have brininsert request a
summarization run for the previous range as soon as the first tuple is
inserted into the first page of the next range.  Autovacuum is in charge
of processing these requests, after doing all the regular vacuuming/
analyzing work on tables.

This doesn't impose any new tasks on autovacuum, because autovacuum was
already in charge of doing summarizations.  The only actual effect is to
change the timing, i.e. that it occurs earlier.  For this reason, we
don't go any great lengths to record these requests very robustly; if
they are lost because of a server crash or restart, they will happen at
a later time anyway.

Most of the new code here is in autovacuum, which can now be told about
"work items" to process.  This can be used for other things such as GIN
pending list cleaning, perhaps visibility map bit setting, both of which
are currently invoked during vacuum, but do not really depend on vacuum
taking place.

The requests are at the page range level, a granularity for which we did
not have SQL-level access; we only had index-level summarization
requests via brin_summarize_new_values().  It seems reasonable to add
SQL-level access to range-level summarization too, so add a function
brin_summarize_range() to do that.

Authors: Álvaro Herrera, based on sketch from Simon Riggs.
Reviewed-by: Thomas Munro.
Discussion: https://postgr.es/m/20170301045823.vneqdqkmsd4as4ds@alvherre.pgsql
2017-04-01 14:00:53 -03:00
Andrew Dunstan e306df7f9c Full Text Search support for json and jsonb
The new functions are ts_headline() and to_tsvector.

Dmitry Dolgov, edited and documented by me.
2017-03-31 14:26:03 -04:00
Simon Riggs 25fff40798 Default monitoring roles
Three nologin roles with non-overlapping privs are created by default
* pg_read_all_settings - read all GUCs.
* pg_read_all_stats - pg_stat_*, pg_database_size(), pg_tablespace_size()
* pg_stat_scan_tables - may lock/scan tables

Top level role - pg_monitor includes all of the above by default, plus others

Author: Dave Page
Reviewed-by: Stephen Frost, Robert Haas, Peter Eisentraut, Simon Riggs
2017-03-30 14:18:53 -04:00