Commit Graph

14191 Commits

Author SHA1 Message Date
Alexander Korotkov 16d489b0fe Numeric error suppression in jsonpath
Add support of numeric error suppression to jsonpath as it's required by
standard.  This commit doesn't use PG_TRY()/PG_CATCH() in order to implement
that.  Instead, it provides internal versions of numeric functions used, which
support error suppression.

Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Author: Alexander Korotkov, Nikita Glukhov
Reviewed-by: Tomas Vondra
2019-03-16 12:21:19 +03:00
Alexander Korotkov 72b6460336 Partial implementation of SQL/JSON path language
SQL 2016 standards among other things contains set of SQL/JSON features for
JSON processing inside of relational database.  The core of SQL/JSON is JSON
path language, allowing access parts of JSON documents and make computations
over them.  This commit implements partial support JSON path language as
separate datatype called "jsonpath".  The implementation is partial because
it's lacking datetime support and suppression of numeric errors.  Missing
features will be added later by separate commits.

Support of SQL/JSON features requires implementation of separate nodes, and it
will be considered in subsequent patches.  This commit includes following
set of plain functions, allowing to execute jsonpath over jsonb values:

 * jsonb_path_exists(jsonb, jsonpath[, jsonb, bool]),
 * jsonb_path_match(jsonb, jsonpath[, jsonb, bool]),
 * jsonb_path_query(jsonb, jsonpath[, jsonb, bool]),
 * jsonb_path_query_array(jsonb, jsonpath[, jsonb, bool]).
 * jsonb_path_query_first(jsonb, jsonpath[, jsonb, bool]).

This commit also implements "jsonb @? jsonpath" and "jsonb @@ jsonpath", which
are wrappers over jsonpath_exists(jsonb, jsonpath) and jsonpath_predicate(jsonb,
jsonpath) correspondingly.  These operators will have an index support
(implemented in subsequent patches).

Catversion bumped, to add new functions and operators.

Code was written by Nikita Glukhov and Teodor Sigaev, revised by me.
Documentation was written by Oleg Bartunov and Liudmila Mantrova.  The work
was inspired by Oleg Bartunov.

Discussion: https://postgr.es/m/fcc6fc6a-b497-f39a-923d-aa34d0c588e8%402ndQuadrant.com
Author: Nikita Glukhov, Teodor Sigaev, Alexander Korotkov, Oleg Bartunov, Liudmila Mantrova
Reviewed-by: Tomas Vondra, Andrew Dunstan, Pavel Stehule, Alexander Korotkov
2019-03-16 12:16:48 +03:00
Thomas Munro bb16aba50c Enable parallel query with SERIALIZABLE isolation.
Previously, the SERIALIZABLE isolation level prevented parallel query
from being used.  Allow the two features to be used together by
sharing the leader's SERIALIZABLEXACT with parallel workers.

An extra per-SERIALIZABLEXACT LWLock is introduced to make it safe to
share, and new logic is introduced to coordinate the early release
of the SERIALIZABLEXACT required for the SXACT_FLAG_RO_SAFE
optimization, as follows:

The first backend to observe the SXACT_FLAG_RO_SAFE flag (set by
some other transaction) will 'partially release' the SERIALIZABLEXACT,
meaning that the conflicts and locks it holds are released, but the
SERIALIZABLEXACT itself will remain active because other backends
might still have a pointer to it.

Whenever any backend notices the SXACT_FLAG_RO_SAFE flag, it clears
its own MySerializableXact variable and frees local resources so that
it can skip SSI checks for the rest of the transaction.  In the
special case of the leader process, it transfers the SERIALIZABLEXACT
to a new variable SavedSerializableXact, so that it can be completely
released at the end of the transaction after all workers have exited.

Remove the serializable_okay flag added to CreateParallelContext() by
commit 9da0cc35, because it's now redundant.

Author: Thomas Munro
Reviewed-by: Haribabu Kommi, Robert Haas, Masahiko Sawada, Kevin Grittner
Discussion: https://postgr.es/m/CAEepm=0gXGYhtrVDWOTHS8SQQy_=S9xo+8oCxGLWZAOoeJ=yzQ@mail.gmail.com
2019-03-15 17:47:04 +13:00
Amit Kapila 13e8643bfc During pg_upgrade, conditionally skip transfer of FSMs.
If a heap on the old cluster has 4 pages or fewer, and the old cluster
was PG v11 or earlier, don't copy or link the FSM. This will shrink
space usage for installations with large numbers of small tables.

This will allow pg_upgrade to take advantage of commit b0eaa4c51b where
we have avoided creation of the free space map for small heap relations.

Author: John Naylor
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CACPNZCu4cOdm3uGnNEGXivy7Gz8UWyQjynDpdkPGabQ18_zK6g%40mail.gmail.com
2019-03-15 08:25:57 +05:30
Tom Lane 401b87a24f Sync commentary in transam.h and bki.sgml.
Commit a6417078c missed updating some comments in transam.h about
reservation of high OIDs for development purposes.  Also tamp down
an over-optimistic comment there about how easy it'd be to change
FirstNormalObjectId.

Earlier, commit 09568ec3d failed to update bki.sgml for the split
between genbki.pl-assigned OIDs and those assigned during initdb.

Also fix genbki.pl so that it will complain if it overruns
that split.  It's possible that doing so would have no very bad
consequences, but that's no excuse for not detecting it.
2019-03-14 00:23:40 -04:00
Thomas Munro c6c9474aaf Use condition variables to wait for checkpoints.
Previously we used a polling/sleeping loop to wait for checkpoints
to begin and end, which leads to up to a couple hundred milliseconds
of needless thumb-twiddling.  Use condition variables instead.

Author: Thomas Munro
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/CA%2BhUKGLY7sDe%2Bbg1K%3DbnEzOofGoo4bJHYh9%2BcDCXJepb6DQmLw%40mail.gmail.com
2019-03-14 10:59:33 +13:00
Robert Haas bbb96c3704 Allow ALTER TABLE .. SET NOT NULL to skip provably unnecessary scans.
If existing CHECK or NOT NULL constraints preclude the presence
of nulls, we need not look to see whether any are present.

Sergei Kornilov, reviewed by Stephen Frost, Ildar Musin, David Rowley,
and by me.

Discussion: http://postgr.es/m/81911511895540@web58j.yandex.ru
2019-03-13 08:55:00 -04:00
Magnus Hagander 95fa9f1a13 Remove extra comma
Author: Christoph Berg <myon@debian.org>
2019-03-13 13:41:14 +01:00
Michael Paquier 6dd263cfaa Rename pg_verify_checksums to pg_checksums
The current tool name is too restrictive and focuses only on verifying
checksums.  As more options to control checksums for an offline cluster
are planned to be added, switch to a more generic name.  Documentation
as well as all past references to the tool are updated.

Author: Michael Paquier
Reviewed-by: Michael Banck, Fabien Coelho, Seigei Kornilov
Discussion: https://postgr.es/m/20181221201616.GD4974@nighthawk.caipicrew.dd-dns.de
2019-03-13 10:43:20 +09:00
Tom Lane f1d85aa98e Add support for hyperbolic functions, as well as log10().
The SQL:2016 standard adds support for the hyperbolic functions
sinh(), cosh(), and tanh().  POSIX has long required libm to
provide those functions as well as their inverses asinh(),
acosh(), atanh().  Hence, let's just expose the libm functions
to the SQL level.  As with the trig functions, we only implement
versions for float8, not numeric.

For the moment, we'll assume that all platforms actually do have
these functions; if experience teaches otherwise, some autoconf
effort may be needed.

SQL:2016 also adds support for base-10 logarithm, but with the
function name log10(), whereas the name we've long used is log().
Add aliases named log10() for the float8 and numeric versions.

Lætitia Avrot

Discussion: https://postgr.es/m/CAB_COdguG22LO=rnxDQ2DW1uzv8aQoUzyDQNJjrR4k00XSgm5w@mail.gmail.com
2019-03-12 15:55:09 -04:00
Tom Lane 3aa0395d4e Remove remaining hard-wired OID references in the initial catalog data.
In the v11-era commits that taught genbki.pl to resolve symbolic
OID references in the initial catalog data, we didn't bother to
make every last reference symbolic; some of the catalogs have so
few initial rows that it didn't seem worthwhile.

However, the new project policy that OIDs assigned by new patches
should be automatically renumberable changes this calculus.
A patch that wants to add a row in one of these catalogs would have
a problem when the OID it assigns gets renumbered.  Hence, do the
mop-up work needed to make all OID references in initial data be
symbolic, and establish an associated project policy that we'll
never again write a hard-wired OID reference there.

No catversion bump since the contents of postgres.bki aren't
actually changed by this commit.

Discussion: https://postgr.es/m/CAH2-WzmMTGMcPuph4OvsO7Ykut0AOCF_i-=eaochT0dd2BN9CQ@mail.gmail.com
2019-03-12 12:30:35 -04:00
Tom Lane a6417078c4 Create a script that can renumber manually-assigned OIDs.
This commit adds a Perl script renumber_oids.pl, which can reassign a
range of manually-assigned OIDs to someplace else by modifying OID
fields of the catalog *.dat files and OID-assigning macros in the
catalog *.h files.

Up to now, we've encouraged new patches that need manually-assigned
OIDs to use OIDs just above the range of existing OIDs.  Predictably,
this leads to patches stepping on each others' toes, as whichever
one gets committed first creates an OID conflict that other patch
author(s) have to resolve manually.  With the availability of
renumber_oids.pl, we can eliminate a lot of this hassle.
The new project policy, therefore, is:

* Encourage new patches to use high OIDs (the documentation suggests
choosing a block of OIDs at random in 8000..9999).

* After feature freeze in each development cycle, run renumber_oids.pl
to move all such OIDs down to lower numbers, thus freeing the high OID
range for the next development cycle.

This plan should greatly reduce the risk of OID collisions between
concurrently-developed patches.  Also, if such a collision happens
anyway, we have the option to resolve it without much effort by doing
an off-schedule OID renumbering to get the first-committed patch out
of the way.  Or a patch author could use renumber_oids.pl to change
their patch's assignments without much pain.

This approach does put a premium on not hard-wiring any OID values
in places where renumber_oids.pl and genbki.pl can't fix them.
Project practice in that respect seems to be pretty good already,
but a follow-on patch will sand down some rough edges.

John Naylor and Tom Lane, per an idea of Peter Geoghegan's

Discussion: https://postgr.es/m/CAH2-WzmMTGMcPuph4OvsO7Ykut0AOCF_i-=eaochT0dd2BN9CQ@mail.gmail.com
2019-03-12 10:50:48 -04:00
Tom Lane 1a83a80a2f Allow fractional input values for integer GUCs, and improve rounding logic.
Historically guc.c has just refused examples like set work_mem = '30.1GB',
but it seems more useful for it to take that and round off the value to
some reasonable approximation of what the user said.  Just rounding to
the parameter's native unit would work, but it would lead to rather
silly-looking settings, such as 31562138kB for this example.  Instead
let's round to the nearest multiple of the next smaller unit (if any),
producing 30822MB.

Also, do the units conversion math in floating point and round to integer
(if needed) only at the end.  This produces saner results for inputs that
aren't exact multiples of the parameter's native unit, and removes another
difference in the behavior for integer vs. float parameters.

In passing, document the ability to use hex or octal input where it
ought to be documented.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
2019-03-11 19:13:55 -04:00
Andrew Dunstan fe0b2c12c9 Tweak wording on VARIADIC array doc patch.
Per suggestion from Tom Lane.
2019-03-11 18:23:01 -04:00
Andrew Dunstan 5e74a42785 Document incompatibility of comparison expressions with VARIADIC array arguments
COALESCE, GREATEST and LEAST all look like functions taking variable
numbers of arguments, but in fact they are not functions, and so
VARIADIC array arguments don't work with them. Add a note to the docs
explaining this fact.

The consensus is not to try to make this work, but just to document the
limitation.

Discussion: https://postgr.es/m/CAFj8pRCaAtuXuRtvXf5GmPbAVriUQrNMo7-=TXUFN025S31R_w@mail.gmail.com
2019-03-11 18:14:05 -04:00
Andrew Dunstan a478415281 pgbench: increase the maximum number of variables/arguments
pgbench's arbitrary limit of 10 arguments for SQL statements or
metacommands is far too low. Increase it to 256.

This results in a very modest increase in memory usage, not enough to
worry about.

The maximum includes the SQL statement or metacommand. This is reflected
in the comments and revised TAP tests.

Simon Riggs and Dagfinn Ilmari Mannsåker with some light editing by me.
Reviewed by: David Rowley and Fabien Coelho

Discussion: https://postgr.es/m/CANP8+jJiMJOAf-dLoHuR-8GENiK+eHTY=Omw38Qx7j2g0NDTXA@mail.gmail.com
2019-03-11 13:18:37 -04:00
Alvaro Herrera fc84c05acd Fix documentation on partitioning vs. foreign tables
1. The PARTITION OF clause of CREATE FOREIGN TABLE was not explained in
   the CREATE FOREIGN TABLE reference page.  Add it.
   (Postgres 10 onwards)

2. The limitation that tuple routing cannot target partitions that are
   foreign tables was not documented clearly enough.  Improve wording.
   (Postgres 10 onwards)

3. The UPDATE tuple re-routing concurrency behavior was explained in
   the DDL chapter, which doesn't seem the right place.  Move it to the
   UPDATE reference page instead.  (Postgres 11 onwards).

Authors: Amit Langote, David Rowley.
Reviewed-by: Etsuro Fujita.
Reported-by: Derek Hans
Discussion: https://postgr.es/m/CAGrP7a3Xc1Qy_B2WJcgAD8uQTS_NDcJn06O5mtS_Ne1nYhBsyw@mail.gmail.com
2019-03-10 19:45:29 -03:00
Tom Lane cbccac371c Reduce the default value of autovacuum_vacuum_cost_delay to 2ms.
This is a better way to implement the desired change of increasing
autovacuum's default resource consumption.

Discussion: https://postgr.es/m/28720.1552101086@sss.pgh.pa.us
2019-03-10 15:16:21 -04:00
Tom Lane 52985e4fea Revert "Increase the default vacuum_cost_limit from 200 to 2000"
This reverts commit bd09503e63.

Per discussion, it seems like what we should do instead is to
reduce the default value of autovacuum_vacuum_cost_delay by the
same factor.  That's functionally equivalent as long as the
platform can accurately service the smaller delay request, which
should be true on anything released in the last 10 years or more.
And smaller, more-closely-spaced delays are better in terms of
providing a steady I/O load.

Discussion: https://postgr.es/m/28720.1552101086@sss.pgh.pa.us
2019-03-10 15:05:25 -04:00
Tom Lane caf626b2cd Convert [autovacuum_]vacuum_cost_delay into floating-point GUCs.
This change makes it possible to specify sub-millisecond delays,
which work well on most modern platforms, though that was not true
when the cost-delay feature was designed.

To support this without breaking existing configuration entries,
improve guc.c to allow floating-point GUCs to have units.  Also,
allow "us" (microseconds) as an input/output unit for time-unit GUCs.
(It's not allowed as a base unit, at least not yet.)

Likewise change the autovacuum_vacuum_cost_delay reloption to be
floating-point; this forces a catversion bump because the layout of
StdRdOptions changes.

This patch doesn't in itself change the default values or allowed
ranges for these parameters, and it should not affect the behavior
for any already-allowed setting for them.

Discussion: https://postgr.es/m/1798.1552165479@sss.pgh.pa.us
2019-03-10 15:01:39 -04:00
Alexander Korotkov f2e403803f Support for INCLUDE attributes in GiST indexes
Similarly to B-tree, GiST index access method gets support of INCLUDE
attributes.  These attributes aren't used for tree navigation and aren't
present in non-leaf pages.  But they are present in leaf pages and can be
fetched during index-only scan.

The point of having INCLUDE attributes in GiST indexes is slightly different
from the point of having them in B-tree.  The main point of INCLUDE attributes
in B-tree is to define UNIQUE constraint over part of attributes enabled for
index-only scan.  In GiST the main point of INCLUDE attributes is to use
index-only scan for attributes, whose data types don't have GiST opclasses.

Discussion: https://postgr.es/m/73A1A452-AD5F-40D4-BD61-978622FF75C1%40yandex-team.ru
Author: Andrey Borodin, with small changes by me
Reviewed-by: Andreas Karlsson
2019-03-10 11:37:17 +03:00
Tom Lane a0b7626268 Simplify release-note links to back branches.
Now that https://www.postgresql.org/docs/release/ is populated,
replace the stopgap text we had under "Prior Releases" with
a pointer to that archive.

Discussion: https://postgr.es/m/e0f09c9a-bd2b-862a-d379-601dfabc8969@postgresql.org
2019-03-09 18:42:39 -05:00
Magnus Hagander 0516c61b75 Add new clientcert hba option verify-full
This allows a login to require both that the cn of the certificate
matches (like authentication type cert) *and* that another
authentication method (such as password or kerberos) succeeds as well.

The old value of clientcert=1 maps to the new clientcert=verify-ca,
clientcert=0 maps to the new clientcert=no-verify, and the new option
erify-full will add the validation of the CN.

Author: Julian Markwort, Marius Timmer
Reviewed by: Magnus Hagander, Thomas Munro
2019-03-09 12:19:47 -08:00
Magnus Hagander 6b9e875f72 Track block level checksum failures in pg_stat_database
This adds a column that counts how many checksum failures have occurred
on files belonging to a specific database. Both checksum failures
during normal backend processing and those created when a base backup
detects a checksum failure are counted.

Author: Magnus Hagander
Reviewed by: Julien Rouhaud
2019-03-09 10:47:30 -08:00
Michael Paquier e1e0e8d58c Fix function signatures of pageinspect in documentation
tuple_data_split() lacked the type of the first argument, and
heap_page_item_attrs() has reversed the first and second argument,
with the bytea argument using an incorrect name.

Author: Laurenz Albe
Discussion: https://postgr.es/m/8f9ab7b16daf623e87eeef5203a4ffc0dece8dfd.camel@cybertec.at
Backpatch-through: 9.6
2019-03-08 15:10:14 +09:00
Alvaro Herrera 251cf2e27b Fix minor deficiencies in XMLTABLE, xpath(), xmlexists()
Correctly process nodes of more types than previously.  In some cases,
nodes were being ignored (nothing was output); in other cases, trying to
return them resulted in errors about unrecognized nodes.  In yet other
cases, necessary escaping (of XML special characters) was not being
done.  Fix all those (as far as the authors could find) and add
regression tests cases verifying the new behavior.

I (Álvaro) was of two minds about backpatching these changes.  They do
seem bugfixes that would benefit most users of the affected functions;
but on the other hand it would change established behavior in minor
releases, so it seems prudent not to.

Authors: Pavel Stehule, Markus Winand, Chapman Flack
Discussion:
   https://postgr.es/m/CAFj8pRA6J25CtAZ2TuRvxK3gat7-bBUYh0rfE2yM7Hj9GD14Dg@mail.gmail.com
   https://postgr.es/m/8BDB0627-2105-4564-AA76-7849F028B96E@winand.at

The elephant in the room as pointed out by Chapman Flack, not fixed in
this commit, is that we still have XMLTABLE operating on XPath 1.0
instead of the standard-mandated XQuery (or even its subset XPath 2.0).
Fixing that is a major undertaking, however.
2019-03-07 18:16:34 -03:00
Robert Haas 898e5e3290 Allow ATTACH PARTITION with only ShareUpdateExclusiveLock.
We still require AccessExclusiveLock on the partition itself, because
otherwise an insert that violates the newly-imposed partition
constraint could be in progress at the same time that we're changing
that constraint; only the lock level on the parent relation is
weakened.

To make this safe, we have to cope with (at least) three separate
problems. First, relevant DDL might commit while we're in the process
of building a PartitionDesc.  If so, find_inheritance_children() might
see a new partition while the RELOID system cache still has the old
partition bound cached, and even before invalidation messages have
been queued.  To fix that, if we see that the pg_class tuple seems to
be missing or to have a null relpartbound, refetch the value directly
from the table. We can't get the wrong value, because DETACH PARTITION
still requires AccessExclusiveLock throughout; if we ever want to
change that, this will need more thought. In testing, I found it quite
difficult to hit even the null-relpartbound case; the race condition
is extremely tight, but the theoretical risk is there.

Second, successive calls to RelationGetPartitionDesc might not return
the same answer.  The query planner will get confused if lookup up the
PartitionDesc for a particular relation does not return a consistent
answer for the entire duration of query planning.  Likewise, query
execution will get confused if the same relation seems to have a
different PartitionDesc at different times.  Invent a new
PartitionDirectory concept and use it to ensure consistency.  This
ensures that a single invocation of either the planner or the executor
sees the same view of the PartitionDesc from beginning to end, but it
does not guarantee that the planner and the executor see the same
view.  Since this allows pointers to old PartitionDesc entries to
survive even after a relcache rebuild, also postpone removing the old
PartitionDesc entry until we're certain no one is using it.

For the most part, it seems to be OK for the planner and executor to
have different views of the PartitionDesc, because the executor will
just ignore any concurrently added partitions which were unknown at
plan time; those partitions won't be part of the inheritance
expansion, but invalidation messages will trigger replanning at some
point.  Normally, this happens by the time the very next command is
executed, but if the next command acquires no locks and executes a
prepared query, it can manage not to notice until a new transaction is
started.  We might want to tighten that up, but it's material for a
separate patch.  There would still be a small window where a query
that started just after an ATTACH PARTITION command committed might
fail to notice its results -- but only if the command starts before
the commit has been acknowledged to the user. All in all, the warts
here around serializability seem small enough to be worth accepting
for the considerable advantage of being able to add partitions without
a full table lock.

Although in general the consequences of new partitions showing up
between planning and execution are limited to the query not noticing
the new partitions, run-time partition pruning will get confused in
that case, so that's the third problem that this patch fixes.
Run-time partition pruning assumes that indexes into the PartitionDesc
are stable between planning and execution.  So, add code so that if
new partitions are added between plan time and execution time, the
indexes stored in the subplan_map[] and subpart_map[] arrays within
the plan's PartitionedRelPruneInfo get adjusted accordingly.  There
does not seem to be a simple way to generalize this scheme to cope
with partitions that are removed, mostly because they could then get
added back again with different bounds, but it works OK for added
partitions.

This code does not try to ensure that every backend participating in
a parallel query sees the same view of the PartitionDesc.  That
currently doesn't matter, because we never pass PartitionDesc
indexes between backends.  Each backend will ignore the concurrently
added partitions which it notices, and it doesn't matter if different
backends are ignoring different sets of concurrently added partitions.
If in the future that matters, for example because we allow writes in
parallel query and want all participants to do tuple routing to the same
set of partitions, the PartitionDirectory concept could be improved to
share PartitionDescs across backends.  There is a draft patch to
serialize and restore PartitionDescs on the thread where this patch
was discussed, which may be a useful place to start.

Patch by me.  Thanks to Alvaro Herrera, David Rowley, Simon Riggs,
Amit Langote, and Michael Paquier for discussion, and to Alvaro
Herrera for some review.

Discussion: http://postgr.es/m/CA+Tgmobt2upbSocvvDej3yzokd7AkiT+PvgFH+a9-5VV1oJNSQ@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoZE0r9-cyA-aY6f8WFEROaDLLL7Vf81kZ8MtFCkxpeQSw@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoY13KQZF-=HNTrt9UYWYx3_oYOQpu9ioNT49jGgiDpUEA@mail.gmail.com
2019-03-07 11:13:12 -05:00
Alvaro Herrera ec51727f6e Fix broken markup 2019-03-07 11:35:39 -03:00
Alvaro Herrera eaaa5986ad Fix the BY {REF,VALUE} clause of XMLEXISTS/XMLTABLE
This clause is used to indicate the passing mode of a XML document, but
we were doing it wrong: we accepted BY REF and ignored it, and rejected
BY VALUE as a syntax error.  The reality, however, is that documents are
always passed BY VALUE, so rejecting that clause was silly.  Change
things so that we accept BY VALUE.

BY REF continues to be accepted, and continues to be ignored.

Author: Chapman Flack
Reviewed-by: Pavel Stehule
Discussion: https://postgr.es/m/5C297BB7.9070509@anastigmatix.net
2019-03-07 11:20:35 -03:00
Alvaro Herrera 7e413a0f82 pg_dump: allow multiple rows per insert
This is useful to speed up loading data in a different database engine.

Authors: Surafel Temesgen and David Rowley.  Lightly edited by Álvaro.
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/CALAY4q9kumSdnRBzvRJvSRf2+BH20YmSvzqOkvwpEmodD-xv6g@mail.gmail.com
2019-03-07 09:34:17 -03:00
Andres Freund 8586bf7ed8 tableam: introduce table AM infrastructure.
This introduces the concept of table access methods, i.e. CREATE
  ACCESS METHOD ... TYPE TABLE and
  CREATE TABLE ... USING (storage-engine).
No table access functionality is delegated to table AMs as of this
commit, that'll be done in following commits.

Subsequent commits will incrementally abstract table access
functionality to be routed through table access methods. That change
is too large to be reviewed & committed at once, so it'll be done
incrementally.

Docs will be updated at the end, as adding them incrementally would
likely make them less coherent, and definitely is a lot more work,
without a lot of benefit.

Table access methods are specified similar to index access methods,
i.e. pg_am.amhandler returns, as INTERNAL, a pointer to a struct with
callbacks. In contrast to index AMs that struct needs to live as long
as a backend, typically that's achieved by just returning a pointer to
a constant struct.

Psql's \d+ now displays a table's access method. That can be disabled
with HIDE_TABLEAM=true, which is mainly useful so regression tests can
be run against different AMs.  It's quite possible that this behaviour
still needs to be fine tuned.

For now it's not allowed to set a table AM for a partitioned table, as
we've not resolved how partitions would inherit that. Disallowing
allows us to introduce, if we decide that's the way forward, such a
behaviour without a compatibility break.

Catversion bumped, to add the heap table AM and references to it.

Author: Haribabu Kommi, Andres Freund, Alvaro Herrera, Dimitri Golgov and others
Discussion:
    https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
    https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
    https://postgr.es/m/20190107235616.6lur25ph22u5u5av@alap3.anarazel.de
    https://postgr.es/m/20190304234700.w5tmhducs5wxgzls@alap3.anarazel.de
2019-03-06 09:54:38 -08:00
Andrew Dunstan bd09503e63 Increase the default vacuum_cost_limit from 200 to 2000
The original 200 default value was set back in f425b605f4 when the cost
delay settings were first added.  Hardware has improved quite a bit since
then and we've also made improvements such as sorting buffers during
checkpoints (9cd00c457e) which should result in less random writes.

This low default value was reportedly causing problems with badly
configured servers and in the absence of a native method to remove
excessive bloat from tables without incurring an AccessExclusiveLock, this
often made cleaning up the damage caused by badly configured auto-vacuums
difficult.

It seems more likely that someone will notice that auto-vacuum is running
too quickly than too slowly, so let's go all out and multiple the default
value for the setting by 10.  With the default vacuum_cost_page_dirty and
autovacuum_vacuum_cost_delay (assuming a page size of 8192 bytes), this
allows autovacuum a theoretical maximum dirty write rate of around 39MB/s
instead of just 3.9MB/s.

Author: David Rowley

Discussion: https://postgr.es/m/CAKJS1f_YbXC2qTMPyCbmsPiKvZYwpuQNQMohiRXLj1r=8_rYvw@mail.gmail.com
2019-03-06 09:10:12 -05:00
Alvaro Herrera b96f6b1948 pg_partition_ancestors
Adds another introspection feature for partitioning, necessary for
further psql patches.

Reviewed-by: Michaël Paquier
Discussion: https://postgr.es/m/20190226222757.GA31622@alvherre.pgsql
2019-03-04 16:14:29 -03:00
Andres Freund ad0bda5d24 Store tuples for EvalPlanQual in slots, rather than as HeapTuples.
For the upcoming pluggable table access methods it's quite
inconvenient to store tuples as HeapTuples, as that'd require
converting tuples from a their native format into HeapTuples. Instead
use slots to manage epq tuples.

To fit into that scheme, change the foreign data wrapper callback
RefetchForeignRow, to store the tuple in a slot. Insist on using the
caller provided slot, so it conveniently can be stored in the
corresponding EPQ slot.  As there is no in core user of
RefetchForeignRow, that change was done blindly, but we plan to test
that soon.

To avoid duplicating that work for row locks, move row locks to just
directly use the EPQ slots - it previously temporarily stored tuples
in LockRowsState.lr_curtuples, but that doesn't seem beneficial, given
we'd possibly end up with a significant number of additional slots.

The behaviour of es_epqTupleSet[rti -1] is now checked by
es_epqTupleSlot[rti -1] != NULL, as that is distinguishable from a
slot containing an empty tuple.

Author: Andres Freund, Haribabu Kommi, Ashutosh Bapat
Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
2019-03-01 10:37:57 -08:00
Andrew Dunstan f092de0503 Add --exclude-database option to pg_dumpall
This option functions similarly to pg_dump's --exclude-table option, but
for database names. The option can be given once, and the argument can
be a pattern including wildcard characters.

Author: Andrew Dunstan.
Reviewd-by: Fabien Coelho and Michael Paquier
Discussion: https://postgr.es/m/43a54a47-4aa7-c70e-9ca6-648f436dd6e6@2ndQuadrant.com
2019-03-01 10:47:44 -05:00
Alvaro Herrera 2c31825fb9 Improve docs for ALTER TABLE .. SET TABLESPACE
Discussion: https://postgr.es/m/20190220173815.GA7959@alvherre.pgsql
Reviewed-by: Robert Haas
2019-02-28 19:24:21 -03:00
Michael Paquier b3a156858a Improve documentation of data_sync_retry
Reflecting an updated parameter value requires a server restart, which
was not mentioned in the documentation and in postgresql.conf.sample.

Reported-by: Thomas Poty
Discussion: https://postgr.es/m/15659-0cd812f13027a2d8@postgresql.org
2019-02-28 11:02:11 +09:00
Peter Eisentraut 6ae578a91e Set fallback_application_name for a walreceiver to cluster_name
By default, the fallback_application_name for a physical walreceiver
is "walreceiver".  This means that multiple standbys cannot be
distinguished easily on a primary, for example in pg_stat_activity or
synchronous_standby_names.

If cluster_name is set, use that for fallback_application_name in the
walreceiver.  (If it's not set, it remains "walreceiver".)  If someone
set cluster_name to identify their instance, we might as well use that
by default to identify the node remotely as well.  It's still possible
to specify another application_name in primary_conninfo explicitly.

Reviewed-by: Euler Taveira <euler@timbira.com.br>
Discussion: https://www.postgresql.org/message-id/flat/1257eaee-4874-e791-e83a-46720c72cac7@2ndquadrant.com
2019-02-27 10:59:25 +01:00
Peter Eisentraut bc09d5e4cc Remove unnecessary use of PROCEDURAL
Remove some unnecessary, legacy-looking use of the PROCEDURAL keyword
before LANGUAGE.  We mostly don't use this anymore, so some of these
look a bit old.

There is still some use in pg_dump, which is harder to remove because
it's baked into the archive format, so I'm not touching that.

Discussion: https://www.postgresql.org/message-id/2330919b-62d9-29ac-8de3-58c024fdcb96@2ndquadrant.com
2019-02-25 08:38:59 +01:00
Peter Eisentraut 213eae9b8a doc: Add security information about pg_stat_activity
Add a basic note that some columns in pg_stat_activity and related
views are not visible to all users.

Discussion: https://www.postgresql.org/message-id/3018acd9-e5d8-1e85-5ed7-47276cd77569%402ndquadrant.com
2019-02-21 19:49:27 +01:00
Peter Eisentraut 7aa00d2464 Fix dbtoepub output file name
In previous releases, the input file of dbtoepub was postgres.xml, and
dbtoepub knows to derive the output file name postgres.epub from that
automatically.  But now the intput file is postgres.sgml (since
postgres.sgml is itself an XML file and we no longer need the
intermediate postgres.xml file), but dbtoepub doesn't know how to deal
with the .sgml suffix, so the automatically derived output file name
becomes postgres.sgml.epub.  Fix by adding an explicit -o option.
2019-02-21 15:43:28 +01:00
Amit Kapila 29d108cdec Doc: Update the documentation for FSM behavior for small tables.
In commit b0eaa4c51b, we have avoided the creation of FSM for small tables.
So the functions that use FSM to compute the free space can return zero for
such tables.  This was previously also possible for the cases where the
vacuum has not been triggered to update FSM.

This commit updates the comments in code and documentation to reflect this
behavior.

Author: John Naylor
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CACPNZCtba-3m1q3A8gxA_vxg=T7gQf7gMbpR4Ciy5LntY-j+0Q@mail.gmail.com
2019-02-20 17:37:39 +05:30
Andrew Dunstan af25bc03e1 Provide an extra-float-digits setting for pg_dump / pg_dumpall
Changes made by commit 02ddd49 mean that dumps made against pre version
12 instances are no longer comparable with those made against version 12
or later instances. This makes cross-version upgrade testing fail in the
buildfarm. Experimentation has shown that the error is cured if the
dumps are made when extra_float_digits is set to 0. Hence this patch
allows for it to be explicitly set rather than relying on pg_dump's
builtin default (3 in almost all cases). This feature might have other
uses, but should not normally be used.

Discussion: https://postgr.es/m/c76f7051-8fd3-ec10-7579-1f8842305b85@2ndQuadrant.com
2019-02-18 07:37:07 -05:00
Michael Meskes 050710b369 Add bytea datatype to ECPG.
So far ECPG programs had to treat binary data for bytea column as 'char' type.
But this meant converting from/to escaped format with PQunescapeBytea/
PQescapeBytea() and therefore forcing users to add unnecessary code and cost
for the conversion in runtime. By adding a dedicated datatype for bytea most of
this special handling is no longer needed.

Author: Matsumura-san ("Matsumura, Ryo" <matsumura.ryo@jp.fujitsu.com>)

Discussion: https://postgr.es/m/flat/03040DFF97E6E54E88D3BFEE5F5480F737A141F9@G01JPEXMBYT04
2019-02-18 10:20:31 +01:00
Joe Conway bc6d7eb689 Fix documentation for dblink_error_message() return value
The dblink documentation claims that an empty string is returned if there
has been no error, however OK is actually returned in that case. Also,
clarify that an async error may not be seen unless dblink_is_busy() or
dblink_get_result() have been called first.

Backpatch to all supported branches.

Reported-by: realyota
Backpatch-through: 9.4
Discussion: https://postgr.es/m/153371978486.1298.2091761143788088262@wrigleys.postgresql.org
2019-02-17 13:17:34 -05:00
Tatsuo Ishii 69e5247879 Doc: remove ancient comment.
There's a very old comment in rules.sgml added back to 2003.  It
expected to a feature coming back but it never happened. So now we can
safely remove the comment. Back-patched to all supported branches.

Discussion: https://postgr.es/m/20190211.191004.219630835457494660.t-ishii%40sraoss.co.jp
2019-02-17 20:23:10 +09:00
Noah Misch 301de4f7d9 Fix CLogTruncationLock documentation.
Back-patch to v10, which introduced the lock.
2019-02-17 00:51:11 -08:00
Andrew Gierth 6ee89952d4 Remove float8-small-is-zero regression test variant.
Since this was also the variant used as an example in the docs, update
the docs to use float4-misrounded-input as an example instead, since
that is now the only remaining variant file.
2019-02-16 22:11:04 +00:00
Tom Lane 608b167f9f Allow user control of CTE materialization, and change the default behavior.
Historically we've always materialized the full output of a CTE query,
treating WITH as an optimization fence (so that, for example, restrictions
from the outer query cannot be pushed into it).  This is appropriate when
the CTE query is INSERT/UPDATE/DELETE, or is recursive; but when the CTE
query is non-recursive and side-effect-free, there's no hazard of changing
the query results by pushing restrictions down.

Another argument for materialization is that it can avoid duplicate
computation of an expensive WITH query --- but that only applies if
the WITH query is called more than once in the outer query.  Even then
it could still be a net loss, if each call has restrictions that
would allow just a small part of the WITH query to be computed.

Hence, let's change the behavior for WITH queries that are non-recursive
and side-effect-free.  By default, we will inline them into the outer
query (removing the optimization fence) if they are called just once.
If they are called more than once, we will keep the old behavior by
default, but the user can override this and force inlining by specifying
NOT MATERIALIZED.  Lastly, the user can force the old behavior by
specifying MATERIALIZED; this would mainly be useful when the query had
deliberately been employing WITH as an optimization fence to prevent a
poor choice of plan.

Andreas Karlsson, Andrew Gierth, David Fetter

Discussion: https://postgr.es/m/87sh48ffhb.fsf@news-spur.riddles.org.uk
2019-02-16 16:11:12 -05:00
Michael Meskes bd7c95f0c1 Add DECLARE STATEMENT support to ECPG.
DECLARE STATEMENT is a statement that lets users declare an identifier
pointing at a connection.  This identifier will be used in other embedded
dynamic SQL statement such as PREPARE, EXECUTE, DECLARE CURSOR and so on.
When connecting to a non-default connection, the AT clause can be used in
a DECLARE STATEMENT once and is no longer needed in every dynamic SQL
statement.  This makes ECPG applications easier and more efficient.  Moreover,
writing code without designating connection explicitly improves portability.

Authors: Ideriha-san ("Ideriha, Takeshi" <ideriha.takeshi@jp.fujitsu.com>)
         Kuroda-san ("Kuroda, Hayato" <kuroda.hayato@jp.fujitsu.com>)

Discussion: https://postgr.es/m4E72940DA2BF16479384A86D54D0988A565669DF@G01JPEXMBKW04
2019-02-16 11:05:54 +01:00