Commit Graph

571 Commits

Author SHA1 Message Date
Fujii Masao 3b733fcd04 Display the time when the process started waiting for the lock, in pg_locks.
This commit adds new column "waitstart" into pg_locks view. This column
reports the time when the server process started waiting for the lock
if the lock is not held. This information is useful, for example, when
examining the amount of time to wait on a lock by subtracting
"waitstart" in pg_locks from the current time, and identify the lock
that the processes are waiting for very long.

This feature uses the current time obtained for the deadlock timeout
timer as "waitstart" (i.e., the time when this process started waiting
for the lock). Since getting the current time newly can cause overhead,
we reuse the already-obtained time to avoid that overhead.

Note that "waitstart" is updated without holding the lock table's
partition lock, to avoid the overhead by additional lock acquisition.
This can cause "waitstart" in pg_locks to become NULL for a very short
period of time after the wait started even though "granted" is false.
This is OK in practice because we can assume that users are likely to
look at "waitstart" when waiting for the lock for a long time.

Bump catalog version.

Author: Atsushi Torikoshi
Reviewed-by: Ian Lawrence Barwick, Robert Haas, Justin Pryzby, Fujii Masao
Discussion: https://postgr.es/m/a96013dc51cdc56b2a2b84fa8a16a993@oss.nttdata.com
2021-02-09 18:10:19 +09:00
Tom Lane 479331406e Doc: consistently identify OID catalog columns that can be zero.
Not all OID-reference columns that can contain zeroes (indicating
"no reference") were explicitly marked in catalogs.sgml.  Fix that,
and try to make the style a little more consistent while at it ---
for example, consistently write "zero" not "0" for these cases.

Joel Jacobson and Tom Lane

Discussion: https://postgr.es/m/4ed9a372-7bf9-479a-926c-ae8e774717a8@www.fastmail.com
2021-02-02 16:15:29 -05:00
Tom Lane 951862eda5 Doc: improve documentation of pg_proc.protrftypes.
Add a "references" link pointing to pg_type, as we have for other arrays
of type OIDs.  Wordsmith the explanation a bit.

Joel Jacobson, additional editing by me

Discussion: https://postgr.es/m/d1cc628c-3953-4209-957b-29427acc38c8@www.fastmail.com
2021-01-25 11:20:17 -05:00
Alvaro Herrera ebfe2dbd6b
Prevent drop of tablespaces used by partitioned relations
When a tablespace is used in a partitioned relation (per commits
ca4103025d in pg12 for tables and 33e6c34c32 in pg11 for indexes),
it is possible to drop the tablespace, potentially causing various
problems.  One such was reported in bug #16577, where a rewriting ALTER
TABLE causes a server crash.

Protect against this by using pg_shdepend to keep track of tablespaces
when used for relations that don't keep physical files; we now abort a
tablespace if we see that the tablespace is referenced from any
partitioned relations.

Backpatch this to 11, where this problem has been latent all along.  We
don't try to create pg_shdepend entries for existing partitioned
indexes/tables, but any ones that are modified going forward will be
protected.

Note slight behavior change: when trying to drop a tablespace that
contains both regular tables as well as partitioned ones, you'd
previously get ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE and now you'll
get ERRCODE_DEPENDENT_OBJECTS_STILL_EXIST.  Arguably, the latter is more
correct.

It is possible to add protecting pg_shdepend entries for existing
tables/indexes, by doing
  ALTER TABLE ONLY some_partitioned_table SET TABLESPACE pg_default;
  ALTER TABLE ONLY some_partitioned_table SET TABLESPACE original_tablespace;
for each partitioned table/index that is not in the database default
tablespace.  Because these partitioned objects do not have storage, no
file needs to be actually moved, so it shouldn't take more time than
what's required to acquire locks.

This query can be used to search for such relations:
SELECT ... FROM pg_class WHERE relkind IN ('p', 'I') AND reltablespace <> 0

Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/16577-881633a9f9894fd5@postgresql.org
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
2021-01-14 15:32:14 -03:00
Michael Paquier 90fbf7c57d Fix typos and grammar in docs and comments
This fixes several areas of the documentation and some comments in
matters of style, grammar, or even format.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20201222041153.GK30237@telsasoft.com
2020-12-24 17:05:49 +09:00
Alexander Korotkov 6df7a9698b Multirange datatypes
Multiranges are basically sorted arrays of non-overlapping ranges with
set-theoretic operations defined over them.

Since v14, each range type automatically gets a corresponding multirange
datatype.  There are both manual and automatic mechanisms for naming multirange
types.  Once can specify multirange type name using multirange_type_name
attribute in CREATE TYPE.  Otherwise, a multirange type name is generated
automatically.  If the range type name contains "range" then we change that to
"multirange".  Otherwise, we add "_multirange" to the end.

Implementation of multiranges comes with a space-efficient internal
representation format, which evades extra paddings and duplicated storage of
oids.  Altogether this format allows fetching a particular range by its index
in O(n).

Statistic gathering and selectivity estimation are implemented for multiranges.
For this purpose, stored multirange is approximated as union range without gaps.
This field will likely need improvements in the future.

Catversion is bumped.

Discussion: https://postgr.es/m/CALNJ-vSUpQ_Y%3DjXvTxt1VYFztaBSsWVXeF1y6gTYQ4bOiWDLgQ%40mail.gmail.com
Discussion: https://postgr.es/m/a0b8026459d1e6167933be2104a6174e7d40d0ab.camel%40j-davis.com#fe7218c83b08068bfffb0c5293eceda0
Author: Paul Jungwirth, revised by me
Reviewed-by: David Fetter, Corey Huinker, Jeff Davis, Pavel Stehule
Reviewed-by: Alvaro Herrera, Tom Lane, Isaac Morland, David G. Johnston
Reviewed-by: Zhihong Yu, Alexander Korotkov
2020-12-20 07:20:33 +03:00
Michael Paquier bce641a2af doc: Fix explanation related to pg_shmem_allocations
Offsets are shown as NULL only for anonymous allocations.

Author: Benoit Lobréau
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CAPE8EZ5Lnoyqoz7aZpvQM0E8sW+hw+k6G2NULe+m4arFRrA1aA@mail.gmail.com
Backpatch-through: 13
2020-12-16 10:36:03 +09:00
Tom Lane c7aba7c14e Support subscripting of arbitrary types, not only arrays.
This patch generalizes the subscripting infrastructure so that any
data type can be subscripted, if it provides a handler function to
define what that means.  Traditional variable-length (varlena) arrays
all use array_subscript_handler(), while the existing fixed-length
types that support subscripting use raw_array_subscript_handler().
It's expected that other types that want to use subscripting notation
will define their own handlers.  (This patch provides no such new
features, though; it only lays the foundation for them.)

To do this, move the parser's semantic processing of subscripts
(including coercion to whatever data type is required) into a
method callback supplied by the handler.  On the execution side,
replace the ExecEvalSubscriptingRef* layer of functions with direct
calls to callback-supplied execution routines.  (Thus, essentially
no new run-time overhead should be caused by this patch.  Indeed,
there is room to remove some overhead by supplying specialized
execution routines.  This patch does a little bit in that line,
but more could be done.)

Additional work is required here and there to remove formerly
hard-wired assumptions about the result type, collation, etc
of a SubscriptingRef expression node; and to remove assumptions
that the subscript values must be integers.

One useful side-effect of this is that we now have a less squishy
mechanism for identifying whether a data type is a "true" array:
instead of wiring in weird rules about typlen, we can look to see
if pg_type.typsubscript == F_ARRAY_SUBSCRIPT_HANDLER.  For this
to be bulletproof, we have to forbid user-defined types from using
that handler directly; but there seems no good reason for them to
do so.

This patch also removes assumptions that the number of subscripts
is limited to MAXDIM (6), or indeed has any hard-wired limit.
That limit still applies to types handled by array_subscript_handler
or raw_array_subscript_handler, but to discourage other dependencies
on this constant, I've moved it from c.h to utils/array.h.

Dmitry Dolgov, reviewed at various times by Tom Lane, Arthur Zakirov,
Peter Eisentraut, Pavel Stehule

Discussion: https://postgr.es/m/CA+q6zcVDuGBv=M0FqBYX8DPebS3F_0KQ6OVFobGJPM507_SZ_w@mail.gmail.com
Discussion: https://postgr.es/m/CA+q6zcVovR+XY4mfk-7oNk-rF91gH0PebnNfuUjuuDsyHjOcVA@mail.gmail.com
2020-12-09 12:40:37 -05:00
Heikki Linnakangas 415dc20096 docs: ulink all references to RFC's
Make sure that the first mentions of RFC's are ulinked to their ietf.org
entry, and subsequent ones are marked as acronyms. This makes references
to RFC's consistent across the documentation.

Author: Daniel Gustafsson
Discussion: https://www.postgresql.org/message-id/2C697878-4D01-4F06-8312-2FEDE931E973%40yesql.se
2020-12-01 14:36:30 +02:00
Fujii Masao ef60de67eb doc: Add note about pg_settings and customized options into catalogs.sgml.
The pg_settings view does not display customized options until
the extension module that defines them has been loaded. This commit
add the note about that behavior, into the docs.

Author: John Naylor
Reviewed-by: Tom Lane, Fujii Masao
Discussion: https://postgr.es/m/CAFBsxsGsBZsG=cLM0Op5HFb2Ks6SzJrOc_eRO_jcKSNuqFRKnQ@mail.gmail.com
2020-11-09 15:10:26 +09:00
Thomas Munro 257836a755 Track collation versions for indexes.
Record the current version of dependent collations in pg_depend when
creating or rebuilding an index.  When accessing the index later, warn
that the index may be corrupted if the current version doesn't match.

Thanks to Douglas Doole, Peter Eisentraut, Christoph Berg, Laurenz Albe,
Michael Paquier, Robert Haas, Tom Lane and others for very helpful
discussion.

Author: Thomas Munro <thomas.munro@gmail.com>
Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com> (earlier versions)
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 01:19:50 +13:00
Thomas Munro cd6f479e79 Add pg_depend.refobjversion.
Provide a place for the version of referenced database objects to be
recorded.  A follow-up commit will use this to record dependencies on
collation versions for indexes, but similar ideas for other kinds of
objects have also been mooted.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 00:44:59 +13:00
Thomas Munro 7d1297df08 Remove pg_collation.collversion.
This model couldn't be extended to cover the default collation, and
didn't have any information about the affected database objects when the
version changed.  Remove, in preparation for a follow-up commit that
will add a new mechanism.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Discussion: https://postgr.es/m/CAEepm%3D0uEQCpfq_%2BLYFBdArCe4Ot98t1aR4eYiYTe%3DyavQygiQ%40mail.gmail.com
2020-11-03 00:44:59 +13:00
Tom Lane b401fa206d Doc: clarify description for pg_constraint.convalidated.
Jimmy Angelakos

Discussion: https://postgr.es/m/CABgVKCW_zPnvFXn24FTF0299_yU6+1p6JRUc0xpiZFWEXH1_jg@mail.gmail.com
2020-10-30 10:38:49 -04:00
Heikki Linnakangas c5f42daa60 Misc documentation fixes.
- Misc grammar and punctuation fixes.

- Stylistic cleanup: use spaces between function arguments and JSON fields
  in examples. For example "foo(a,b)" -> "foo(a, b)". Add semicolon after
  last END in a few PL/pgSQL examples that were missing them.

- Make sentence that talked about "..." and ".." operators more clear,
  by avoiding to end the sentence with "..". That makes it look the same
  as "..."

- Fix syntax description for HAVING: HAVING conditions cannot be repeated

Patch by Justin Pryzby, per Yaroslav Schekin's report. Backpatch to all
supported versions, to the extent that the patch applies easily.

Discussion: https://www.postgresql.org/message-id/20201005191922.GE17626%40telsasoft.com
2020-10-19 19:28:54 +03:00
Peter Eisentraut 2453ea1422 Support for OUT parameters in procedures
Unlike for functions, OUT parameters for procedures are part of the
signature.  Therefore, they have to be listed in pg_proc.proargtypes
as well as mentioned in ALTER PROCEDURE and DROP PROCEDURE.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/2b8490fe-51af-e671-c504-47359dc453c5@2ndquadrant.com
2020-10-05 09:21:43 +02:00
Peter Eisentraut 9081bddbd7 Improve <xref> vs. <command> formatting in the documentation
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
2020-10-03 16:40:02 +02:00
Tom Lane 9436041ed8 Copy editing: fix a bunch of misspellings and poor wording.
99% of this is docs, but also a couple of comments.  No code changes.

Justin Pryzby

Discussion: https://postgr.es/m/20200919175804.GE30557@telsasoft.com
2020-09-21 12:43:42 -04:00
Tom Lane 1ed6b89563 Remove support for postfix (right-unary) operators.
This feature has been a thorn in our sides for a long time, causing
many grammatical ambiguity problems.  It doesn't seem worth the
pain to continue to support it, so remove it.

There are some follow-on improvements we can make in the grammar,
but this commit only removes the bare minimum number of productions,
plus assorted backend support code.

Note that pg_dump and psql continue to have full support, since
they may be used against older servers.  However, pg_dump warns
about postfix operators.  There is also a check in pg_upgrade.

Documentation-wise, I (tgl) largely removed the "left unary"
terminology in favor of saying "prefix operator", which is
a more standard and IMO less confusing term.

I included a catversion bump, although no initial catalog data
changes here, to mark the boundary at which oprkind = 'r'
stopped being valid in pg_operator.

Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor

Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
2020-09-17 19:38:05 -04:00
Peter Eisentraut 5ccf322118 doc: Make SQL command names in the catalog documentation links
In passing, fix the initdb references to be <application> rather than
<command>, which is what we normally use.

Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/87mu5xqc11.fsf@wibble.ilmari.org
2020-09-03 13:17:22 +02:00
Peter Eisentraut cb6eb4a09e doc: Add missing cross-links in system catalog documentation
This makes the first mention of a system catalog or view in each
paragraph in the system system catalog and view documentation pages
hyperlinks, for easier navigation.

Also linkify the first mention of pg_hba.conf in pg_hba_file_rules, as
that's more specific and easier to spot than the link to the client
authentication chapter.

Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/87mu5xqc11.fsf@wibble.ilmari.org
2020-09-03 13:17:22 +02:00
Tom Lane 3d351d916b Redefine pg_class.reltuples to be -1 before the first VACUUM or ANALYZE.
Historically, we've considered the state with relpages and reltuples
both zero as indicating that we do not know the table's tuple density.
This is problematic because it's impossible to distinguish "never yet
vacuumed" from "vacuumed and seen to be empty".  In particular, a user
cannot use VACUUM or ANALYZE to override the planner's normal heuristic
that an empty table should not be believed to be empty because it is
probably about to get populated.  That heuristic is a good safety
measure, so I don't care to abandon it, but there should be a way to
override it if the table is indeed intended to stay empty.

Hence, represent the initial state of ignorance by setting reltuples
to -1 (relpages is still set to zero), and apply the minimum-ten-pages
heuristic only when reltuples is still -1.  If the table is empty,
VACUUM or ANALYZE (but not CREATE INDEX) will override that to
reltuples = relpages = 0, and then we'll plan on that basis.

This requires a bunch of fiddly little changes, but we can get rid of
some ugly kluges that were formerly needed to maintain the old definition.

One notable point is that FDWs' GetForeignRelSize methods will see
baserel->tuples = -1 when no ANALYZE has been done on the foreign table.
That seems like a net improvement, since those methods were formerly
also in the dark about what baserel->tuples = 0 really meant.  Still,
it is an API change.

I bumped catversion because code predating this change would get confused
by seeing reltuples = -1.

Discussion: https://postgr.es/m/F02298E0-6EF4-49A1-BCB6-C484794D9ACC@thebuild.com
2020-08-30 12:21:51 -04:00
Fujii Masao 29dd6d8bc6 Prevent non-superusers from reading pg_backend_memory_contexts, by default.
pg_backend_memory_contexts view contains some internal information of
memory contexts. Since exposing them to any users by default may cause
security issue, this commit allows only superusers to read this view,
by default, like we do for pg_shmem_allocations view.

Bump catalog version.

Author: Atsushi Torikoshi
Reviewed-by: Michael Paquier, Fujii Masao
Discussion: https://postgr.es/m/1414992.1597849297@sss.pgh.pa.us
2020-08-26 10:50:02 +09:00
Fujii Masao 3e98c0bafb Add pg_backend_memory_contexts system view.
This view displays the usages of all the memory contexts of the server
process attached to the current session. This information is useful to
investigate the cause of backend-local memory bloat.

This information can be also collected by calling
MemoryContextStats(TopMemoryContext) via a debugger. But this technique
cannot be uesd in some environments because no debugger is available there.
And it outputs lots of text messages and it's not easy to analyze them.
So, pg_backend_memory_contexts view allows us to access to backend-local
memory contexts information more easily.

Bump catalog version.

Author: Atsushi Torikoshi, Fujii Masao
Reviewed-by: Tatsuhito Kasahara, Andres Freund, Daniel Gustafsson, Robert Haas, Michael Paquier
Discussion: https://postgr.es/m/72a656e0f71d0860161e0b3f67e4d771@oss.nttdata.com
2020-08-19 15:34:43 +09:00
Noah Misch 566372b3d6 Prevent concurrent SimpleLruTruncate() for any given SLRU.
The SimpleLruTruncate() header comment states the new coding rule.  To
achieve this, add locktype "frozenid" and two LWLocks.  This closes a
rare opportunity for data loss, which manifested as "apparent
wraparound" or "could not access status of transaction" errors.  Data
loss is more likely in pg_multixact, due to released branches' thin
margin between multiStopLimit and multiWrapLimit.  If a user's physical
replication primary logged ":  apparent wraparound" messages, the user
should rebuild standbys of that primary regardless of symptoms.  At less
risk is a cluster having emitted "not accepting commands" errors or
"must be vacuumed" warnings at some point.  One can test a cluster for
this data loss by running VACUUM FREEZE in every database.  Back-patch
to 9.5 (all supported versions).

Discussion: https://postgr.es/m/20190218073103.GA1434723@rfd.leadboat.com
2020-08-15 10:15:53 -07:00
Michael Paquier 903134fcc0 doc: Mention index references in pg_inherits
Partitioned indexes are also registered in pg_inherits, but the
description of this catalog did not reflect that.

Author: Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/87k0ynj35y.fsf@wibble.ilmari.org
Backpatch-through: 11
2020-07-30 15:48:44 +09:00
Tom Lane 0fa0b487b5 Correctly mark pg_subscription_rel.srsublsn as nullable.
The code has always set this column to NULL when it's not valid,
but the catalog header's description failed to reflect that,
as did the SGML docs, as did some of the code.  To prevent future
coding errors of the same ilk, let's hide the field from C code
as though it were variable-length (which, in a sense, it is).

As with commit 72eab84a5, we can only fix this cleanly in HEAD
and v13; the problem extends further back but we'll need some
klugery in the released branches.

Discussion: https://postgr.es/m/367660.1595202498@sss.pgh.pa.us
2020-07-20 14:55:56 -04:00
Fujii Masao c3fe108c02 Rename wal_keep_segments to wal_keep_size.
max_slot_wal_keep_size that was added in v13 and wal_keep_segments are
the GUC parameters to specify how much WAL files to retain for
the standby servers. While max_slot_wal_keep_size accepts the number of
bytes of WAL files, wal_keep_segments accepts the number of WAL files.
This difference of setting units between those similar parameters could
be confusing to users.

To alleviate this situation, this commit renames wal_keep_segments to
wal_keep_size, and make users specify the WAL size in it instead of
the number of WAL files.

There was also the idea to rename max_slot_wal_keep_size to
max_slot_wal_keep_segments, in the discussion. But we have been moving
away from measuring in segments, for example, checkpoint_segments was
replaced by max_wal_size. So we concluded to rename wal_keep_segments
to wal_keep_size.

Back-patch to v13 where max_slot_wal_keep_size was added.

Author: Fujii Masao
Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, David Steele
Discussion: https://postgr.es/m/574b4ea3-e0f9-b175-ead2-ebea7faea855@oss.nttdata.com
2020-07-20 13:30:18 +09:00
Fujii Masao d05b172a76 Add generic_plans and custom_plans fields into pg_prepared_statements.
There was no easy way to find how many times generic and custom plans
have been executed for a prepared statement. This commit exposes those
numbers of times in pg_prepared_statements view.

Author: Atsushi Torikoshi, Kyotaro Horiguchi
Reviewed-by: Tatsuro Yamada, Masahiro Ikeda, Fujii Masao
Discussion: https://postgr.es/m/CACZ0uYHZ4M=NZpofH6JuPHeX=__5xcDELF8hT8_2T+R55w4RQw@mail.gmail.com
2020-07-20 11:55:50 +09:00
Tom Lane 72eab84a56 Correctly mark pg_subscription.subslotname as nullable.
Due to the layout of this catalog, subslotname has to be explicitly
marked BKI_FORCE_NULL, else initdb will default to the assumption
that it's non-nullable.  Since, in fact, CREATE/ALTER SUBSCRIPTION
will store null values there, the existing marking is just wrong,
and has been since this catalog was invented.

We haven't noticed because not much in the system actually depends
on attnotnull being truthful.  However, JIT'ed tuple deconstruction
does depend on that in some cases, allowing crashes or wrong answers
in queries that inspect pg_subscription.  Commit 9de77b545 quite
accidentally exposed this on the buildfarm members that force JIT
activation.

Back-patch to v13.  The problem goes further back, but we cannot
force initdb in released branches, so some klugier solution will
be needed there.  Before working on that, push this simple fix
to try to get the buildfarm back to green.

Discussion: https://postgr.es/m/4118109.1595096139@sss.pgh.pa.us
2020-07-19 12:37:23 -04:00
Tom Lane 9de77b5453 Allow logical replication to transfer data in binary format.
This patch adds a "binary" option to CREATE/ALTER SUBSCRIPTION.
When that's set, the publisher will send data using the data type's
typsend function if any, rather than typoutput.  This is generally
faster, if slightly less robust.

As committed, we won't try to transfer user-defined array or composite
types in binary, for fear that type OIDs won't match at the subscriber.
This might be changed later, but it seems like fit material for a
follow-on patch.

Dave Cramer, reviewed by Daniel Gustafsson, Petr Jelinek, and others;
adjusted some by me

Discussion: https://postgr.es/m/CADK3HH+R3xMn=8t3Ct+uD+qJ1KD=Hbif5NFMJ+d5DkoCzp6Vgw@mail.gmail.com
2020-07-18 12:44:51 -04:00
Tom Lane f3faf35f37 Don't create pg_type entries for sequences or toast tables.
Commit f7f70d5e2 left one inconsistency behind: we're still creating
pg_type entries for the composite types of sequences and toast tables,
but not arrays over those composites.  But there seems precious little
reason to have named composite types for toast tables, and not much more
to have them for sequences (especially given the thought that sequences
may someday not be standalone relations at all).

So, let's close that inconsistency by removing these composite types,
rather than adding arrays for them.  This buys back a little bit of
the initial pg_type bloat added by the previous patch, and could be
a significant savings in a large database with many toast tables.

Aside from a small logic rearrangement in heap_create_with_catalog,
this patch mostly needs to clean up some places that were assuming that
pg_class.reltype always has a valid value.  Those are really pre-existing
bugs, given that it's documented otherwise; notably, the plpgsql changes
fix code that gives "cache lookup failed for type 0" on indexes today.
But none of these seem interesting enough to back-patch.

Also, remove the pg_dump/pg_upgrade infrastructure for propagating
a toast table's pg_type OID into the new database, since we no longer
need that.

Discussion: https://postgr.es/m/761F1389-C6A8-4C15-80CE-950C961F5341@gmail.com
2020-07-07 15:43:22 -04:00
Alvaro Herrera a8aaa0c786
Morph pg_replication_slots.min_safe_lsn to safe_wal_size
The previous definition of the column was almost universally disliked,
so provide this updated definition which is more useful for monitoring
purposes: a large positive value is good, while zero or a negative value
means danger.  This should be operationally more convenient.

Backpatch to 13, where the new column to pg_replication_slots (and the
feature it represents) were added.

Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Discussion: https://postgr.es/m/9ddfbf8c-2f67-904d-44ed-cf8bc5916228@oss.nttdata.com
2020-07-07 13:08:00 -04:00
Fujii Masao 8f9b6d4057 doc: Correct description of restart_lsn in pg_replication_slots
Previously the document explained that restart_lsn indicates the LSN of
oldest WAL won't be automatically removed during checkpoints. But
since v13 this was no longer true thanks to max_slot_wal_keep_size.

Back-patch to v13 where max_slot_wal_keep_size was added.

Author: Fujii Masao
Discussion: https://postgr.es/m/6497f1e9-3148-c5da-7e49-b2fddad9a42f@oss.nttdata.com
2020-07-03 12:08:35 +09:00
Alvaro Herrera b8fd4e02c6
Adjust max_slot_wal_keep_size behavior per review
In pg_replication_slot, change output from normal/reserved/lost to
reserved/extended/unreserved/ lost, which better expresses the possible
states particularly near the time where segments are no longer safe but
checkpoint has not run yet.

Under the new definition, reserved means the slot is consuming WAL
that's still under the normal WAL size constraints; extended means it's
consuming WAL that's being protected by wal_keep_segments or the slot
itself, whose size is below max_slot_wal_keep_size; unreserved means the
WAL is no longer safe, but checkpoint has not yet removed those files.
Such as slot is in imminent danger, but can still continue for a little
while and may catch up to the reserved WAL space.

Also, there were some bugs in the calculations used to report the
status; fixed those.

Backpatch to 13.

Reported-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20200616.120236.1809496990963386593.horikyota.ntt@gmail.com
2020-06-24 14:23:39 -04:00
Michael Paquier fe186b4c20 Fix inconsistent markups in catalogs.sgml
Some fields related to pg_opclass and pg_opfamily were using incorrect
markups, listing them as structname instead of structfield.

Author: Fabien Coelho
Discussion: https://postgr.es/m/alpine.DEB.2.22.394.2006210903560.859381@pseudo
2020-06-22 13:40:04 +09:00
Fujii Masao 92f9468657 doc: Update the layout of "Viewing Statistics" section.
This commit updates the "Viewing Statistics" section more like
the existing catalogs chapter.

- Change its layout so that an introductory paragrap is put above
   the table for each statistics view. Previously the explanations
   were below the tables.

- Separate each view to different section and add index terms for them.

Author: Fujii Masao
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/6f8a482c-b3fa-4ed9-21c3-6d222a2cb87d@oss.nttdata.com
2020-05-29 17:14:33 +09:00
Michael Paquier 5832396432 Doc: Fix order of pg_shmem_allocations in system view list
pg_shmem_allocations was in the wrong position with pg_stats.

Author: Ian Barwick
Discussion: https://postgr.es/m/de7279d4-7ea0-037f-d7d2-1161682339db@2ndquadrant.com
2020-05-25 15:18:11 +09:00
Michael Paquier 39cb2ee09c Doc: Fix description of pg_class.relreplident
The description missed a comma and lacked an explanation of what happens
with REPLICA IDENTITY USING INDEX when the dependent index is dropped.

Author: Marina Polyakova
Reviewed-by: Daniel Gustafsson, Michael Paquier
Discussion: https://postgr.es/m/ad1a0badc32658b1bbb07aa312346a1d@postgrespro.ru
Backpatch-through: 9.5
2020-05-20 14:20:50 +09:00
Tom Lane 474e7da648 Change locktype "speculative token" to "spectoken".
It's just weird that this name wasn't chosen to look like an
identifier.  The suspicion that it wasn't thought about too
hard is reinforced by the fact that it wasn't documented in
the pg_locks view (until I did so, a day or two back).

Update, and add a comment reminding future adjusters of this
array to fix the docs too.

Do some desultory wordsmithing on various entries in the wait
events tables.

Discussion: https://postgr.es/m/24595.1589326879@sss.pgh.pa.us
2020-05-15 21:47:34 -04:00
Tom Lane 4fa8bd392d Doc: split up wait_event table.
The previous design for this table didn't really work in narrow views,
such as PDF output; besides which its reliance on large morerows
values made it a pain to maintain (cf ab3e4fbd5, for example).

I experimented with a couple of ways to fix it, but the best and
simplest is to split it up into a separate table for each event
type category.

I also rearranged the event ordering to be strictly alphabetical,
as nobody would ever be able to find entries otherwise.

There is work afoot to revise the set of event names described
in this table, but this commit just changes the layout, not the
contents.

In passing, add a missing entry to pg_locks.locktype,
and cross-reference that to the related wait event list.

Discussion: https://postgr.es/m/6916.1589146280@sss.pgh.pa.us
2020-05-13 23:36:58 -04:00
Tom Lane a042750646 Doc: reformat catalog/view description tables.
This changes our catalog and view descriptions to use a style inspired
by the new format for function/operator tables: each table entry is
formatted roughly like a <varlistentry>, with the column name and type
on the first line and then an indented description.  This provides much
more room for expansive descriptions than we had before, and thereby
eliminates a passel of PDF build warnings.

Discussion: https://postgr.es/m/12984.1588643549@sss.pgh.pa.us
2020-05-13 23:03:39 -04:00
Tom Lane 9356e43544 Doc: fix assorted misstatements of fact in catalog & system view docs.
I made up a very crude hack to compare the docs with reality (as
embodied in the system catalogs) ... and indeed they don't match
everywhere.  Missing oid columns, wrong data types, wrong "references"
links, columns listed in the wrong order.  None of this seems quite
important enough to back-patch.
2020-05-09 19:09:44 -04:00
Michael Paquier dd0f37ecce Fix collection of typos and grammar mistakes in the tree
This fixes some comments and documentation new as of Postgres 13.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20200408165653.GF2228@telsasoft.com
2020-04-10 11:18:39 +09:00
Peter Eisentraut 83fd4532a7 Allow publishing partition changes via ancestors
To control whether partition changes are replicated using their own
identity and schema or an ancestor's, add a new parameter that can be
set per publication named 'publish_via_partition_root'.

This allows replicating a partitioned table into a different partition
structure on the subscriber.

Author: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Rafia Sabih <rafia.pghackers@gmail.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Reviewed-by: Petr Jelinek <petr@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+HiwqH=Y85vRK3mOdjEkqFK+E=ST=eQiHdpj43L=_eJMOOznQ@mail.gmail.com
2020-04-08 11:19:23 +02:00
Alvaro Herrera c655077639
Allow users to limit storage reserved by replication slots
Replication slots are useful to retain data that may be needed by a
replication system.  But experience has shown that allowing them to
retain excessive data can lead to the primary failing because of running
out of space.  This new feature allows the user to configure a maximum
amount of space to be reserved using the new option
max_slot_wal_keep_size.  Slots that overrun that space are invalidated
at checkpoint time, enabling the storage to be released.

Author: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20170228.122736.123383594.horiguchi.kyotaro@lab.ntt.co.jp
2020-04-07 18:35:00 -04:00
Tomas Vondra c31132d87c Document pg_statistic_ext.stxstattarget
Commit d06215d03b added a new attribute to pg_statistic_ext catalog, but
failed to add it to document it properly.

Reported-by: Noriyoshi Shinoda <noriyoshi.shinoda@hpe.com>
2020-03-18 16:48:12 +01:00
Tom Lane fe30e7ebfa Allow ALTER TYPE to change some properties of a base type.
Specifically, this patch allows ALTER TYPE to:
* Change the default TOAST strategy for a toastable base type;
* Promote a non-toastable type to toastable;
* Add/remove binary I/O functions for a type;
* Add/remove typmod I/O functions for a type;
* Add/remove a custom ANALYZE statistics functions for a type.

The first of these can be done by the type's owner; all the others
require superuser privilege since misuse could cause problems.

The main motivation for this patch is to allow extensions to
upgrade the feature sets of their data types, so the set of
alterable properties is biased towards that use-case.  However
it's also true that changing some other properties would be
a lot harder, as they get baked into physical storage and/or
stored expressions that depend on the type.

Along the way, refactor GenerateTypeDependencies() to make it easier
to call, refactor DefineType's volatility checks so they can be shared
by AlterType, and teach typcache.c that it might have to reload data
from the type's pg_type row, a scenario it never handled before.
Also rearrange alter_type.sgml a bit for clarity (put the
composite-type operations together).

Tomas Vondra and Tom Lane

Discussion: https://postgr.es/m/20200228004440.b23ein4qvmxnlpht@development
2020-03-06 12:19:29 -05:00
Alvaro Herrera b9b408c487
Record parents of triggers
This let us get rid of a recently introduced ugly hack (commit
1fa846f1c9).

Author: Álvaro Herrera
Reviewed-by: Amit Langote, Tom Lane
Discussion: https://postgr.es/m/20200217215641.GA29784@alvherre.pgsql
2020-02-27 13:23:33 -03:00
Tom Lane 50fc694e43 Invent "trusted" extensions, and remove the pg_pltemplate catalog.
This patch creates a new extension property, "trusted".  An extension
that's marked that way in its control file can be installed by a
non-superuser who has the CREATE privilege on the current database,
even if the extension contains objects that normally would have to be
created by a superuser.  The objects within the extension will (by
default) be owned by the bootstrap superuser, but the extension itself
will be owned by the calling user.  This allows replicating the old
behavior around trusted procedural languages, without all the
special-case logic in CREATE LANGUAGE.  We have, however, chosen to
loosen the rules slightly: formerly, only a database owner could take
advantage of the special case that allowed installation of a trusted
language, but now anyone who has CREATE privilege can do so.

Having done that, we can delete the pg_pltemplate catalog, moving the
knowledge it contained into the extension script files for the various
PLs.  This ends up being no change at all for the in-core PLs, but it is
a large step forward for external PLs: they can now have the same ease
of installation as core PLs do.  The old "trusted PL" behavior was only
available to PLs that had entries in pg_pltemplate, but now any
extension can be marked trusted if appropriate.

This also removes one of the stumbling blocks for our Python 2 -> 3
migration, since the association of "plpythonu" with Python 2 is no
longer hard-wired into pg_pltemplate's initial contents.  Exactly where
we go from here on that front remains to be settled, but one problem
is fixed.

Patch by me, reviewed by Peter Eisentraut, Stephen Frost, and others.

Discussion: https://postgr.es/m/5889.1566415762@sss.pgh.pa.us
2020-01-29 18:42:43 -05:00
Robert Haas ed10f32e37 Add pg_shmem_allocations view.
This tells you about allocations that have been made from the main
shared memory segment. The original patch also tried to show information
about dynamic shared memory allocation as well, but I decided to
leave that problem for another time.

Andres Freund and Robert Haas, reviewed by Michael Paquier, Marti
Raudsepp, Tom Lane, Álvaro Herrera, and Kyotaro Horiguchi.

Discussion: http://postgr.es/m/20140504114417.GM12715@awork2.anarazel.de
2020-01-09 10:59:07 -05:00
Peter Eisentraut cbe63d02d0 doc: Use proper em and en dashes 2019-10-25 20:39:41 +02:00
Tom Lane 732457b5d2 Doc: improve docs about pg_statistic_ext_data.
Commit aa087ec64 was a bit over-hasty about the doc changes needed
while splitting pg_statistic_ext_data off from pg_statistic_ext.
It duplicated one para and inserted another in what seems to me
to be the wrong section.  Fix that up, and in passing do some minor
copy-editing.

Per report from noborusai.

Discussion: https://postgr.es/m/CAAM3qnLXLUz4mOBkqa8jxigpKhKNxzSuvwpjvCRPvO5EqWjxSg@mail.gmail.com
2019-10-06 14:14:45 -04:00
Michael Paquier 0431a78746 Doc: Improve wording of multiple places in documentation
This has been found during its translation.

Author: Liudmila Mantrova
Discussion: https://postgr.es/m/CAEkD-mDJHV3bhgezu3MUafJLoAKsOOT86+wHukKU8_NeiJYhLQ@mail.gmail.com
Backpatch-through: 12
2019-08-20 12:36:31 +09:00
Bruce Momjian 909a7b6b8e docs: remove pg_roles mention of the oid column being displayed
It is now always displayed in PG 12+.

Discussion: https://postgr.es/m/b6ec6167-5dd5-6347-ac1d-1fd49382019f@2ndquadrant.com

Author: Ian Barwick

Backpatch-through: 12
2019-07-10 14:24:36 -04:00
Michael Paquier 6b8548964b Fix inconsistencies in the code
This addresses a couple of issues in the code:
- Typos and inconsistencies in comments and function declarations.
- Removal of unreferenced function declarations.
- Removal of unnecessary compile flags.
- A cleanup error in regressplans.sh.

Author: Alexander Lakhin
Discussion: https://postgr.es/m/0c991fdf-2670-1997-c027-772a420c4604@gmail.com
2019-07-08 13:15:09 +09:00
Tom Lane 145b18688c Doc: remove obsolete description of oid column as being "hidden".
Looks like one copy of this text didn't get updated.

Justin Pryzby

Discussion: https://postgr.es/m/20190701155932.GA22866@telsasoft.com
2019-07-01 12:09:06 -04:00
Michael Paquier 252f9a2580 Fix description of pg_class.relam for table access methods
Author: Ian Barwick
Discussion: https://postgr.es/m/087a6961-1aaf-e36c-b712-bd5a644da20a@2ndquadrant.com
2019-06-20 13:04:56 +09:00
Tomas Vondra aa087ec64f Add pg_stats_ext view for extended statistics
Regular per-column statistics are stored in pg_statistics catalog, which
is however rather difficult to read, so we also have pg_stats view with
a human-reablable version of the data.

For extended statistic the catalog was fairly easy to read, so we did
not have such human-readable view so far.  Commit 9b6babfa2d however did
split the catalog into two, which makes querying harder.  Furthermore,
we want to show the multi-column MCV list in a way similar to per-column
stats (and not as a bytea value).

This commit introduces pg_stats_ext view, joining the two catalogs and
massaging the data to produce human-readable output similar to pg_stats.
It also considers RLS and access privileges - the data is shown only when
the user has access to all columns the extended statistic is defined on.

Bumped CATVERSION due to adding new system view.

Author: Dean Rasheed, with improvements by me
Reviewed-by: Dean Rasheed, John Naylor
Discussion: https://postgr.es/m/CAEZATCUhT9rt7Ui%3DVdx4N%3D%3DVV5XOK5dsXfnGgVOz_JhAicB%3DZA%40mail.gmail.com
2019-06-16 01:20:39 +02:00
Tomas Vondra 6cbfb784c3 Rework the pg_statistic_ext catalog
Since extended statistic got introduced in PostgreSQL 10, there was a
single catalog pg_statistic_ext storing both the definitions and built
statistic.  That's however problematic when a user is supposed to have
access only to the definitions, but not to user data.

Consider for example pg_dump on a database with RLS enabled - if the
pg_statistic_ext catalog respects RLS (which it should, if it contains
user data), pg_dump would not see any records and the result would not
define any extended statistics.  That would be a surprising behavior.

Until now this was not a pressing issue, because the existing types of
extended statistic (functional dependencies and ndistinct coefficients)
do not include any user data directly.  This changed with introduction
of MCV lists, which do include most common combinations of values.

The easiest way to fix this is to split the pg_statistic_ext catalog
into two - one for definitions, one for the built statistic values.
The new catalog is called pg_statistic_ext_data, and we're maintaining
a 1:1 relationship with the old catalog - either there are matching
records in both catalogs, or neither of them.

Bumped CATVERSION due to changing system catalog definitions.

Author: Dean Rasheed, with improvements by me
Reviewed-by: Dean Rasheed, John Naylor
Discussion: https://postgr.es/m/CAEZATCUhT9rt7Ui%3DVdx4N%3D%3DVV5XOK5dsXfnGgVOz_JhAicB%3DZA%40mail.gmail.com
2019-06-16 01:20:31 +02:00
Michael Paquier 56b78626c7 Fix some documentation about access methods
Author: Guillaume Lelarge
Discussion: https://postgr.es/m/CAECtzeWPz4JikzUqZdMjqPTe8dAP3nZxPD-58Y-Hhvirg0fF+A@mail.gmail.com
2019-05-29 11:37:37 -04:00
Andres Freund f6b39171f3 docs: cleanup/remove/update references to OID column.
I (Andres) missed these in 578b229718.

Author: Justin Pryzby, editorialized a bit by Andres Freund
Reviewed-By: Daniel Verite, Andres Freund
Discussion: https://postgr.es/m/20190408002847.GA904@telsasoft.com
2019-04-17 17:22:56 -07:00
Andres Freund 86cc06d1cf table: docs: fix typos and grammar.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20190404055138.GA24864@telsasoft.com
2019-04-05 09:47:10 -07:00
Andres Freund b73c3a1196 tableam: basic documentation.
This adds documentation about the user oriented parts of table access
methods (i.e. the default_table_access_method GUC and the USING clause
for CREATE TABLE etc), adds a basic chapter about the table access
method interface, and adds a note to storage.sgml that it's contents
don't necessarily apply for non-builtin AMs.

Author: Haribabu Kommi and Andres Freund
Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
2019-04-03 17:40:29 -07:00
Peter Eisentraut fc22b6623b Generated columns
This is an SQL-standard feature that allows creating columns that are
computed from expressions rather than assigned, similar to a view or
materialized view but on a column basis.

This implements one kind of generated column: stored (computed on
write).  Another kind, virtual (computed on read), is planned for the
future, and some room is left for it.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b151f851-4019-bdb1-699e-ebab07d2f40a@2ndquadrant.com
2019-03-30 08:15:57 +01:00
Tomas Vondra 7300a69950 Add support for multivariate MCV lists
Introduce a third extended statistic type, supported by the CREATE
STATISTICS command - MCV lists, a generalization of the statistic
already built and used for individual columns.

Compared to the already supported types (n-distinct coefficients and
functional dependencies), MCV lists are more complex, include column
values and allow estimation of much wider range of common clauses
(equality and inequality conditions, IS NULL, IS NOT NULL etc.).
Similarly to the other types, a new pseudo-type (pg_mcv_list) is used.

Author: Tomas Vondra
Reviewed-by: Dean Rasheed, David Rowley, Mark Dilger, Alvaro Herrera
Discussion: https://postgr.es/m/dfdac334-9cf2-2597-fb27-f0fb3753f435@2ndquadrant.com
2019-03-27 18:32:18 +01:00
Peter Eisentraut 5e1963fb76 Collations with nondeterministic comparison
This adds a flag "deterministic" to collations.  If that is false,
such a collation disables various optimizations that assume that
strings are equal only if they are byte-wise equal.  That then allows
use cases such as case-insensitive or accent-insensitive comparisons
or handling of strings with different Unicode normal forms.

This functionality is only supported with the ICU provider.  At least
glibc doesn't appear to have any locales that work in a
nondeterministic way, so it's not worth supporting this for the libc
provider.

The term "deterministic comparison" in this context is from Unicode
Technical Standard #10
(https://unicode.org/reports/tr10/#Deterministic_Comparison).

This patch makes changes in three areas:

- CREATE COLLATION DDL changes and system catalog changes to support
  this new flag.

- Many executor nodes and auxiliary code are extended to track
  collations.  Previously, this code would just throw away collation
  information, because the eventually-called user-defined functions
  didn't use it since they only cared about equality, which didn't
  need collation information.

- String data type functions that do equality comparisons and hashing
  are changed to take the (non-)deterministic flag into account.  For
  comparison, this just means skipping various shortcuts and tie
  breakers that use byte-wise comparison.  For hashing, we first need
  to convert the input string to a canonical "sort key" using the ICU
  analogue of strxfrm().

Reviewed-by: Daniel Verite <daniel@manitou-mail.org>
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Discussion: https://www.postgresql.org/message-id/flat/1ccc668f-4cbc-0bef-af67-450b47cdfee7@2ndquadrant.com
2019-03-22 12:12:43 +01:00
Tom Lane 1d92a0c9f7 Redesign the partition dependency mechanism.
The original setup for dependencies of partitioned objects had
serious problems:

1. It did not verify that a drop cascading to a partition-child object
also cascaded to at least one of the object's partition parents.  Now,
normally a child object would share all its dependencies with one or
another parent (e.g. a child index's opclass dependencies would be shared
with the parent index), so that this oversight is usually harmless.
But if some dependency failed to fit this pattern, the child could be
dropped while all its parents remain, creating a logically broken
situation.  (It's easy to construct artificial cases that break it,
such as attaching an unrelated extension dependency to the child object
and then dropping the extension.  I'm not sure if any less-artificial
cases exist.)

2. Management of partition dependencies during ATTACH/DETACH PARTITION
was complicated and buggy; for example, after detaching a partition
table it was possible to create cases where a formerly-child index
should be dropped and was not, because the correct set of dependencies
had not been reconstructed.

Less seriously, because multiple partition relationships were
represented identically in pg_depend, there was an order-of-traversal
dependency on which partition parent was cited in error messages.
We also had some pre-existing order-of-traversal hazards for error
messages related to internal and extension dependencies.  This is
cosmetic to users but causes testing problems.

To fix #1, add a check at the end of the partition tree traversal
to ensure that at least one partition parent got deleted.  To fix #2,
establish a new policy that partition dependencies are in addition to,
not instead of, a child object's usual dependencies; in this way
ATTACH/DETACH PARTITION need not cope with adding or removing the
usual dependencies.

To fix the cosmetic problem, distinguish between primary and secondary
partition dependency entries in pg_depend, by giving them different
deptypes.  (They behave identically except for having different
priorities for being cited in error messages.)  This means that the
former 'I' dependency type is replaced with new 'P' and 'S' types.

This also fixes a longstanding bug that after handling an internal
dependency by recursing to the owning object, findDependentObjects
did not verify that the current target was now scheduled for deletion,
and did not apply the current recursion level's objflags to it.
Perhaps that should be back-patched; but in the back branches it
would only matter if some concurrent transaction had removed the
internal-linkage pg_depend entry before the recursive call found it,
or the recursive call somehow failed to find it, both of which seem
unlikely.

Catversion bump because the contents of pg_depend change for
partitioning relationships.

Patch HEAD only.  It's annoying that we're not fixing #2 in v11,
but there seems no practical way to do so given that the problem
is exactly a poor choice of what entries to put in pg_depend.
We can't really fix that while staying compatible with what's
in pg_depend in existing v11 installations.

Discussion: https://postgr.es/m/CAH2-Wzkypv1R+teZrr71U23J578NnTBt2X8+Y=Odr4pOdW1rXg@mail.gmail.com
2019-02-11 14:41:17 -05:00
Tom Lane 1fb57af920 Create the infrastructure for planner support functions.
Rename/repurpose pg_proc.protransform as "prosupport".  The idea is
still that it names an internal function that provides knowledge to
the planner about the behavior of the function it's attached to;
but redesign the API specification so that it's not limited to doing
just one thing, but can support an extensible set of requests.

The original purpose of simplifying a function call is handled by
the first request type to be invented, SupportRequestSimplify.
Adjust all the existing transform functions to handle this API,
and rename them fron "xxx_transform" to "xxx_support" to reflect
the potential generalization of what they do.  (Since we never
previously provided any way for extensions to add transform functions,
this change doesn't create an API break for them.)

Also add DDL and pg_dump support for attaching a support function to a
user-defined function.  Unfortunately, DDL access has to be restricted
to superusers, at least for now; but seeing that support functions
will pretty much have to be written in C, that limitation is just
theoretical.  (This support is untested in this patch, but a follow-on
patch will add cases that exercise it.)

Discussion: https://postgr.es/m/15193.1548028093@sss.pgh.pa.us
2019-02-09 18:08:48 -05:00
Tom Lane 586b98fdf1 Make type "name" collation-aware.
The "name" comparison operators now all support collations, making them
functionally equivalent to "text" comparisons, except for the different
physical representation of the datatype.  They do, in fact, mostly share
the varstr_cmp and varstr_sortsupport infrastructure, which has been
slightly enlarged to handle the case.

To avoid changes in the default behavior of the datatype, set name's
typcollation to C_COLLATION_OID not DEFAULT_COLLATION_OID, so that
by default comparisons to a name value will continue to use strcmp
semantics.  (This would have been the case for system catalog columns
anyway, because of commit 6b0faf723, but doing this makes it true for
user-created name columns as well.  In particular, this avoids
locale-dependent changes in our regression test results.)

In consequence, tweak a couple of places that made assumptions about
collatable base types always having typcollation DEFAULT_COLLATION_OID.
I have not, however, attempted to relax the restriction that user-
defined collatable types must have that.  Hence, "name" doesn't
behave quite like a user-defined type; it acts more like a domain
with COLLATE "C".  (Conceivably, if we ever get rid of the need for
catalog name columns to be fixed-length, "name" could actually become
such a domain over text.  But that'd be a pretty massive undertaking,
and I'm not volunteering.)

Discussion: https://postgr.es/m/15938.1544377821@sss.pgh.pa.us
2018-12-19 17:46:25 -05:00
Tom Lane 5e09280057 Make pg_statistic and related code account more honestly for collations.
When we first put in collations support, we basically punted on teaching
pg_statistic, ANALYZE, and the planner selectivity functions about that.
They've just used DEFAULT_COLLATION_OID independently of the actual
collation of the data.  It's time to improve that, so:

* Add columns to pg_statistic that record the specific collation associated
with each statistics slot.

* Teach ANALYZE to use the column's actual collation when comparing values
for statistical purposes, and record this in the appropriate slot.  (Note
that type-specific typanalyze functions are now expected to fill
stats->stacoll with the appropriate collation, too.)

* Teach assorted selectivity functions to use the actual collation of
the stats they are looking at, instead of just assuming it's
DEFAULT_COLLATION_OID.

This should give noticeably better results in selectivity estimates for
columns with nondefault collations, at least for query clauses that use
that same collation (which would be the default behavior in most cases).
It's still true that comparisons with explicit COLLATE clauses different
from the stored data's collation won't be well-estimated, but that's no
worse than before.  Also, this patch does make the first step towards
doing better with that, which is that it's now theoretically possible to
collect stats for a collation other than the column's own collation.

Patch by me; thanks to Peter Eisentraut for review.

Discussion: https://postgr.es/m/14706.1544630227@sss.pgh.pa.us
2018-12-14 12:52:49 -05:00
Tom Lane afc4a78a30 Refactor documentation about privileges to centralize the info.
Expand section 5.6 "Privileges" to include the full definition of
each privilege type, and an explanation of aclitem privilege displays,
along with some helpful summary tables.  Most of this material came
out of the GRANT reference page, although some of it is new.
Adjust a bunch of links that were pointing to GRANT to point to 5.6.

Fabien Coelho and Tom Lane, reviewed by Bradley DeJong

Discussion: https://postgr.es/m/alpine.DEB.2.21.1807311735200.20743@lancre
2018-12-03 11:40:49 -05:00
Andres Freund 578b229718 Remove WITH OIDS support, change oid catalog column visibility.
Previously tables declared WITH OIDS, including a significant fraction
of the catalog tables, stored the oid column not as a normal column,
but as part of the tuple header.

This special column was not shown by default, which was somewhat odd,
as it's often (consider e.g. pg_class.oid) one of the more important
parts of a row.  Neither pg_dump nor COPY included the contents of the
oid column by default.

The fact that the oid column was not an ordinary column necessitated a
significant amount of special case code to support oid columns. That
already was painful for the existing, but upcoming work aiming to make
table storage pluggable, would have required expanding and duplicating
that "specialness" significantly.

WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0).
Remove it.

Removing includes:
- CREATE TABLE and ALTER TABLE syntax for declaring the table to be
  WITH OIDS has been removed (WITH (oids[ = true]) will error out)
- pg_dump does not support dumping tables declared WITH OIDS and will
  issue a warning when dumping one (and ignore the oid column).
- restoring an pg_dump archive with pg_restore will warn when
  restoring a table with oid contents (and ignore the oid column)
- COPY will refuse to load binary dump that includes oids.
- pg_upgrade will error out when encountering tables declared WITH
  OIDS, they have to be altered to remove the oid column first.
- Functionality to access the oid of the last inserted row (like
  plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed.

The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false)
for CREATE TABLE) is still supported. While that requires a bit of
support code, it seems unnecessary to break applications / dumps that
do not use oids, and are explicit about not using them.

The biggest user of WITH OID columns was postgres' catalog. This
commit changes all 'magic' oid columns to be columns that are normally
declared and stored. To reduce unnecessary query breakage all the
newly added columns are still named 'oid', even if a table's column
naming scheme would indicate 'reloid' or such.  This obviously
requires adapting a lot code, mostly replacing oid access via
HeapTupleGetOid() with access to the underlying Form_pg_*->oid column.

The bootstrap process now assigns oids for all oid columns in
genbki.pl that do not have an explicit value (starting at the largest
oid previously used), only oids assigned later by oids will be above
FirstBootstrapObjectId. As the oid column now is a normal column the
special bootstrap syntax for oids has been removed.

Oids are not automatically assigned during insertion anymore, all
backend code explicitly assigns oids with GetNewOidWithIndex(). For
the rare case that insertions into the catalog via SQL are called for
the new pg_nextoid() function can be used (which only works on catalog
tables).

The fact that oid columns on system tables are now normal columns
means that they will be included in the set of columns expanded
by * (i.e. SELECT * FROM pg_class will now include the table's oid,
previously it did not). It'd not technically be hard to hide oid
column by default, but that'd mean confusing behavior would either
have to be carried forward forever, or it'd cause breakage down the
line.

While it's not unlikely that further adjustments are needed, the
scope/invasiveness of the patch makes it worthwhile to get merge this
now. It's painful to maintain externally, too complicated to commit
after the code code freeze, and a dependency of a number of other
patches.

Catversion bump, for obvious reasons.

Author: Andres Freund, with contributions by John Naylor
Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
2018-11-20 16:00:17 -08:00
Peter Eisentraut 96b00c433c Remove obsolete pg_constraint.consrc column
This has been deprecated and effectively unused for a long time.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
2018-11-01 20:36:05 +01:00
Peter Eisentraut fe5038236c Remove obsolete pg_attrdef.adsrc column
This has been deprecated and effectively unused for a long time.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
2018-11-01 20:35:42 +01:00
Michael Paquier 0993b8ada5 Improve description of pg_attrdef in documentation
The reference to pg_attribute is switched to a link, which is more
useful for the html documentation.  The conditions under which a default
value is defined for a given column are made more general.

Author: Daniel Gustafsson
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/0E8748E3-8B7D-445E-9ABA-09DA5C7345CC@yesql.se
2018-10-29 16:38:54 +09:00
Michael Paquier 55853d666c Clarify descriptions of relhassubclass and relispartition in pg_class
Three places are fixed, one for each author.

Reported-by: Tom Lane
Author: Tom Lane, Amit Langote, Michael Paquier
Discussion: https://postgr.es/m/82470.1540177167@sss.pgh.pa.us
2018-10-22 15:26:28 +09:00
Andres Freund cda6a8d01d Remove deprecated abstime, reltime, tinterval datatypes.
These types have been deprecated for a *long* time.

Catversion bump, for obvious reasons.

Author: Andres Freund
Discussion:
    https://postgr.es/m/20181009192237.34wjp3nmw7oynmmr@alap3.anarazel.de
    https://postgr.es/m/20171213080506.cwjkpcz3bkk6yz2u@alap3.anarazel.de
    https://postgr.es/m/25615.1513115237@sss.pgh.pa.us
2018-10-11 11:59:15 -07:00
Alvaro Herrera c076f3d74a Remove pg_constraint.conincluding
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
2018-09-03 12:59:26 -03:00
Peter Eisentraut b19495772e doc: Update uses of the word "procedure"
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>
2018-08-22 14:44:49 +02:00
Alvaro Herrera f6f8d55c4b Add 'n' to list of possible values to pg_default_acl.defaclobjtype
This was missed in commit ab89e465cb20; backpatch to v10.

Author: Fabien Coelho <coelho@cri.ensmp.fr>
Discussion: https://postgr.es/m/alpine.DEB.2.21.1807302243001.13230@lancre
2018-08-03 16:45:08 -04:00
Tom Lane 701fd0bbc9 Drop the rule against included index columns duplicating key columns.
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
2018-07-18 14:43:03 -04:00
Michael Paquier 56a7147213 Block replication slot advance for these not yet reserving WAL
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
2018-07-11 08:56:24 +09:00
Alvaro Herrera 550091f218 Add relkind 'I' to catalog.sgml's list relkinds
Commit 8b08f7d482 added a relkind for local partitioned indexes, but
failed to add it to pg_class's list of possible relkinds.  Repair.

Author: Peter Geoghegan, Michaël Paquier
Discussion: https://postgr.es/m/CAH2-WzkOKptQiE51Bh4_xeEHhaBwHkZkGtKizrFMgEkfUuRRQg@mail.gmail.com
2018-05-09 13:46:12 -03:00
Robert Haas f955d7ee16 Documentation updates for partitioning.
Takayuki Tsunakawa

Discussion: http://postgr.es/m/0A3221C70F24FB45833433255569204D1F965627@G01JPEXMBYT05
2018-05-07 09:48:47 -04:00
Tom Lane 4094031dd3 Assorted minor doc/comment fixes.
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
2018-04-28 11:46:15 -04:00
Teodor Sigaev 03c11796a9 Improve covering index documentation
Add missed description of pg_constraint.conincluding

Shinoda, Noriyoshi and Alexander Korotkov
2018-04-09 17:53:42 +03:00
Teodor Sigaev 8224de4f42 Indexes with INCLUDE columns and their support in B-tree
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
2018-04-07 23:00:39 +03:00
Peter Eisentraut 039eb6e92f Logical replication support for TRUNCATE
Update the built-in logical replication system to make use of the
previously added logical decoding for TRUNCATE support.  Add the
required truncate callback to pgoutput and a new logical replication
protocol message.

Publications get a new attribute to determine whether to replicate
truncate actions.  When updating a publication via pg_dump from an older
version, this is not set, thus preserving the previous behavior.

Author: Simon Riggs <simon@2ndquadrant.com>
Author: Marco Nenciarini <marco.nenciarini@2ndquadrant.it>
Author: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Reviewed-by: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
2018-04-07 11:34:11 -04:00
Andrew Dunstan 16828d5c02 Fast ALTER TABLE ADD COLUMN with a non-NULL default
Currently adding a column to a table with a non-NULL default results in
a rewrite of the table. For large tables this can be both expensive and
disruptive. This patch removes the need for the rewrite as long as the
default value is not volatile. The default expression is evaluated at
the time of the ALTER TABLE and the result stored in a new column
(attmissingval) in pg_attribute, and a new column (atthasmissing) is set
to true. Any existing row when fetched will be supplied with the
attmissingval. New rows will have the supplied value or the default and
so will never need the attmissingval.

Any time the table is rewritten all the atthasmissing and attmissingval
settings for the attributes are cleared, as they are no longer needed.

The most visible code change from this is in heap_attisnull, which
acquires a third TupleDesc argument, allowing it to detect a missing
value if there is one. In many cases where it is known that there will
not be any (e.g.  catalog relations) NULL can be passed for this
argument.

Andrew Dunstan, heavily modified from an original patch from Serge
Rielau.
Reviewed by Tom Lane, Andres Freund, Tomas Vondra and David Rowley.

Discussion: https://postgr.es/m/31e2e921-7002-4c27-59f5-51f08404c858@2ndQuadrant.com
2018-03-28 10:43:52 +10:30
Alvaro Herrera 86f575948c Allow FOR EACH ROW triggers on partitioned tables
Previously, FOR EACH ROW triggers were not allowed in partitioned
tables.  Now we allow AFTER triggers on them, and on trigger creation we
cascade to create an identical trigger in each partition.  We also clone
the triggers to each partition that is created or attached later.

This means that deferred unique keys are allowed on partitioned tables,
too.

Author: Álvaro Herrera
Reviewed-by: Peter Eisentraut, Simon Riggs, Amit Langote, Robert Haas,
	Thomas Munro
Discussion: https://postgr.es/m/20171229225319.ajltgss2ojkfd3kp@alvherre.pgsql
2018-03-23 10:48:22 -03:00
Tom Lane 7c91a0364f Sync up our various ways of estimating pg_class.reltuples.
VACUUM thought that reltuples represents the total number of tuples in
the relation, while ANALYZE counted only live tuples.  This can cause
"flapping" in the value when background vacuums and analyzes happen
separately.  The planner's use of reltuples essentially assumes that
it's the count of live (visible) tuples, so let's standardize on having
it mean live tuples.

Another issue is that the definition of "live tuple" isn't totally clear;
what should be done with INSERT_IN_PROGRESS or DELETE_IN_PROGRESS tuples?
ANALYZE's choices in this regard are made on the assumption that if the
originating transaction commits at all, it will happen after ANALYZE
finishes, so we should ignore the effects of the in-progress transaction
--- unless it is our own transaction, and then we should count it.
Let's propagate this definition into VACUUM, too.

Likewise propagate this definition into CREATE INDEX, and into
contrib/pgstattuple's pgstattuple_approx() function.

Tomas Vondra, reviewed by Haribabu Kommi, some corrections by me

Discussion: https://postgr.es/m/16db4468-edfa-830a-f921-39a50498e77e@2ndquadrant.com
2018-03-22 15:47:41 -04:00
Peter Eisentraut 325f2ec555 Handle heap rewrites even better in logical decoding
Logical decoding should not publish anything about tables created as
part of a heap rewrite during DDL.  Those tables don't exist externally,
so consumers of logical decoding cannot do anything sensible with that
information.  In ab28feae2b, we worked
around this for built-in logical replication, but that was hack.

This is a more proper fix: We mark such transient heaps using the new
field pg_class.relwrite, linking to the original relation OID.  By
default, we ignore them in logical decoding before they get to the
output plugin.  Optionally, a plugin can register their interest in
getting such changes, if they handle DDL specially, in which case the
new field will help them get information about the actual table.

Reviewed-by: Craig Ringer <craig@2ndquadrant.com>
2018-03-21 09:15:04 -04:00
Peter Eisentraut f66e8bf875 Remove pg_class.relhaspkey
It is not used for anything internally, and it cannot be relied on for
external uses, so it can just be removed.  To correct recommended way to
check for a primary key is in pg_index.

Discussion: https://www.postgresql.org/message-id/flat/b1a24c6c-6913-f89c-674e-0704f0ed69db@2ndquadrant.com
2018-03-14 15:31:34 -04:00
Peter Eisentraut fd1a421fe6 Add prokind column, replacing proisagg and proiswindow
The new column distinguishes normal functions, procedures, aggregates,
and window functions.  This replaces the existing columns proisagg and
proiswindow, and replaces the convention that procedures are indicated
by prorettype == 0.  Also change prorettype to be VOIDOID for procedures.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-02 13:48:33 -05:00
Alvaro Herrera 8b08f7d482 Local partitioned indexes
When CREATE INDEX is run on a partitioned table, create catalog entries
for an index on the partitioned table (which is just a placeholder since
the table proper has no data of its own), and recurse to create actual
indexes on the existing partitions; create them in future partitions
also.

As a convenience gadget, if the new index definition matches some
existing index in partitions, these are picked up and used instead of
creating new ones.  Whichever way these indexes come about, they become
attached to the index on the parent table and are dropped alongside it,
and cannot be dropped on isolation unless they are detached first.

To support pg_dump'ing these indexes, add commands
    CREATE INDEX ON ONLY <table>
(which creates the index on the parent partitioned table, without
recursing) and
    ALTER INDEX ATTACH PARTITION
(which is used after the indexes have been created individually on each
partition, to attach them to the parent index).  These reconstruct prior
database state exactly.

Reviewed-by: (in alphabetical order) Peter Eisentraut, Robert Haas, Amit
	Langote, Jesper Pedersen, Simon Riggs, David Rowley
Discussion: https://postgr.es/m/20171113170646.gzweigyrgg6pwsg4@alvherre.pgsql
2018-01-19 11:49:22 -03:00
Peter Eisentraut e4128ee767 SQL procedures
This adds a new object type "procedure" that is similar to a function
but does not have a return type and is invoked by the new CALL statement
instead of SELECT or similar.  This implementation is aligned with the
SQL standard and compatible with or similar to other SQL implementations.

This commit adds new commands CALL, CREATE/ALTER/DROP PROCEDURE, as well
as ALTER/DROP ROUTINE that can refer to either a function or a
procedure (or an aggregate function, as an extension to SQL).  There is
also support for procedures in various utility commands such as COMMENT
and GRANT, as well as support in pg_dump and psql.  Support for defining
procedures is available in all the languages supplied by the core
distribution.

While this commit is mainly syntax sugar around existing functionality,
future features will rely on having procedures as a separate object
type.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2017-11-30 11:03:20 -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
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
Tom Lane 4de2d4fba3 Explicitly track whether aggregate final functions modify transition state.
Up to now, there's been hard-wired assumptions that normal aggregates'
final functions never modify their transition states, while ordered-set
aggregates' final functions always do.  This has always been a bit
limiting, and in particular it's getting in the way of improving the
built-in ordered-set aggregates to allow merging of transition states.
Therefore, let's introduce catalog and CREATE AGGREGATE infrastructure
that lets the finalfn's behavior be declared explicitly.

There are now three possibilities for the finalfn behavior: it's purely
read-only, it trashes the transition state irrecoverably, or it changes
the state in such a way that no more transfn calls are possible but the
state can still be passed to other, compatible finalfns.  There are no
examples of this third case today, but we'll shortly make the built-in
OSAs act like that.

This change allows user-defined aggregates to explicitly disclaim support
for use as window functions, and/or to prevent transition state merging,
if their implementations cannot handle that.  While it was previously
possible to handle the window case with a run-time error check, there was
not any way to prevent transition state merging, which in retrospect is
something commit 804163bc2 should have provided for.  But better late
than never.

In passing, split out pg_aggregate.c's extern function declarations into
a new header file pg_aggregate_fn.h, similarly to what we've done for
some other catalog headers, so that pg_aggregate.h itself can be safe
for frontend files to include.  This lets pg_dump use the symbolic
names for relevant constants.

Discussion: https://postgr.es/m/4834.1507849699@sss.pgh.pa.us
2017-10-14 15:21:39 -04:00