This adds to database objects the same version tracking that collation
objects have. There is a new pg_database column datcollversion that
stores the version, a new function
pg_database_collation_actual_version() to get the version from the
operating system, and a new subcommand ALTER DATABASE ... REFRESH
COLLATION VERSION.
This was not originally added together with pg_collation.collversion,
since originally version tracking was only supported for ICU, and ICU
on a database-level is not currently supported. But we now have
version tracking for glibc (since PG13), FreeBSD (since PG14), and
Windows (since PG13), so this is useful to have now.
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/f0ff3190-29a3-5b39-a179-fa32eee57db6%40enterprisedb.com
The behavior I proposed, of matching case only when only keywords
are available to complete, turns out to be too cute. It adds about
as many problems as it removes. Simplify down to ilmari's original
proposal of just always matching case when completing a keyword.
Also, I noticed while testing this that we've pessimized the behavior
for qualified GUC names: the code is insisting that they be
double-quoted, which was not the case before. Fix that by treating
GUC names as verbatim matches instead of possibly-schema-qualified
names. (While it's tempting to try to split qualified GUC names
so that we *could* treat them with the schema-qualified-name code
path, that really isn't going to work in light of guc.c's willingness
to allow more than two name components.)
Dagfinn Ilmari Mannsåker and Tom Lane
Discussion: https://postgr.es/m/445692.1644018081@sss.pgh.pa.us
The comment for PGAC_READLINE_VARIABLES says "Readline versions < 2.1
don't have rl_completion_append_character". It seems certain that such
versions are extinct in the wild, though; for sure there are none in the
buildfarm. Libedit has had this variable for at least twenty years too.
Also, tab-complete.c's behavior without it is quite unfriendly, since
we'll emit a space even when completion fails; but we've had no
complaints about that.
Therefore, let's assume this variable is always there, and drop the
configure check to save a few build cycles.
Discussion: https://postgr.es/m/147685.1643858911@sss.pgh.pa.us
When completing keywords that are offered alongside names obtained
from a query, preserve the user's choice of keyword case. This
would have been messy to do before 02b8048ba, but now it's fairly
simple. A complication is that we want keywords to be shown in
upper case in any tab-completion menus that include both keywords
and non-keywords, so we can't switch their case until enough has
been typed that only keyword(s) remain to be chosen.
Also, adjust some places where 02b8048ba thoughtlessly held over
a previous choice to display keywords in lower case. (I think
I got confused as to whether those words were keywords or variable
names, but they're the former.)
Dagfinn Ilmari Mannsåker and Tom Lane
Discussion: https://postgr.es/m/8735l41ynm.fsf@wibble.ilmari.org
This patch improves tab completion's ability to deal with
valid variant spellings of SQL identifiers. Notably:
* Unquoted upper-case identifiers are now downcased as the backend
would do, allowing them to be completed correctly.
* Tab completion can now match identifiers that are quoted even
though they don't need to be; for example "f<TAB> now completes
to "foo" if that's the only available name. Previously, only
names that require quotes would be offered.
* Schema-qualified identifiers are now supported where SQL syntax
allows it; many lesser-used completion rules neglected this.
* Completion operations that refer back to some previously-typed
name (for example, to complete names of columns belonging to a
previously-mentioned table) now allow variant spellings of the
previous name too.
In addition, performance of tab completion queries has been
improved for databases containing many objects, although
you'd only be likely to notice with a heavily-loaded server.
Authors of future tab-completion patches should note that this
commit changes many details about how tab completion queries
must be written:
* Tab completion queries now deal in raw object names; do not
use quote_ident().
* The name-matching restriction in a query must now be written
as "outputcol LIKE '%s'", not "substring(outputcol,1,%d)='%s'".
* The SchemaQuery mechanism has been extended so that it can
handle queries that refer back to a previous name. Most completion
queries that do that should be converted to SchemaQuery form.
Only consider using a literal query if the previous name can
never be schema-qualified. Don't use a literal query if the
name-to-be-completed can validly be schema-qualified, either.
* Use set_completion_reference() to specify which word is the previous
name to consider, for either a SchemaQuery or a literal query.
* If you want to offer some keywords in addition to a query result
(for example, offer COLUMN in addition to column names after
"ALTER TABLE t RENAME"), do not use the old hack of tacking the
keywords on with UNION. Instead use the new QUERY_PLUS macros
to write such keywords separately from the query proper. The
"addon" macro arguments that used to be used for this purpose
are gone.
* If your query returns something that's not a SQL identifier
(such as an attribute number or enum label), use the new
QUERY_VERBATIM macros to prevent the result from incorrectly
getting double-quoted. You may still need to use quote_literal
in such a query, too.
Tom Lane and Haiying Tang
Discussion: https://postgr.es/m/a63cbd45e3884cf9b3961c2a6a95dcb7@G08CNEXMBPEKD05.g08.fujitsu.local
Commit 9a974cbcba arranged to preserve
relfilenodes and tablespace OIDs. For similar reasons, also arrange
to preserve database OIDs.
One problem is that, up until now, the OIDs assigned to the template0
and postgres databases have not been fixed. This could be a problem
when upgrading, because pg_upgrade might try to migrate a database
from the old cluster to the new cluster while keeping the OID and find
a different database with that OID, resulting in a failure. If it finds
a database with the same name and the same OID that's OK: it will be
dropped and recreated. But the same OID and a different name is a
problem.
To prevent that, fix the OIDs for postgres and template0 to specific
values less than 16384. To avoid running afoul of this rule, these
values should not be changed in future releases. It's not a problem
that these OIDs aren't fixed in existing releases, because the OIDs
that we're assigning here weren't used for either of these databases
in any previous release. Thus, there's no chance that an upgrade of
a cluster from any previous release will collide with the OIDs we're
assigning here. And going forward, the OIDs will always be fixed, so
the only potential collision is with a system database having the
same name and the same OID, which is OK.
This patch lets users assign a specific OID to a database as well,
provided however that it can't be less than 16384. I (rhaas) thought
it might be better not to expose this capability to users, but the
consensus was otherwise, so the syntax is documented. Letting users
assign OIDs below 16384 would not be OK, though, because a
user-created database with a low-numbered OID might collide with a
system-created database in a future release. We therefore prohibit
that.
Shruthi KC, based on an earlier patch from Antonin Houska, reviewed
and with some adjustments by me.
Discussion: http://postgr.es/m/CA+TgmoYgTwYcUmB=e8+hRHOFA0kkS6Kde85+UNdon6q7bt1niQ@mail.gmail.com
Discussion: http://postgr.es/m/CAASxf_Mnwm1Dh2vd5FAhVX6S1nwNSZUB1z12VddYtM++H2+p7w@mail.gmail.com
Since enum labels have to be single-quoted, this part of the
tab completion machinery got side-swiped by commit cd69ec66c.
A side-effect of that commit is that (at least with some versions
of Readline) the text string passed for completion will omit the
leading quote mark of the enum label literal. Libedit still acts
the same as before, though, so adapt COMPLETE_WITH_ENUM_VALUE so
that it can cope with either convention.
Also, when we fail to find any valid completion, set
rl_completion_suppress_quote = 1. Otherwise readline will
go ahead and append a closing quote, which is unwanted.
Per report from Peter Eisentraut. Back-patch to v13 where
cd69ec66c came in.
Discussion: https://postgr.es/m/8ca82d89-ec3d-8b28-8291-500efaf23b25@enterprisedb.com
Improve psql so that "ALTER TABLE foo VALIDATE CONSTRAINT <TAB>"
only offers not-convalidated entries. While it's not formally
wrong to offer validated ones, there's not much point either,
and it can save some typing if we incorporate this knowledge.
David Fetter, reviewed by Aleksander Alekseev
Discussion: https://postgr.es/m/20210427002433.GB17834@fetter.org
Per discussion, we'll limit support for old servers to those branches
that can still be built easily on modern platforms, which as of now
is 9.2 and up.
Aside from removing code that is dead per the assumption of
server >= 9.2, I tweaked the startup warning for unsupported versions
to complain about too-old servers as well as too-new ones. The
warning that "Some psql features might not work" applies precisely
to both cases.
Discussion: https://postgr.es/m/2923349.1634942313@sss.pgh.pa.us
The following improvements are done:
- Addition of type completion for ALTER SEQUENCE AS.
- Ignore ALTER for transforms, as the command is not supported.
- Addition of more completion for ALTER FOREIGN DATA WRAPPER.
- Addition of options related to columns in ALTER VIEW.
This is a continuation of the work done in 0cd6d3b.
Author: Ken Kato
Discussion: https://postgr.es/m/9497ae9ca1b31eb9b1e97aded1c2ab07@oss.nttdata.com
The following improvements are done:
- Addition of some tab completion for CREATE DOMAIN.
- Addition of some tab completion for CREATE TRANSFORM.
- Addition of type completion for CREATE SEQUENCE AS.
Author: Ken Kato
Reviewed-by: Kyotaro Horiguchi, Michael Paquier
Discussion: https://postgr.es/m/8d370135aef066659eef8e8fbfa6315b@oss.nttdata.com
Completion is added for more object types, like domain constraints, text
search-ish objects or policies. Moreover, the area is reorganized,
changing the list of objects supported by COMMENT to be in the same
order as the documentation to ease future additions.
Author: Ken Kato
Reviewed-by: Fujii Masao, Shinya Kato, Suraj Khamkar, Michael Paquier
Discussion: https://postgr.es/m/6e0c2f3f657b229bea32d098d118f307@oss.nttdata.com
A new option "FOR ALL TABLES IN SCHEMA" in Create/Alter Publication allows
one or more schemas to be specified, whose tables are selected by the
publisher for sending the data to the subscriber.
The new syntax allows specifying both the tables and schemas. For example:
CREATE PUBLICATION pub1 FOR TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;
OR
ALTER PUBLICATION pub1 ADD TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;
A new system table "pg_publication_namespace" has been added, to maintain
the schemas that the user wants to publish through the publication.
Modified the output plugin (pgoutput) to publish the changes if the
relation is part of schema publication.
Updates pg_dump to identify and dump schema publications. Updates the \d
family of commands to display schema publications and \dRp+ variant will
now display associated schemas if any.
Author: Vignesh C, Hou Zhijie, Amit Kapila
Syntax-Suggested-by: Tom Lane, Alvaro Herrera
Reviewed-by: Greg Nancarrow, Masahiko Sawada, Hou Zhijie, Amit Kapila, Haiying Tang, Ajin Cherian, Rahila Syed, Bharath Rupireddy, Mark Dilger
Tested-by: Haiying Tang
Discussion: https://www.postgresql.org/message-id/CALDaNm0OANxuJ6RXqwZsM1MSY4s19nuH3734j4a72etDwvBETQ@mail.gmail.com
Various psql backslash commands have both single-letter and long
forms, for example \e and \edit. Previously, tab completion
generally offered the single-letter form but not the long form.
It seems more sensible to offer the long form, because (a) no
useful completion can happen when you've already typed the single
letter, and (b) if you're not so familiar with the command set
as to know that, the long form is likely to be less confusing.
Haiying Tang, reviewed by Dagfinn Ilmari Mannsåker and myself
Discussion: https://postgr.es/m/OS0PR01MB61136018064660F095CB57A8FB129@OS0PR01MB6113.jpnprd01.prod.outlook.com
This includes the detection of new patterns for various constraint
types, with the addition of USING INDEX for unique indexes of a table
on primary keys and unique constraints.
Author: Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/87bl6ehhpl.fsf@wibble.ilmari.org
The current refresh behavior tries to just refresh added/dropped
publications but that leads to removing wrong tables from subscription. We
can't refresh just the dropped publication because it is quite possible
that some of the tables are removed from publication by that time and now
those will remain as part of the subscription. Also, there is a chance
that the tables that were part of the publication being dropped are also
part of another publication, so we can't remove those.
So, we decided that by default, add/drop commands will also act like
REFRESH PUBLICATION which means they will refresh all the publications. We
can keep the old behavior for "add publication" but it is better to be
consistent with "drop publication".
Author: Hou Zhijie
Reviewed-by: Masahiko Sawada, Amit Kapila
Backpatch-through: 14, where it was introduced
Discussion: https://postgr.es/m/OS0PR01MB5716935D4C2CC85A6143073F94EF9@OS0PR01MB5716.jpnprd01.prod.outlook.com
The logic used to support a change of access method for a table is
similar to changes for tablespace or relation persistence, requiring a
table rewrite with an exclusive lock of the relation changed. Table
rewrites done in ALTER TABLE already go through the table AM layer when
scanning tuples from the old relation and inserting them into the new
one, making this implementation straight-forward.
Note that partitioned tables are not supported as these have no access
methods defined.
Author: Justin Pryzby, Jeff Davis
Reviewed-by: Michael Paquier, Vignesh C
Discussion: https://postgr.es/m/20210228222530.GD20769@telsasoft.com
To add support for streaming transactions at prepare time into the
built-in logical replication, we need to do the following things:
* Modify the output plugin (pgoutput) to implement the new two-phase API
callbacks, by leveraging the extended replication protocol.
* Modify the replication apply worker, to properly handle two-phase
transactions by replaying them on prepare.
* Add a new SUBSCRIPTION option "two_phase" to allow users to enable
two-phase transactions. We enable the two_phase once the initial data sync
is over.
We however must explicitly disable replication of two-phase transactions
during replication slot creation, even if the plugin supports it. We
don't need to replicate the changes accumulated during this phase,
and moreover, we don't have a replication connection open so we don't know
where to send the data anyway.
The streaming option is not allowed with this new two_phase option. This
can be done as a separate patch.
We don't allow to toggle two_phase option of a subscription because it can
lead to an inconsistent replica. For the same reason, we don't allow to
refresh the publication once the two_phase is enabled for a subscription
unless copy_data option is false.
Author: Peter Smith, Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Sawada Masahiko, Vignesh C, Dilip Kumar, Takamichi Osumi, Greg Nancarrow
Tested-By: Haiying Tang
Discussion: https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ru
Discussion: https://postgr.es/m/CAA4eK1+opiV4aFTmWWUF9h_32=HfPOW9vZASHarT0UA5oBrtGw@mail.gmail.com
ALTER SUBSCRIPTION DROP PUBLICATION does not actually support
copy_data option, so remove it from tab completion.
Also, reword the error message that is thrown when all the
publications from a subscription are specified to be dropped.
Also, made few doc and cosmetic adjustments.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddy@enterprisedb.com>
Reviewed-by: Japin Li <japinli@hotmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CALDaNm21RwsDzs4xj14ApteAF7auyyomHNnp+NEL-sH8m-jMvQ@mail.gmail.com
Generalize the INDEX_CLEANUP VACUUM parameter (and the corresponding
reloption): make it into a ternary style boolean parameter. It now
exposes a third option, "auto". The "auto" option (which is now the
default) enables the "bypass index vacuuming" optimization added by
commit 1e55e7d1.
"VACUUM (INDEX_CLEANUP TRUE)" is redefined to once again make VACUUM
simply do any required index vacuuming, regardless of how few dead
tuples are encountered during the first scan of the target heap relation
(unless there are exactly zero). This gives users a way of opting out
of the "bypass index vacuuming" optimization, if for whatever reason
that proves necessary. It is also expected to be used by PostgreSQL
developers as a testing option from time to time.
"VACUUM (INDEX_CLEANUP FALSE)" does the same thing as it always has: it
forcibly disables both index vacuuming and index cleanup. It's not
expected to be used much in PostgreSQL 14. The failsafe mechanism added
by commit 1e55e7d1 addresses the same problem in a simpler way.
INDEX_CLEANUP can now be thought of as a testing and compatibility
option.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-By: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/CAH2-WznrBoCST4_Gxh_G9hA8NzGUbeBGnOUC8FcXcrhqsv6OHQ@mail.gmail.com
An incorrectly-encoded multibyte character near the end of a string
could cause various processing loops to run past the string's
terminating NUL, with results ranging from no detectable issue to
a program crash, depending on what happens to be in the following
memory.
This isn't an issue in the server, because we take care to verify
the encoding of strings before doing any interesting processing
on them. However, that lack of care leaked into client-side code
which shouldn't assume that anyone has validated the encoding of
its input.
Although this is certainly a bug worth fixing, the PG security team
elected not to regard it as a security issue, primarily because
any untrusted text should be sanitized by PQescapeLiteral or
the like before being incorporated into a SQL or psql command.
(If an app fails to do so, the same technique can be used to
cause SQL injection, with probably much more dire consequences
than a mere client-program crash.) Those functions were already
made proof against this class of problem, cf CVE-2006-2313.
To fix, invent PQmblenBounded() which is like PQmblen() except it
won't return more than the number of bytes remaining in the string.
In HEAD we can make this a new libpq function, as PQmblen() is.
It seems imprudent to change libpq's API in stable branches though,
so in the back branches define PQmblenBounded as a macro in the files
that need it. (Note that just changing PQmblen's behavior would not
be a good idea; notably, it would completely break the escaping
functions' defense against this exact problem. So we just want a
version for those callers that don't have any better way of handling
this issue.)
Per private report from houjingyi. Back-patch to all supported branches.
When specified directly as DML queries, INSERT was not getting always
completed to "INSERT INTO", same for DELETE with "DELETE FROM". This
makes the completion behavior more consistent for both commands, saving
a few keystrokes.
Commands on policies, triggers, grant/revoke, etc. require only DELETE
as completion keyword.
Author: Haiying Tang
Reviewed-by: Dilip Kumar, Julien Rouhaud
Discussion: https://postgr.es/m/OS0PR01MB61135AE2B07CCD1AB8C6A0F6FB549@OS0PR01MB6113.jpnprd01.prod.outlook.com
Also "make reformat-dat-files".
The only change worthy of note is that pgindent messed up the formatting
of launcher.c's struct LogicalRepWorkerId, which led me to notice that
that struct wasn't used at all anymore, so I just took it out.
Design problems were discovered in the handling of composite types and
record types that would cause some relevant versions not to be recorded.
Misgivings were also expressed about the use of the pg_depend catalog
for this purpose. We're out of time for this release so we'll revert
and try again.
Commits reverted:
1bf946bd: Doc: Document known problem with Windows collation versions.
cf002008: Remove no-longer-relevant test case.
ef387bed: Fix bogus collation-version-recording logic.
0fb0a050: Hide internal error for pg_collation_actual_version(<bad OID>).
ff942057: Suppress "warning: variable 'collcollate' set but not used".
d50e3b1f: Fix assertion in collation version lookup.
f24b1569: Rethink extraction of collation dependencies.
257836a7: Track collation versions for indexes.
cd6f479e: Add pg_depend.refobjversion.
7d1297df: Remove pg_collation.collversion.
Discussion: https://postgr.es/m/CA%2BhUKGLhj5t1fcjqAu8iD9B3ixJtsTNqyCCD4V0aTO9kAKAjjA%40mail.gmail.com
Commit 8ff1c94649 extended TRUNCATE command so that it can also truncate
foreign tables. But it forgot to support tab-complete for TRUNCATE on
foreign tables. That is, previously tab-complete for TRUNCATE displayed
only the names of regular tables.
This commit improves tab-complete for TRUNCATE so that it displays also
the names of foreign tables.
Author: Fujii Masao
Reviewed-by: Bharath Rupireddy
Discussion: https://postgr.es/m/551ed8c1-f531-818b-664a-2cecdab99cd8@oss.nttdata.com
Documentation and comments in code and tests have been using the terms
sensitive/insensitive cursor incorrectly relative to the SQL standard.
(Cursor sensitivity is only relevant for changes made in the same
transaction as the cursor, not for concurrent changes in other
sessions.) Moreover, some of the behavior of PostgreSQL is incorrect
according to the SQL standard, confusing the issue further. (WHERE
CURRENT OF changes are not visible in insensitive cursors, but they
should be.)
This change corrects the terminology and removes the claim that
sensitive cursors are supported. It also adds a test case that checks
the insensitive behavior in a "correct" way, using a change command
not using WHERE CURRENT OF. Finally, it adds the ASENSITIVE cursor
option to select the default asensitive behavior, per SQL standard.
There are no changes to cursor behavior in this patch.
Discussion: https://www.postgresql.org/message-id/flat/96ee8b30-9889-9e1b-b053-90e10c050e85%40enterprisedb.com
Previously, psql printed only the last result if a command string
returned multiple result sets. Now it prints all of them. The
previous behavior can be obtained by setting the psql variable
SHOW_ALL_RESULTS to off.
Author: Fabien COELHO <coelho@cri.ensmp.fr>
Reviewed-by: "Iwata, Aya" <iwata.aya@jp.fujitsu.com>
Reviewed-by: Daniel Verite <daniel@manitou-mail.org>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/alpine.DEB.2.21.1904132231510.8961@lancre
At present, if we want to update publications in a subscription, we
can use SET PUBLICATION. However, it requires supplying all
publications that exists and the new publications. If we want to add
new publications, it's inconvenient. The new syntax only supplies the
new publications. When the refresh is true, it only refreshes the new
publications.
Author: Japin Li <japinli@hotmail.com>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/MEYP282MB166939D0D6C480B7FBE7EFFBB6BC0@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
To allow inserts in parallel-mode this feature has to ensure that all the
constraints, triggers, etc. are parallel-safe for the partition hierarchy
which is costly and we need to find a better way to do that. Additionally,
we could have used existing cached information in some cases like indexes,
domains, etc. to determine the parallel-safety.
List of commits reverted, in reverse chronological order:
ed62d3737c Doc: Update description for parallel insert reloption.
c8f78b6161 Add a new GUC and a reloption to enable inserts in parallel-mode.
c5be48f092 Improve FK trigger parallel-safety check added by 05c8482f7f.
e2cda3c20a Fix use of relcache TriggerDesc field introduced by commit 05c8482f7f.
e4e87a32cc Fix valgrind issue in commit 05c8482f7f.
05c8482f7f Enable parallel SELECT for "INSERT INTO ... SELECT ...".
Discussion: https://postgr.es/m/E1lMiB9-0001c3-SY@gemulon.postgresql.org
There is now a per-column COMPRESSION option which can be set to pglz
(the default, and the only option in up until now) or lz4. Or, if you
like, you can set the new default_toast_compression GUC to lz4, and
then that will be the default for new table columns for which no value
is specified. We don't have lz4 support in the PostgreSQL code, so
to use lz4 compression, PostgreSQL must be built --with-lz4.
In general, TOAST compression means compression of individual column
values, not the whole tuple, and those values can either be compressed
inline within the tuple or compressed and then stored externally in
the TOAST table, so those properties also apply to this feature.
Prior to this commit, a TOAST pointer has two unused bits as part of
the va_extsize field, and a compessed datum has two unused bits as
part of the va_rawsize field. These bits are unused because the length
of a varlena is limited to 1GB; we now use them to indicate the
compression type that was used. This means we only have bit space for
2 more built-in compresison types, but we could work around that
problem, if necessary, by introducing a new vartag_external value for
any further types we end up wanting to add. Hopefully, it won't be
too important to offer a wide selection of algorithms here, since
each one we add not only takes more coding but also adds a build
dependency for every packager. Nevertheless, it seems worth doing
at least this much, because LZ4 gets better compression than PGLZ
with less CPU usage.
It's possible for LZ4-compressed datums to leak into composite type
values stored on disk, just as it is for PGLZ. It's also possible for
LZ4-compressed attributes to be copied into a different table via SQL
commands such as CREATE TABLE AS or INSERT .. SELECT. It would be
expensive to force such values to be decompressed, so PostgreSQL has
never done so. For the same reasons, we also don't force recompression
of already-compressed values even if the target table prefers a
different compression method than was used for the source data. These
architectural decisions are perhaps arguable but revisiting them is
well beyond the scope of what seemed possible to do as part of this
project. However, it's relatively cheap to recompress as part of
VACUUM FULL or CLUSTER, so this commit adjusts those commands to do
so, if the configured compression method of the table happens not to
match what was used for some column value stored therein.
Dilip Kumar. The original patches on which this work was based were
written by Ildus Kurbangaliev, and those were patches were based on
even earlier work by Nikita Glukhov, but the design has since changed
very substantially, since allow a potentially large number of
compression methods that could be added and dropped on a running
system proved too problematic given some of the architectural issues
mentioned above; the choice of which specific compression method to
add first is now different; and a lot of the code has been heavily
refactored. More recently, Justin Przyby helped quite a bit with
testing and reviewing and this version also includes some code
contributions from him. Other design input and review from Tomas
Vondra, Álvaro Herrera, Andres Freund, Oleg Bartunov, Alexander
Korotkov, and me.
Discussion: http://postgr.es/m/20170907194236.4cefce96%40wp.localdomain
Discussion: http://postgr.es/m/CAFiTN-uUpX3ck%3DK0mLEk-G_kUQY%3DSNOTeqdaNRR9FMdQrHKebw%40mail.gmail.com
Only "IMPORT" was showing as result of the completion, while IMPORT
FOREIGN SCHEMA is the only command using this keyword in first
position. This changes the completion to show the full command name
instead of just "IMPORT".
Reviewed-by: Georgios Kokolatos, Julien Rouhaud
Discussion: https://postgr.es/m/YFL6JneBiuMWYyoh@paquier.xyz