Commit Graph

1594 Commits

Author SHA1 Message Date
Robert Haas b648b70342 Speed up CREATE INDEX CONCURRENTLY's TID sort.
Encode TIDs as 64-bit integers to speed up comparisons.  This seems to
speed things up on all platforms, but is even more beneficial when
8-byte integers are passed by value.

Peter Geoghegan.  Design suggestions and review by Tom Lane.  Review
also by Simon Riggs and by me.
2015-12-16 15:23:45 -05:00
Robert Haas f27a6b15e6 Mark CHECK constraints declared NOT VALID valid if created with table.
FOREIGN KEY constraints have behaved this way for a long time, but for
some reason the behavior of CHECK constraints has been inconsistent up
until now.

Amit Langote and Amul Sul, with assorted tweaks by me.
2015-12-16 07:43:56 -05:00
Alvaro Herrera 8c1615531f For REASSIGN OWNED for foreign user mappings
As reported in bug #13809 by Alexander Ashurkov, the code for REASSIGN
OWNED hadn't gotten word about user mappings.  Deal with them in the
same way default ACLs do, which is to ignore them altogether; they are
handled just fine by DROP OWNED.  The other foreign object cases are
already handled correctly by both commands.

Also add a REASSIGN OWNED statement to foreign_data test to exercise the
foreign data objects.  (The changes are just before the "cleanup" phase,
so it shouldn't remove any existing live test.)

Reported by Alexander Ashurkov, then independently by Jaime Casanova.
2015-12-11 18:39:09 -03:00
Stephen Frost 833728d4c8 Handle policies during DROP OWNED BY
DROP OWNED BY handled GRANT-based ACLs but was not removing roles from
policies.  Fix that by having DROP OWNED BY remove the role specified
from the list of roles the policy (or policies) apply to, or the entire
policy (or policies) if it only applied to the role specified.

As with ACLs, the DROP OWNED BY caller must have permission to modify
the policy or a WARNING is thrown and no change is made to the policy.
2015-12-11 16:12:25 -05:00
Peter Eisentraut a351705d8a Improve some messages 2015-12-10 22:05:27 -05:00
Tom Lane 074c5cfbfb Fix handling of inherited check constraints in ALTER COLUMN TYPE (again).
The previous way of reconstructing check constraints was to do a separate
"ALTER TABLE ONLY tab ADD CONSTRAINT" for each table in an inheritance
hierarchy.  However, that way has no hope of reconstructing the check
constraints' own inheritance properties correctly, as pointed out in
bug #13779 from Jan Dirk Zijlstra.  What we should do instead is to do
a regular "ALTER TABLE", allowing recursion, at the topmost table that
has a particular constraint, and then suppress the work queue entries
for inherited instances of the constraint.

Annoyingly, we'd tried to fix this behavior before, in commit 5ed6546cf,
but we failed to notice that it wasn't reconstructing the pg_constraint
field values correctly.

As long as I'm touching pg_get_constraintdef_worker anyway, tweak it to
always schema-qualify the target table name; this seems like useful backup
to the protections installed by commit 5f173040.

In HEAD/9.5, get rid of get_constraint_relation_oids, which is now unused.
(I could alternatively have modified it to also return conislocal, but that
seemed like a pretty single-purpose API, so let's not pretend it has some
other use.)  It's unused in the back branches as well, but I left it in
place just in case some third-party code has decided to use it.

In HEAD/9.5, also rename pg_get_constraintdef_string to
pg_get_constraintdef_command, as the previous name did nothing to explain
what that entry point did differently from others (and its comment was
equally useless).  Again, that change doesn't seem like material for
back-patching.

I did a bit of re-pgindenting in tablecmds.c in HEAD/9.5, as well.

Otherwise, back-patch to all supported branches.
2015-11-20 14:55:47 -05:00
Robert Haas fea2b642fd Remove numbers from incorrectly-numbered list.
Reported by Andres Freund.
2015-11-19 16:45:13 -05:00
Robert Haas bc4996e61b Make ALTER .. SET SCHEMA do nothing, instead of throwing an ERROR.
This was already true for CREATE EXTENSION, but historically has not
been true for other object types.  Therefore, this is a backward
incompatibility.  Per discussion on pgsql-hackers, everyone seems to
agree that the new behavior is better.

Marti Raudsepp, reviewed by Haribabu Kommi and myself
2015-11-19 10:49:25 -05:00
Peter Eisentraut 5db837d3f2 Message improvements 2015-11-16 21:39:23 -05:00
Peter Eisentraut a8d585c091 Message style improvements
Message style, plurals, quoting, spelling, consistency with similar
messages
2015-10-28 20:38:36 -04:00
Stephen Frost 088c83363a ALTER TABLE .. FORCE ROW LEVEL SECURITY
To allow users to force RLS to always be applied, even for table owners,
add ALTER TABLE .. FORCE ROW LEVEL SECURITY.

row_security=off overrides FORCE ROW LEVEL SECURITY, to ensure pg_dump
output is complete (by default).

Also add SECURITY_NOFORCE_RLS context to avoid data corruption when
ALTER TABLE .. FORCE ROW SECURITY is being used. The
SECURITY_NOFORCE_RLS security context is used only during referential
integrity checks and is only considered in check_enable_rls() after we
have already checked that the current user is the owner of the relation
(which should always be the case during referential integrity checks).

Back-patch to 9.5 where RLS was added.
2015-10-04 21:05:08 -04:00
Robert Haas 7aea8e4f2d Determine whether it's safe to attempt a parallel plan for a query.
Commit 924bcf4f16 introduced a framework
for parallel computation in PostgreSQL that makes most but not all
built-in functions safe to execute in parallel mode.  In order to have
parallel query, we'll need to be able to determine whether that query
contains functions (either built-in or user-defined) that cannot be
safely executed in parallel mode.  This requires those functions to be
labeled, so this patch introduces an infrastructure for that.  Some
functions currently labeled as safe may need to be revised depending on
how pending issues related to heavyweight locking under paralllelism
are resolved.

Parallel plans can't be used except for the case where the query will
run to completion.  If portal execution were suspended, the parallel
mode restrictions would need to remain in effect during that time, but
that might make other queries fail.  Therefore, this patch introduces
a framework that enables consideration of parallel plans only when it
is known that the plan will be run to completion.  This probably needs
some refinement; for example, at bind time, we do not know whether a
query run via the extended protocol will be execution to completion or
run with a limited fetch count.  Having the client indicate its
intentions at bind time would constitute a wire protocol break.  Some
contexts in which parallel mode would be safe are not adjusted by this
patch; the default is not to try parallel plans except from call sites
that have been updated to say that such plans are OK.

This commit doesn't introduce any parallel paths or plans; it just
provides a way to determine whether they could potentially be used.
I'm committing it on the theory that the remaining parallel sequential
scan patches will also get committed to this release, hopefully in the
not-too-distant future.

Robert Haas and Amit Kapila.  Reviewed (in earlier versions) by Noah
Misch.
2015-09-16 15:38:47 -04:00
Peter Eisentraut b2ae8f1e35 Update SQL features list 2015-09-12 00:08:18 -04:00
Andres Freund 6fcd88511f Allow pg_create_physical_replication_slot() to reserve WAL.
When creating a physical slot it's often useful to immediately reserve
the current WAL position instead of only doing after the first feedback
message arrives. That e.g. allows slots to guarantee that all the WAL
for a base backup will be available afterwards.

Logical slots already have to reserve WAL during creation, so generalize
that logic into being usable for both physical and logical slots.

Catversion bump because of the new parameter.

Author: Gurjeet Singh
Reviewed-By: Andres Freund
Discussion: CABwTF4Wh_dBCzTU=49pFXR6coR4NW1ynb+vBqT+Po=7fuq5iCw@mail.gmail.com
2015-08-11 12:34:31 +02:00
Andres Freund 3f811c2d6f Add confirmed_flush column to pg_replication_slots.
There's no reason not to expose both restart_lsn and confirmed_flush
since they have rather distinct meanings. The former is the oldest WAL
still required and valid for both physical and logical slots, whereas
the latter is the location up to which a logical slot's consumer has
confirmed receiving data. Most of the time a slot will require older
WAL (i.e. restart_lsn) than the confirmed
position (i.e. confirmed_flush_lsn).

Author: Marko Tiikkaja, editorialized by me
Discussion: 559D110B.1020109@joh.to
2015-08-10 13:28:18 +02:00
Alvaro Herrera 2834855cb9 Fix BRIN to use SnapshotAny during summarization
For correctness of summarization results, it is critical that the
snapshot used during the summarization scan is able to see all tuples
that are live to all transactions -- including tuples inserted or
deleted by in-progress transactions.  Otherwise, it would be possible
for a transaction to insert a tuple, then idle for a long time while a
concurrent transaction executes summarization of the range: this would
result in the inserted value not being considered in the summary.
Previously we were trying to use a MVCC snapshot in conjunction with
adding a "placeholder" tuple in the index: the snapshot would see all
committed tuples, and the placeholder tuple would catch insertions by
any new inserters.  The hole is that prior insertions by transactions
that are still in progress by the time the MVCC snapshot was taken were
ignored.

Kevin Grittner reported this as a bogus error message during vacuum with
default transaction isolation mode set to repeatable read (because the
error report mentioned a function name not being invoked during), but
the problem is larger than that.

To fix, tweak IndexBuildHeapRangeScan to have a new mode that behaves
the way we need using SnapshotAny visibility rules.  This change
simplifies the BRIN code a bit, mainly by removing large comments that
were mistaken.  Instead, rely on the SnapshotAny semantics to provide
what it needs.  (The business about a placeholder tuple needs to remain:
that covers the case that a transaction inserts a a tuple in a page that
summarization already scanned.)

Discussion: https://www.postgresql.org/message-id/20150731175700.GX2441@postgresql.org

In passing, remove a couple of unused declarations from brin.h and
reword a comment to be proper English.  This part submitted by Kevin
Grittner.

Backpatch to 9.5, where BRIN was introduced.
2015-08-05 16:20:50 -03:00
Joe Conway f781a0f1d8 Create a pg_shdepend entry for each role in TO clause of policies.
CreatePolicy() and AlterPolicy() omit to create a pg_shdepend entry for
each role in the TO clause. Fix this by creating a new shared dependency
type called SHARED_DEPENDENCY_POLICY and assigning it to each role.

Reported by Noah Misch. Patch by me, reviewed by Alvaro Herrera.
Back-patch to 9.5 where RLS was introduced.
2015-07-28 16:01:53 -07:00
Joe Conway 7b4bfc87d5 Plug RLS related information leak in pg_stats view.
The pg_stats view is supposed to be restricted to only show rows
about tables the user can read. However, it sometimes can leak
information which could not otherwise be seen when row level security
is enabled. Fix that by not showing pg_stats rows to users that would
be subject to RLS on the table the row is related to. This is done
by creating/using the newly introduced SQL visible function,
row_security_active().

Along the way, clean up three call sites of check_enable_rls(). The second
argument of that function should only be specified as other than
InvalidOid when we are checking as a different user than the current one,
as in when querying through a view. These sites were passing GetUserId()
instead of InvalidOid, which can cause the function to return incorrect
results if the current user has the BYPASSRLS privilege and row_security
has been set to OFF.

Additionally fix a bug causing RI Trigger error messages to unintentionally
leak information when RLS is enabled, and other minor cleanup and
improvements. Also add WITH (security_barrier) to the definition of pg_stats.

Bumped CATVERSION due to new SQL functions and pg_stats view definition.

Back-patch to 9.5 where RLS was introduced. Reported by Yaroslav.
Patch by Joe Conway and Dean Rasheed with review and input by
Michael Paquier and Stephen Frost.
2015-07-28 13:21:22 -07:00
Tom Lane dd7a8f66ed Redesign tablesample method API, and do extensive code review.
The original implementation of TABLESAMPLE modeled the tablesample method
API on index access methods, which wasn't a good choice because, without
specialized DDL commands, there's no way to build an extension that can
implement a TSM.  (Raw inserts into system catalogs are not an acceptable
thing to do, because we can't undo them during DROP EXTENSION, nor will
pg_upgrade behave sanely.)  Instead adopt an API more like procedural
language handlers or foreign data wrappers, wherein the only SQL-level
support object needed is a single handler function identified by having
a special return type.  This lets us get rid of the supporting catalog
altogether, so that no custom DDL support is needed for the feature.

Adjust the API so that it can support non-constant tablesample arguments
(the original coding assumed we could evaluate the argument expressions at
ExecInitSampleScan time, which is undesirable even if it weren't outright
unsafe), and discourage sampling methods from looking at invisible tuples.
Make sure that the BERNOULLI and SYSTEM methods are genuinely repeatable
within and across queries, as required by the SQL standard, and deal more
honestly with methods that can't support that requirement.

Make a full code-review pass over the tablesample additions, and fix
assorted bugs, omissions, infelicities, and cosmetic issues (such as
failure to put the added code stanzas in a consistent ordering).
Improve EXPLAIN's output of tablesample plans, too.

Back-patch to 9.5 so that we don't have to support the original API
in production.
2015-07-25 14:39:00 -04:00
Tom Lane 434873806a Fix some oversights in BRIN patch.
Remove HeapScanDescData.rs_initblock, which wasn't being used for anything
in the final version of the patch.

Fix IndexBuildHeapScan so that it supports syncscan again; the patch
broke synchronous scanning for index builds by forcing rs_startblk
to zero even when the caller did not care about that and had asked
for syncscan.

Add some commentary and usage defenses to heap_setscanlimits().

Fix heapam so that asking for rs_numblocks == 0 does what you would
reasonably expect.  As coded it amounted to requesting a whole-table
scan, because those "--x <= 0" tests on an unsigned variable would
behave surprisingly.
2015-07-21 13:38:24 -04:00
Alvaro Herrera 149b1dd840 Fix omission of OCLASS_TRANSFORM in object_classes[]
This was forgotten in cac7658205 (and its fixup ad89a5d115).  Since it
seems way too easy to miss this, this commit also introduces a mechanism
to enforce that the array is consistent with the enum.

Problem reported independently by Robert Haas and Jaimin Pan.
Patches proposed by Jaimin Pan, Jim Nasby, Michael Paquier and myself,
though I didn't use any of these and instead went with a cleaner
approach suggested by Tom Lane.

Backpatch to 9.5.

Discussion:
https://www.postgresql.org/message-id/CA+Tgmoa6SgDaxW_n_7SEhwBAc=mniYga+obUj5fmw4rU9_mLvA@mail.gmail.com
https://www.postgresql.org/message-id/29788.1437411581@sss.pgh.pa.us
2015-07-21 13:20:53 +02:00
Tom Lane ac50f84866 Fix misuse of TextDatumGetCString().
"TextDatumGetCString(PG_GETARG_TEXT_P(x))" is formally wrong: a text*
is not a Datum.  Although this coding will accidentally fail to fail on
all known platforms, it risks leaking memory if a detoast step is needed,
unlike "TextDatumGetCString(PG_GETARG_DATUM(x))" which is what's used
elsewhere.  Make pg_get_object_address() fall in line with other uses.

Noted while reviewing two-arg current_setting() patch.
2015-07-02 17:02:08 -04:00
Alvaro Herrera ad89a5d115 Add transforms to pg_get_object_address and friends
This was missed when transforms were added by commit cac7658205.

Extracted from a larger patch
Author: Michael Paquier
2015-06-21 16:08:49 -03:00
Andrew Dunstan 37def42245 Rename jsonb_replace to jsonb_set and allow it to add new values
The function is given a fourth parameter, which defaults to true. When
this parameter is true, if the last element of the path is missing
in the original json, jsonb_set creates it in the result and assigns it
the new value. If it is false then the function does nothing unless all
elements of the path are present, including the last.

Based on some original code from Dmitry Dolgov, heavily modified by me.

Catalog version bumped.
2015-05-31 20:34:10 -04:00
Tom Lane 17b48a1a9f Rename pg_shdepend.c's typedef "objectType" to SharedDependencyObjectType.
The name objectType is widely used as a field name, and it's pure luck that
this conflict has not caused pgindent to go crazy before.  It messed up
pg_audit.c pretty good though.  Since pg_shdepend.c doesn't export this
typedef and only uses it in three places, changing that seems saner than
changing the field usages.

Back-patch because we're contemplating using the union of all branch
typedefs for future pgindent runs, so this won't fix anything if it
stays the same in back branches.
2015-05-24 13:03:45 -04:00
Bruce Momjian 807b9e0dff pgindent run for 9.5 2015-05-23 21:35:49 -04:00
Heikki Linnakangas 4fc72cc7bb Collection of typo fixes.
Use "a" and "an" correctly, mostly in comments. Two error messages were
also fixed (they were just elogs, so no translation work required). Two
function comments in pg_proc.h were also fixed. Etsuro Fujita reported one
of these, but I found a lot more with grep.

Also fix a few other typos spotted while grepping for the a/an typos.
For example, "consists out of ..." -> "consists of ...". Plus a "though"/
"through" mixup reported by Euler Taveira.

Many of these typos were in old code, which would be nice to backpatch to
make future backpatching easier. But much of the code was new, and I didn't
feel like crafting separate patches for each branch. So no backpatching.
2015-05-20 16:56:22 +03:00
Peter Eisentraut 0779f2ba2d Fix parse tree of DROP TRANSFORM and COMMENT ON TRANSFORM
The plain C string language name needs to be wrapped in makeString() so
that the parse tree is copyable.  This is detectable by
-DCOPY_PARSE_PLAN_TREES.  Add a test case for the COMMENT case.

Also make the quoting in the error messages more consistent.

discovered by Tom Lane
2015-05-18 22:55:14 -04:00
Andres Freund f3d3118532 Support GROUPING SETS, CUBE and ROLLUP.
This SQL standard functionality allows to aggregate data by different
GROUP BY clauses at once. Each grouping set returns rows with columns
grouped by in other sets set to NULL.

This could previously be achieved by doing each grouping as a separate
query, conjoined by UNION ALLs. Besides being considerably more concise,
grouping sets will in many cases be faster, requiring only one scan over
the underlying data.

The current implementation of grouping sets only supports using sorting
for input. Individual sets that share a sort order are computed in one
pass. If there are sets that don't share a sort order, additional sort &
aggregation steps are performed. These additional passes are sourced by
the previous sort step; thus avoiding repeated scans of the source data.

The code is structured in a way that adding support for purely using
hash aggregation or a mix of hashing and sorting is possible. Sorting
was chosen to be supported first, as it is the most generic method of
implementation.

Instead of, as in an earlier versions of the patch, representing the
chain of sort and aggregation steps as full blown planner and executor
nodes, all but the first sort are performed inside the aggregation node
itself. This avoids the need to do some unusual gymnastics to handle
having to return aggregated and non-aggregated tuples from underlying
nodes, as well as having to shut down underlying nodes early to limit
memory usage.  The optimizer still builds Sort/Agg node to describe each
phase, but they're not part of the plan tree, but instead additional
data for the aggregation node. They're a convenient and preexisting way
to describe aggregation and sorting.  The first (and possibly only) sort
step is still performed as a separate execution step. That retains
similarity with existing group by plans, makes rescans fairly simple,
avoids very deep plans (leading to slow explains) and easily allows to
avoid the sorting step if the underlying data is sorted by other means.

A somewhat ugly side of this patch is having to deal with a grammar
ambiguity between the new CUBE keyword and the cube extension/functions
named cube (and rollup). To avoid breaking existing deployments of the
cube extension it has not been renamed, neither has cube been made a
reserved keyword. Instead precedence hacking is used to make GROUP BY
cube(..) refer to the CUBE grouping sets feature, and not the function
cube(). To actually group by a function cube(), unlikely as that might
be, the function name has to be quoted.

Needs a catversion bump because stored rules may change.

Author: Andrew Gierth and Atri Sharma, with contributions from Andres Freund
Reviewed-By: Andres Freund, Noah Misch, Tom Lane, Svenne Krap, Tomas
    Vondra, Erik Rijkers, Marti Raudsepp, Pavel Stehule
Discussion: CAOeZVidmVRe2jU6aMk_5qkxnB7dfmPROzM7Ur8JPW5j8Y5X-Lw@mail.gmail.com
2015-05-16 03:46:31 +02:00
Simon Riggs 1e98fa0bf8 SQLStandard feature T613 Sampling now Supported 2015-05-15 15:51:31 -04:00
Simon Riggs f6d208d6e5 TABLESAMPLE, SQL Standard and extensible
Add a TABLESAMPLE clause to SELECT statements that allows
user to specify random BERNOULLI sampling or block level
SYSTEM sampling. Implementation allows for extensible
sampling functions to be written, using a standard API.
Basic version follows SQLStandard exactly. Usable
concrete use cases for the sampling API follow in later
commits.

Petr Jelinek

Reviewed by Michael Paquier and Simon Riggs
2015-05-15 14:37:10 -04:00
Fujii Masao ecd222e770 Support VERBOSE option in REINDEX command.
When this option is specified, a progress report is printed as each index
is reindexed.

Per discussion, we agreed on the following syntax for the extensibility of
the options.

    REINDEX (flexible options) { INDEX | ... } name

Sawada Masahiko.
Reviewed by Robert Haas, Fabrízio Mello, Alvaro Herrera, Kyotaro Horiguchi,
Jim Nasby and me.

Discussion: CAD21AoA0pK3YcOZAFzMae+2fcc3oGp5zoRggDyMNg5zoaWDhdQ@mail.gmail.com
2015-05-15 20:09:57 +09:00
Peter Eisentraut d02f16470f Replace some appendStringInfo* calls with more appropriate variants
Author: David Rowley <dgrowleyml@gmail.com>
2015-05-11 20:38:55 -04:00
Alvaro Herrera b488c580ae Allow on-the-fly capture of DDL event details
This feature lets user code inspect and take action on DDL events.
Whenever a ddl_command_end event trigger is installed, DDL actions
executed are saved to a list which can be inspected during execution of
a function attached to ddl_command_end.

The set-returning function pg_event_trigger_ddl_commands can be used to
list actions so captured; it returns data about the type of command
executed, as well as the affected object.  This is sufficient for many
uses of this feature.  For the cases where it is not, we also provide a
"command" column of a new pseudo-type pg_ddl_command, which is a
pointer to a C structure that can be accessed by C code.  The struct
contains all the info necessary to completely inspect and even
reconstruct the executed command.

There is no actual deparse code here; that's expected to come later.
What we have is enough infrastructure that the deparsing can be done in
an external extension.  The intention is that we will add some deparsing
code in a later release, as an in-core extension.

A new test module is included.  It's probably insufficient as is, but it
should be sufficient as a starting point for a more complete and
future-proof approach.

Authors: Álvaro Herrera, with some help from Andres Freund, Ian Barwick,
Abhijit Menon-Sen.

Reviews by Andres Freund, Robert Haas, Amit Kapila, Michael Paquier,
Craig Ringer, David Steele.
Additional input from Chris Browne, Dimitri Fontaine, Stephen Frost,
Petr Jelínek, Tom Lane, Jim Nasby, Steven Singer, Pavel Stěhule.

Based on original work by Dimitri Fontaine, though I didn't use his
code.

Discussion:
  https://www.postgresql.org/message-id/m2txrsdzxa.fsf@2ndQuadrant.fr
  https://www.postgresql.org/message-id/20131108153322.GU5809@eldon.alvh.no-ip.org
  https://www.postgresql.org/message-id/20150215044814.GL3391@alvh.no-ip.org
2015-05-11 19:14:31 -03:00
Andrew Dunstan cb9fa802b3 Add new OID alias type regnamespace
Catalog version bumped

Kyotaro HORIGUCHI
2015-05-09 13:36:52 -04:00
Andrew Dunstan 0c90f6769d Add new OID alias type regrole
The new type has the scope of whole the database cluster so it doesn't
behave the same as the existing OID alias types which have database
scope,
concerning object dependency. To avoid confusion constants of the new
type are prohibited from appearing where dependencies are made involving
it.

Also, add a note to the docs about possible MVCC violation and
optimization issues, which are general over the all reg* types.

Kyotaro Horiguchi
2015-05-09 13:06:49 -04:00
Stephen Frost a97e0c3354 Add pg_file_settings view and function
The function and view added here provide a way to look at all settings
in postgresql.conf, any #include'd files, and postgresql.auto.conf
(which is what backs the ALTER SYSTEM command).

The information returned includes the configuration file name, line
number in that file, sequence number indicating when the parameter is
loaded (useful to see if it is later masked by another definition of the
same parameter), parameter name, and what it is set to at that point.
This information is updated on reload of the server.

This is unfiltered, privileged, information and therefore access is
restricted to superusers through the GRANT system.

Author: Sawada Masahiko, various improvements by me.
Reviewers: David Steele
2015-05-08 19:09:26 -04:00
Andres Freund 168d5805e4 Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.
The newly added ON CONFLICT clause allows to specify an alternative to
raising a unique or exclusion constraint violation error when inserting.
ON CONFLICT refers to constraints that can either be specified using a
inference clause (by specifying the columns of a unique constraint) or
by naming a unique or exclusion constraint.  DO NOTHING avoids the
constraint violation, without touching the pre-existing row.  DO UPDATE
SET ... [WHERE ...] updates the pre-existing tuple, and has access to
both the tuple proposed for insertion and the existing tuple; the
optional WHERE clause can be used to prevent an update from being
executed.  The UPDATE SET and WHERE clauses have access to the tuple
proposed for insertion using the "magic" EXCLUDED alias, and to the
pre-existing tuple using the table name or its alias.

This feature is often referred to as upsert.

This is implemented using a new infrastructure called "speculative
insertion". It is an optimistic variant of regular insertion that first
does a pre-check for existing tuples and then attempts an insert.  If a
violating tuple was inserted concurrently, the speculatively inserted
tuple is deleted and a new attempt is made.  If the pre-check finds a
matching tuple the alternative DO NOTHING or DO UPDATE action is taken.
If the insertion succeeds without detecting a conflict, the tuple is
deemed inserted.

To handle the possible ambiguity between the excluded alias and a table
named excluded, and for convenience with long relation names, INSERT
INTO now can alias its target table.

Bumps catversion as stored rules change.

Author: Peter Geoghegan, with significant contributions from Heikki
    Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes.
Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs,
    Dean Rasheed, Stephen Frost and many others.
2015-05-08 05:43:10 +02:00
Robert Haas 924bcf4f16 Create an infrastructure for parallel computation in PostgreSQL.
This does four basic things.  First, it provides convenience routines
to coordinate the startup and shutdown of parallel workers.  Second,
it synchronizes various pieces of state (e.g. GUCs, combo CID
mappings, transaction snapshot) from the parallel group leader to the
worker processes.  Third, it prohibits various operations that would
result in unsafe changes to that state while parallelism is active.
Finally, it propagates events that would result in an ErrorResponse,
NoticeResponse, or NotifyResponse message being sent to the client
from the parallel workers back to the master, from which they can then
be sent on to the client.

Robert Haas, Amit Kapila, Noah Misch, Rushabh Lathia, Jeevan Chalke.
Suggestions and review from Andres Freund, Heikki Linnakangas, Noah
Misch, Simon Riggs, Euler Taveira, and Jim Nasby.
2015-04-30 15:02:14 -04:00
Andres Freund 5aa2350426 Introduce replication progress tracking infrastructure.
When implementing a replication solution ontop of logical decoding, two
related problems exist:
* How to safely keep track of replication progress
* How to change replication behavior, based on the origin of a row;
  e.g. to avoid loops in bi-directional replication setups

The solution to these problems, as implemented here, consist out of
three parts:

1) 'replication origins', which identify nodes in a replication setup.
2) 'replication progress tracking', which remembers, for each
   replication origin, how far replay has progressed in a efficient and
   crash safe manner.
3) The ability to filter out changes performed on the behest of a
   replication origin during logical decoding; this allows complex
   replication topologies. E.g. by filtering all replayed changes out.

Most of this could also be implemented in "userspace", e.g. by inserting
additional rows contain origin information, but that ends up being much
less efficient and more complicated.  We don't want to require various
replication solutions to reimplement logic for this independently. The
infrastructure is intended to be generic enough to be reusable.

This infrastructure also replaces the 'nodeid' infrastructure of commit
timestamps. It is intended to provide all the former capabilities,
except that there's only 2^16 different origins; but now they integrate
with logical decoding. Additionally more functionality is accessible via
SQL.  Since the commit timestamp infrastructure has also been introduced
in 9.5 (commit 73c986add) changing the API is not a problem.

For now the number of origins for which the replication progress can be
tracked simultaneously is determined by the max_replication_slots
GUC. That GUC is not a perfect match to configure this, but there
doesn't seem to be sufficient reason to introduce a separate new one.

Bumps both catversion and wal page magic.

Author: Andres Freund, with contributions from Petr Jelinek and Craig Ringer
Reviewed-By: Heikki Linnakangas, Petr Jelinek, Robert Haas, Steve Singer
Discussion: 20150216002155.GI15326@awork2.anarazel.de,
    20140923182422.GA15776@alap3.anarazel.de,
    20131114172632.GE7522@alap2.anarazel.de
2015-04-29 19:30:53 +02:00
Andres Freund 6aab1f45ac Fix various typos and grammar errors in comments.
Author: Dmitriy Olshevskiy
Discussion: 553D00A6.4090205@bk.ru
2015-04-26 18:42:31 +02:00
Peter Eisentraut cac7658205 Add transforms feature
This provides a mechanism for specifying conversions between SQL data
types and procedural languages.  As examples, there are transforms
for hstore and ltree for PL/Perl and PL/Python.

reviews by Pavel Stěhule and Andres Freund
2015-04-26 10:33:14 -04:00
Andres Freund cef939c347 Rename pg_replication_slot's new active_in to active_pid.
In d811c037ce active_in was added but discussion since showed that
active_pid is preferred as a name.

Discussion: CAMsr+YFKgZca5_7_ouaMWxA5PneJC9LNViPzpDHusaPhU9pA7g@mail.gmail.com
2015-04-22 09:43:40 +02:00
Andres Freund d811c037ce Add 'active_in' column to pg_replication_slots.
Right now it is visible whether a replication slot is active in any
session, but not in which.  Adding the active_in column, containing the
pid of the backend having acquired the slot, makes it much easier to
associate pg_replication_slots entries with the corresponding
pg_stat_replication/pg_stat_activity row.

This should have been done from the start, but I (Andres) dropped the
ball there somehow.

Author: Craig Ringer, revised by me Discussion:
CAMsr+YFKgZca5_7_ouaMWxA5PneJC9LNViPzpDHusaPhU9pA7g@mail.gmail.com
2015-04-21 11:51:06 +02:00
Peter Eisentraut 30982be4e5 Integrate pg_upgrade_support module into backend
Previously, these functions were created in a schema "binary_upgrade",
which was deleted after pg_upgrade was finished.  Because we don't want
to keep that schema around permanently, move them to pg_catalog but
rename them with a binary_upgrade_... prefix.

The provided functions are only small wrappers around global variables
that were added specifically for pg_upgrade use, so keeping the module
separate does not create any modularity.

The functions still check that they are only called in binary upgrade
mode, so it is not possible to call these during normal operation.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2015-04-14 19:26:37 -04:00
Magnus Hagander 9029f4b374 Add system view pg_stat_ssl
This view shows information about all connections, such as if the
connection is using SSL, which cipher is used, and which client
certificate (if any) is used.

Reviews by Alex Shulgin, Heikki Linnakangas, Andres Freund & Michael Paquier
2015-04-12 19:07:46 +02:00
Andres Freund 06d36fa40c Fix typo in eb68379c3.
I'd accidentally missed to rename PG_FORCE_NULL to BKI_FORCE_NULL in one
place.

Author: Jeevan Chalke
Discussion: CAM2+6=VPoow5PqgqiTjPX4QNeokb7op8aD_8Zg3QnHZMvvU0GQ@mail.gmail.com
2015-04-09 13:29:22 +02:00
Fujii Masao 026fafde91 Fix typo in comment. 2015-04-08 20:55:43 +09:00
Alvaro Herrera e9a077cad3 pg_event_trigger_dropped_objects: add is_temp column
It now also reports temporary objects dropped that are local to the
backend.  Previously we weren't reporting any temp objects because it
was deemed unnecessary; but as it turns out, it is necessary if we want
to keep close track of DDL command execution inside one session.  Temp
objects are reported as living in schema pg_temp, which works because
such a schema-qualification always refers to the temp objects of the
current session.
2015-04-06 11:40:55 -03:00
Alvaro Herrera 70dc2db7f1 Fix object identities for pg_conversion objects
This was already fixed in 0d906798f, but I failed to update the
array-formatted case.  This is not backpatched, since this only affects
the code path introduced by commit a676201490.
2015-04-06 11:15:13 -03:00