Commit Graph

115 Commits

Author SHA1 Message Date
Tom Lane 216f9c1ab3 Fix tupdesc lifespan bug with AfterTriggersTableData.storeslot.
Commit 25936fd46 adjusted things so that the "storeslot" we use
for remapping trigger tuples would have adequate lifespan, but it
neglected to consider the lifespan of the tuple descriptor that
the slot depends on.  It turns out that in at least some cases, the
tupdesc we are passing is a refcounted tupdesc, and the refcount for
the slot's reference can get assigned to a resource owner having
different lifespan than the slot does.  That leads to an error like
"tupdesc reference 0x7fdef236a1b8 is not owned by resource owner
SubTransaction".  Worse, because of a second oversight in the same
commit, we'd try to free the same tupdesc refcount again while
cleaning up after that error, leading to recursive errors and an
"ERRORDATA_STACK_SIZE exceeded" PANIC.

To fix the initial problem, let's just make a non-refcounted copy
of the tupdesc we're supposed to use.  That seems likely to guard
against additional problems, since there's no strong reason for
this code to assume that what it's given is a refcounted tupdesc;
in which case there's an independent hazard of the tupdesc having
shorter lifespan than the slot does.  (I didn't bother trying to
free said copy, since it should go away anyway when the (sub)
transaction context is cleaned up.)

The other issue can be fixed by making the code added to
AfterTriggerFreeQuery work like the rest of that function, ie be
sure that it doesn't try to free the same slot twice in the event
of recursive error cleanup.

While here, also clean up minor stylistic issues in the test case
added by 25936fd46: don't use "create or replace function", as any
name collision within the tests is likely to have ill effects
that that won't mask; and don't use function names as generic as
trigger_function1, especially if you're not going to drop them
at the end of the test stanza.

Per bug #17607 from Thomas Mc Kay.  Back-patch to v12, as the
previous fix was.

Discussion: https://postgr.es/m/17607-bd8ccc81226f7f80@postgresql.org
2022-09-25 17:10:58 -04:00
Peter Eisentraut 26f7802beb Message style improvements 2022-09-24 18:41:25 -04:00
Alvaro Herrera 90a4b64134
regress: fix test instability
Having additional triggers in a test table made the ORDER BY clauses in
old queries underspecified.  Add another column there for stability.

Per sporadic buildfarm pink.
2022-08-05 11:55:52 +02:00
Alvaro Herrera ec0925c22a
Fix ENABLE/DISABLE TRIGGER to handle recursion correctly
Using ATSimpleRecursion() in ATPrepCmd() to do so as bbb927b4db did is
not correct, because ATPrepCmd() can't distinguish between triggers that
may be cloned and those that may not, so would wrongly try to recurse
for the latter category of triggers.

So this commit restores the code in EnableDisableTrigger() that
86f575948c had added to do the recursion, which would do it only for
triggers that may be cloned, that is, row-level triggers.  This also
changes tablecmds.c such that ATExecCmd() is able to pass the value of
ONLY flag down to EnableDisableTrigger() using its new 'recurse'
parameter.

This also fixes what seems like an oversight of 86f575948c that the
recursion to partition triggers would only occur if EnableDisableTrigger()
had actually changed the trigger.  It is more apt to recurse to inspect
partition triggers even if the parent's trigger didn't need to be
changed: only then can we be certain that all descendants share the same
state afterwards.

Backpatch all the way back to 11, like bbb927b4db.  Care is taken not
to break ABI compatibility (and that no catversion bump is needed.)

Co-authored-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Dmitry Koval <d.koval@postgrespro.ru>
Discussion: https://postgr.es/m/CA+HiwqG-cZT3XzGAnEgZQLoQbyfJApVwOTQaCaas1mhpf+4V5A@mail.gmail.com
2022-08-05 09:47:26 +02:00
Michael Paquier 12c254c99f Tweak detail and hint messages to be consistent with project policy
Detail and hint messages should be full sentences and should end with a
period, but some of the messages newly-introduced in v15 did not follow
that.

Author: Justin Pryzby
Reviewed-by: Álvaro Herrera
Discussion: https://postgr.es/m/20220719120948.GF12702@telsasoft.com
Backpatch-through: 15
2022-07-20 09:50:12 +09:00
Alvaro Herrera 7103ebb7aa
Add support for MERGE SQL command
MERGE performs actions that modify rows in the target table using a
source table or query. MERGE provides a single SQL statement that can
conditionally INSERT/UPDATE/DELETE rows -- a task that would otherwise
require multiple PL statements.  For example,

MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
  UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
  DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
  INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
  DO NOTHING;

MERGE works with regular tables, partitioned tables and inheritance
hierarchies, including column and row security enforcement, as well as
support for row and statement triggers and transition tables therein.

MERGE is optimized for OLTP and is parameterizable, though also useful
for large scale ETL/ELT. MERGE is not intended to be used in preference
to existing single SQL commands for INSERT, UPDATE or DELETE since there
is some overhead.  MERGE can be used from PL/pgSQL.

MERGE does not support targetting updatable views or foreign tables, and
RETURNING clauses are not allowed either.  These limitations are likely
fixable with sufficient effort.  Rewrite rules are also not supported,
but it's not clear that we'd want to support them.

Author: Pavan Deolasee <pavan.deolasee@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Reviewed-by: Peter Geoghegan <pg@bowt.ie> (earlier versions)
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Japin Li <japinli@hotmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
Discussion: https://postgr.es/m/20201231134736.GA25392@alvherre.pgsql
2022-03-28 16:47:48 +02:00
Tom Lane cc50080a82 Rearrange core regression tests to reduce cross-script dependencies.
The idea behind this patch is to make it possible to run individual
test scripts without running the entire core test suite.  Making all
the scripts completely independent would involve a massive rewrite,
and would probably be worse for coverage of things like concurrent DDL.
So this patch just does what seems practical with limited changes.

The net effect is that any test script can be run after running
limited earlier dependencies:
* all scripts depend on test_setup
* many scripts depend on create_index
* other dependencies are few in number, and are documented in
  the parallel_schedule file.

To accomplish this, I chose a small number of commonly-used tables
and moved their creation and filling into test_setup.  Later scripts
are expected not to modify these tables' data contents, for fear of
affecting other scripts' results.  Also, our former habit of declaring
all C functions in one place is now gone in favor of declaring them
where they're used, if that's just one script, or in test_setup if
necessary.

There's more that could be done to remove some of the remaining
inter-script dependencies, but significantly more-invasive changes
would be needed, and at least for now it doesn't seem worth it.

Discussion: https://postgr.es/m/1114748.1640383217@sss.pgh.pa.us
2022-02-08 15:30:38 -05:00
Tom Lane 9007d4ea77 Fix psql \d's query for identifying parent triggers.
The original coding (from c33869cc3) failed with "more than one row
returned by a subquery used as an expression" if there were unrelated
triggers of the same tgname on parent partitioned tables.  (That's
possible because statement-level triggers don't get inherited.)  Fix
by applying LIMIT 1 after sorting the candidates by inheritance level.

Also, wrap the subquery in a CASE so that we don't have to execute it at
all when the trigger is visibly non-inherited.  Aside from saving some
cycles, this avoids the need for a confusing and undocumented NULLIF().

While here, tweak the format of the emitted query to look a bit
nicer for "psql -E", and add some explanation of this subquery,
because it badly needs it.

Report and patch by Justin Pryzby (with some editing by me).
Back-patch to v13 where the faulty code came in.

Discussion: https://postgr.es/m/20211217154356.GJ17618@telsasoft.com
2022-01-17 21:19:02 -05:00
Alvaro Herrera f4566345cf
Create foreign key triggers in partitioned tables too
While user-defined triggers defined on a partitioned table have
a catalog definition for both it and its partitions, internal
triggers used by foreign keys defined on partitioned tables only
have a catalog definition for its partitions.  This commit fixes
that so that partitioned tables get the foreign key triggers too,
just like user-defined triggers.  Moreover, like user-defined
triggers, partitions' internal triggers will now also have their
tgparentid set appropriately.  This is to allow subsequent commit(s)
to make the foreign key related events to be fired in some cases
using the parent table triggers instead of those of partitions'.

This also changes what tgisinternal means in some cases.  Currently,
it means either that the trigger is an internal implementation object
of a foreign key constraint, or a "child" trigger on a partition
cloned from the trigger on the parent.  This commit changes it to
only mean the former to avoid confusion.  As for the latter, it can
be told by tgparentid being nonzero, which is now true both for user-
defined and foreign key's internal triggers.

Author: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Arne Roland <A.Roland@index.de>
Discussion: https://postgr.es/m/CA+HiwqG7LQSK+n8Bki8tWv7piHD=PnZro2y6ysU2-28JS6cfgQ@mail.gmail.com
2022-01-05 19:00:13 -03:00
Alvaro Herrera 6beb38cfc9
Make new test immune to collation
Animals running in Czech locale failed.  I could try to find table names
that don't have this problem, but it seems simpler to just use the C
locale.

Per buildfarm
2021-07-23 11:52:48 -04:00
Alvaro Herrera 80ba4bb383
Make ALTER TRIGGER RENAME consistent for partitioned tables
Renaming triggers on partitioned tables had two problems: first,
it did not recurse to renaming the triggers on the partitions; and
second, it failed to prohibit renaming clone triggers.  Having triggers
with different names in partitions is pointless, and furthermore pg_dump
would not preserve names for partitions anyway.

Not backpatched -- making the ALTER TRIGGER throw an error in stable
versions might cause problems for existing scripts.

Co-authored-by: Arne Roland <A.Roland@index.de>
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/d0fd7040c2fb4de1a111b9d9ccc456b8@index.de
2021-07-22 18:33:47 -04:00
Alvaro Herrera f0e21f2f61
Fix pg_dump for disabled triggers on partitioned tables
pg_dump failed to preserve the 'enabled' flag (which can be not only
disabled, but also REPLICA or ALWAYS) for partitions which had it
changed from their respective parents.  Attempt to handle that by
including a definition for such triggers in the dump, but replace the
standard CREATE TRIGGER line with an ALTER TRIGGER line.

Backpatch to 11, where these triggers can exist.  In branches 11 and 12,
pick up a few test lines from commit b9b408c487 to verify that
pg_upgrade is okay with these arrangements.

Co-authored-by: Justin Pryzby <pryzby@telsasoft.com>
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20200930223450.GA14848@telsasoft.com
2021-07-16 17:29:22 -04:00
Alvaro Herrera df80fa2ee5
Preserve firing-on state when cloning row triggers to partitions
When triggers are cloned from partitioned tables to their partitions,
the 'tgenabled' flag (origin/replica/always/disable) was not propagated.
Make it so that the flag on the trigger on partition is initially set to
the same value as on the partitioned table.

Add a test case to verify the behavior.

Backpatch to 11, where this appeared in commit 86f575948c.

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20200930223450.GA14848@telsasoft.com
2021-07-16 13:01:43 -04:00
Alvaro Herrera 25936fd46c
Fix use-after-free bug with AfterTriggersTableData.storeslot
AfterTriggerSaveEvent() wrongly allocates the slot in execution-span
memory context, whereas the correct thing is to allocate it in
a transaction-span context, because that's where the enclosing
AfterTriggersTableData instance belongs into.

Backpatch to 12 (the test back to 11, where it works well with no code
changes, and it's good to have to confirm that the case was previously
well supported); this bug seems introduced by commit ff11e7f4b9.

Reported-by: Bertrand Drouvot <bdrouvot@amazon.com>
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/39a71864-b120-5a5c-8cc5-c632b6f16761@amazon.com
2021-02-27 18:09:15 -03:00
Alvaro Herrera 6f5c8a8ec2
Remove bogus restriction from BEFORE UPDATE triggers
In trying to protect the user from inconsistent behavior, commit
487e9861d0 "Enable BEFORE row-level triggers for partitioned tables"
tried to prevent BEFORE UPDATE FOR EACH ROW triggers from moving the row
from one partition to another.  However, it turns out that the
restriction is wrong in two ways: first, it fails spuriously, preventing
valid situations from working, as in bug #16794; and second, they don't
protect from any misbehavior, because tuple routing would cope anyway.

Fix by removing that restriction.

We keep the same restriction on BEFORE INSERT FOR EACH ROW triggers,
though.  It is valid and useful there.  In the future we could remove it
by having tuple reroute work for inserts as it does for updates.

Backpatch to 13.

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Phillip Menke <pg@pmenke.de>
Discussion: https://postgr.es/m/16794-350a655580fbb9ae@postgresql.org
2021-01-28 16:56:07 -03:00
Heikki Linnakangas 68b1a4877e Fix a few comments that referred to copy.c.
Missed these in the previous commit.
2020-11-23 11:36:13 +02:00
Tom Lane 92bf7e2d02 Provide the OR REPLACE option for CREATE TRIGGER.
This is mostly straightforward.  However, we disallow replacing
constraint triggers or changing the is-constraint property; perhaps
that can be added later, but the complexity versus benefit tradeoff
doesn't look very good.

Also, no special thought is taken here for whether replacing an
existing trigger should result in changes to queued-but-not-fired
trigger actions.  We just document that if you're surprised by the
results, too bad, don't do that.  (Note that any such pending trigger
activity would have to be within the current session.)

Takamichi Osumi, reviewed at various times by Surafel Temesgen,
Peter Smith, and myself

Discussion: https://postgr.es/m/0DDF369B45A1B44B8A687ED43F06557C010BC362@G01JPEXMBYT03
2020-11-14 17:05:34 -05:00
Tom Lane 8b39345a9d In INSERT/UPDATE, use the table's real tuple descriptor as target.
This back-patches commit 20d3fe900 into the v12 and v13 branches.
At the time I thought that commit was not fixing any observable
bug, but Bertrand Drouvot showed otherwise: adding a dropped column
to the previously-considered scenario crashes v12 and v13, unless the
dropped column happens to be an integer.  That is, of course, because
the tupdesc we derive from the plan output tlist fails to describe
the dropped column accurately, so that we'll do the wrong thing with
a tuple in which that column isn't NULL.

There is no bug in pre-v12 branches because they already did use
the table's real tuple descriptor for any trigger-returned tuple.
It seems that this set of bugs can be blamed on the changes that
removed es_trig_tuple_slot, though I've not attempted to pin that
down precisely.

Although there's no code change needed in HEAD, update the test case
to include a dropped column there too.

Discussion: https://postgr.es/m/db5d97c8-f48a-51e2-7b08-b73d5434d425@amazon.com
Discussion: https://postgr.es/m/16644-5da7ef98a7ac4545@postgresql.org
2020-11-08 13:08:36 -05:00
Magnus Hagander 44a184cb68 Use the non-deprecated TG_TABLE_MAME in test trigger
Commit 3a9ae3d206 (back in 2006) deprecated TG_RELNAME
in favor of TG_TABLE_NAME, but the existing usage in test
cases has remained till today. Change to use TG_TABLE_NAME
instead (TG_RELNAME is still covered by a test case).
2020-11-03 10:19:55 +01:00
Tom Lane ba9f18abd3 Fix corner case for a BEFORE ROW UPDATE trigger returning OLD.
If the old row has any "missing" attributes that are supposed to
be retrieved from an associated tuple descriptor, the wrong things
happened because the trigger result is shoved directly into an
executor slot that lacks the missing-attribute data.  Notably,
CHECK-constraint verification would incorrectly see those columns
as NULL, and so would RETURNING-list evaluation.

Band-aid around this by forcibly expanding the tuple before passing
it to the trigger function.  (IMO it was a fundamental misdesign to
put the missing-attribute data into tuple constraints, which so
much of the system considers to be optional.  But we're probably
stuck with that now, and will have to continue to apply band-aids
as we find other places with similar issues.)

Back-patch to v12.  v11 would also have the issue, except that
commit 920311ab1 already applied a similar band-aid.  That forced
expansion in more cases than seem really necessary, though, so
this isn't a directly equivalent fix.

Amit Langote, with some cosmetic changes by me

Discussion: https://postgr.es/m/16644-5da7ef98a7ac4545@postgresql.org
2020-10-25 13:57:46 -04:00
Alvaro Herrera bbb927b4db
Fix ALTER TABLE .. ENABLE/DISABLE TRIGGER recursion
More precisely, correctly handle the ONLY flag indicating not to
recurse.  This was implemented in 86f575948c by recursing in
trigger.c, but that's the wrong place; use ATSimpleRecursion instead,
which behaves properly.  However, because legacy inheritance has never
recursed in that situation, make sure to do that only for new-style
partitioning.

I noticed this problem while testing a fix for another bug in the
vicinity.

This has been wrong all along, so backpatch to 11.

Discussion: https://postgr.es/m/20201016235925.GA29829@alvherre.pgsql
2020-10-20 19:22:09 -03:00
Alvaro Herrera c33869cc3b
psql \d: Display table where trigger is defined, if inherited
It's important to know that a trigger is cloned from a parent table,
because of the behavior that the trigger is dropped on detach.  Make
psql's \d display it.

We'd like to backpatch, but lack of the pg_trigger.tgparentid column
makes it more difficult.  Punt for now.  If somebody wants to volunteer
an implementation that reads pg_depend on older versions, that can
probably be backpatched.

Authors: Justin Pryzby, Amit Langote, Álvaro Herrera
Discussion: https://postgr.es/m/20200419002206.GM26953@telsasoft.com
2020-04-21 18:37:26 -04:00
Alvaro Herrera afccd76f1c
Fix detaching partitions with cloned row triggers
When a partition is detached, any triggers that had been cloned from its
parent were not properly disentangled from its parent triggers.
This resulted in triggers that could not be dropped because they
depended on the trigger in the trigger in the no-longer-parent table:
  ALTER TABLE t DETACH PARTITION t1;
  DROP TRIGGER trig ON t1;
    ERROR:  cannot drop trigger trig on table t1 because trigger trig on table t requires it
    HINT:  You can drop trigger trig on table t instead.

Moreover the table can no longer be re-attached to its parent, because
the trigger name is already taken:
  ALTER TABLE t ATTACH PARTITION t1 FOR VALUES FROM (1)TO(2);
    ERROR:  trigger "trig" for relation "t1" already exists

The former is a bug introduced in commit 86f575948c.  (The latter is
not necessarily a bug, but it makes the bug more uncomfortable.)

To avoid the complexity that would be needed to tell whether the trigger
has a local definition that has to be merged with the one coming from
the parent table, establish the behavior that the trigger is removed
when the table is detached.

Backpatch to pg11.

Author: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/20200408152412.GZ2228@telsasoft.com
2020-04-21 13:57:00 -04:00
Alvaro Herrera 487e9861d0
Enable BEFORE row-level triggers for partitioned tables
... with the limitation that the tuple must remain in the same
partition.

Reviewed-by: Ashutosh Bapat
Discussion: https://postgr.es/m/20200227165158.GA2071@alvherre.pgsql
2020-03-18 18:58:05 -03:00
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
Alvaro Herrera 1fa846f1c9 Fix cloning of row triggers to sub-partitions
When row triggers exist in partitioned partitions that are not either
part of FKs or deferred unique constraints, they are not correctly
cloned to their partitions.  That's because they are marked "internal",
and those are purposefully skipped when doing the clone triggers dance.
Fix by relaxing the condition on which internal triggers are skipped.

Amit Langote initially diagnosed the problem and proposed a fix, but I
used a different approach.

Reported-by: Petr Fedorov
Discussion: https://postgr.es/m/6b3f0646-ba8c-b3a9-c62d-1c6651a1920f@phystech.edu
2020-01-02 17:04:24 -03:00
Tom Lane 1ced082b95 Prevent possible double-free when update trigger returns old tuple.
This is a variant of the problem fixed in commit 25b692568, which
unfortunately we failed to detect at the time.  If an update trigger
returns the "old" tuple, as it's entitled to do, then a subsequent
iteration of the loop in ExecBRUpdateTriggers would have "oldtuple"
equal to "trigtuple" and would fail to notice that it shouldn't
free that.

In addition to fixing the code, extend the test case added by
25b692568 so that it covers multiple-trigger-iterations cases.

This problem does not manifest in v12/HEAD, as a result of the
relevant code having been largely rewritten for slotification.
However, include the test case into v12/HEAD anyway, since this
is clearly an area that someone could break again in future.

Per report from Piotr Gabriel Kosinski.  Back-patch into all
supported branches, since the bug seems quite old.

Diagnosis and code fix by Thomas Munro, test case by me.

Discussion: https://postgr.es/m/CAFMLSdP0rd7LqC3j-H6Fh51FYSt5A10DDh-3=W4PPc4LLUQ8YQ@mail.gmail.com
2019-08-15 20:04:19 -04:00
Alvaro Herrera 2c84ea6cf9 Propagate trigger arguments to partitions
We were creating the cloned triggers with an empty list of arguments,
losing the ones that had been specified by the user when creating the
trigger in the partitioned table.  Repair.

This was forgotten in commit 86f575948c.

Author: Patrick McHardy
Reviewed-by: Tomas Vondra
Discussion: https://postgr.es/m/20190709130027.amr2cavjvo7rdvac@access1.trash.net
Discussion: https://postgr.es/m/15752-123bc90287986de4@postgresql.org
2019-07-09 17:16:36 -04:00
Andres Freund 41f5e04aec Fix a number of issues around modifying a previously updated row.
This commit fixes three, unfortunately related, issues:

1) Since 5db6df0c01, the introduction of DML via tableam, it was
   possible to trigger "ERROR: unexpected table_lock_tuple status: 1"
   when updating a row that was previously updated in the same
   transaction - but only when the previously updated row was before
   updated in a concurrent transaction (and READ COMMITTED was
   used). The reason for that was that that case simply wasn't
   expected. Fixing that lead to:

2) Even before the above commit, there were error checks (introduced
   in 6868ed7491) preventing a row being updated by different
   commands within the same statement (say in a function called by an
   UPDATE) - but that check wasn't performed when the row was first
   updated in a concurrent transaction - instead the second update was
   silently skipped in that case. After this change we throw the same
   error as we'd without the concurrent transaction.

3) The error messages (introduced in 6868ed7491) preventing such
   updates emitted the same error message for both DELETE and
   UPDATE ("tuple to be updated was already modified by an operation
   triggered by the current command"). While that could be changed
   separately, it made it hard to write tests that verify the correct
   correct behavior of the code.

This commit changes heap's implementation of table_lock_tuple() to
return TM_SelfModified instead of TM_Invisible (previously loosely
modeled after EvalPlanQualFetch), and teaches nodeModifyTable.c to
handle that in response to table_lock_tuple() and not just in response
to table_(delete|update).

Additionally it fixes the wrong error message (see 3 above). The
comment for table_lock_tuple() is also adjusted to state that
TM_Deleted won't return information in TM_FailureData - it'll not
always be available.

This also adds tests to ensure that DELETE/UPDATE correctly error out
when affecting a row that concurrently was modified by another
transaction.

Author: Andres Freund
Reported-By: Tom Lane, when investigating a bug bug fix to another bug
    by Amit Langote
Discussion: https://postgr.es/m/19321.1554567786@sss.pgh.pa.us
2019-04-07 22:14:47 -07:00
Tom Lane ab5fcf2b04 Fix plan created for inherited UPDATE/DELETE with all tables excluded.
In the case where inheritance_planner() finds that every table has
been excluded by constraints, it thought it could get away with
making a plan consisting of just a dummy Result node.  While certainly
there's no updating or deleting to be done, this had two user-visible
problems: the plan did not report the correct set of output columns
when a RETURNING clause was present, and if there were any
statement-level triggers that should be fired, it didn't fire them.

Hence, rather than only generating the dummy Result, we need to
stick a valid ModifyTable node on top, which requires a tad more
effort here.

It's been broken this way for as long as inheritance_planner() has
known about deleting excluded subplans at all (cf commit 635d42e9c),
so back-patch to all supported branches.

Amit Langote and Tom Lane, per a report from Petr Fedorov.

Discussion: https://postgr.es/m/5da6f0f0-1364-1876-6978-907678f89a3e@phystech.edu
2019-02-22 12:23:19 -05:00
Peter Eisentraut 0c1f8f166c Use EXECUTE FUNCTION syntax for triggers more
Change pg_dump and ruleutils.c to use the FUNCTION keyword instead of
PROCEDURE in trigger and event trigger definitions.

This completes the pieces of the transition started in
0a63f996e0 that were kept out of
PostgreSQL 11 because of the required catversion change.

Discussion: https://www.postgresql.org/message-id/381bef53-f7be-29c8-d977-948e389161d6@2ndquadrant.com
2019-02-07 09:21:34 +01:00
Andres Freund 8cc157b234 Fix ALTER TRIGGER ... RENAME, broken in WITH OIDS removal.
I (Andres) broke this in 578b229718.

Author: Rushabh Lathia
Discussion: https://postgr.es/m/CAGPqQf04PywZX3sVQaF6H=oLiW9GJncRW+=e78vTy4MokEWcZw@mail.gmail.com
2019-01-21 09:13:43 -08:00
Michael Paquier 730422afcd Fix some errhint and errdetail strings missing a period
As per the error message style guide of the documentation, those should
be full sentences.

Author: Daniel Gustafsson
Reviewed-by: Michael Paquier, Álvaro Herrera
Discussion: https://1E8D49B4-16BC-4420-B4ED-58501D9E076B@yesql.se
2018-12-07 07:47:42 +09:00
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 0a63f996e0 Change PROCEDURE to FUNCTION in CREATE TRIGGER syntax
Since procedures are now a different thing from functions, change the
CREATE TRIGGER and CREATE EVENT TRIGGER syntax to use FUNCTION in the
clause that specifies the function.  PROCEDURE is still accepted for
compatibility.

pg_dump and ruleutils.c output is not changed yet, because that would
require a change in information_schema.sql and thus a catversion change.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:44:49 +02:00
Heikki Linnakangas 17b715c634 Add test case for EEOP_INNER_SYSVAR/EEOP_OUTER_SYSVAR executor opcodes.
The EEOP_INNER_SYSVAR and EEOP_OUTER_SYSVAR executor opcodes are not
exercised by normal queries, because setrefs.c will resolve the references
to system columns in the scan nodes already. Join nodes refer to them by
their position in the child node's target list, like user columns.

The only place where those opcodes are used, is in evaluating a trigger's
WHEN condition that references system columns. Trigger evaluation abuses
the INNER/OUTER Vars to refer to the OLD and NEW tuples. The code to handle
the opcodes is pretty straightforward, but it seems like a good idea to
have some test coverage for them, anyway, so that they don't get removed or
broken by accident.

Author: Ashutosh Bapat, with some changes by me.
Discussion: https://www.postgresql.org/message-id/CAFjFpRerUFX=T0nSnCoroXAJMoo-xah9J+pi7+xDUx86PtQmew@mail.gmail.com
2018-07-10 16:16:14 +03:00
Tom Lane b86b7bfa3e Improve English wording of some other getObjectDescription() messages.
Print columns as "column C of <relation>" rather than "<relation> column
C".  This seems to read noticeably better in English, as evidenced by the
regression test output changes, and the code change also makes it possible
for translators to adjust the phrase order in other languages.

Also change the output for OCLASS_DEFAULT from "default for %s" to
"default value for %s".  This seems to read better and is also more
consistent with the output of, for instance, getObjectTypeDescription().

Kyotaro Horiguchi, per a complaint from me

Discussion: https://postgr.es/m/20180522.182020.114074746.horiguchi.kyotaro@lab.ntt.co.jp
2018-05-24 14:01:10 -04:00
Simon Riggs 08ea7a2291 Revert MERGE patch
This reverts commits d204ef6377,
83454e3c2b and a few more commits thereafter
(complete list at the end) related to MERGE feature.

While the feature was fully functional, with sufficient test coverage and
necessary documentation, it was felt that some parts of the executor and
parse-analyzer can use a different design and it wasn't possible to do that in
the available time. So it was decided to revert the patch for PG11 and retry
again in the future.

Thanks again to all reviewers and bug reporters.

List of commits reverted, in reverse chronological order:

 f1464c5380 Improve parse representation for MERGE
 ddb4158579 MERGE syntax diagram correction
 530e69e59b Allow cpluspluscheck to pass by renaming variable
 01b88b4df5 MERGE minor errata
 3af7b2b0d4 MERGE fix variable warning in non-assert builds
 a5d86181ec MERGE INSERT allows only one VALUES clause
 4b2d44031f MERGE post-commit review
 4923550c20 Tab completion for MERGE
 aa3faa3c7a WITH support in MERGE
 83454e3c2b New files for MERGE
 d204ef6377 MERGE SQL Command following SQL:2016

Author: Pavan Deolasee
Reviewed-by: Michael Paquier
2018-04-12 11:22:56 +01:00
Alvaro Herrera 851f4b4e14 Don't clone internal triggers to partitions
Trigger cloning to partitions was supposed to occur for user-visible
triggers only, but during development the protection that prevented it
from occurring to internal triggers was lost.  Reinstate it, as well as
add a test case to ensure internal triggers (in the tested case,
triggers implementing a deferred unique constraint) are not cloned.
Without the code fix, the partitions in the test end up with different
numbers of triggers, which is clearly wrong ...

Bug in 86f575948c.

Discussion: https://postgr.es/m/20180403214903.ozfagwjcpk337uw7@alvherre.pgsql
2018-04-03 19:08:25 -03:00
Simon Riggs d204ef6377 MERGE SQL Command following SQL:2016
MERGE performs actions that modify rows in the target table
using a source table or query. MERGE provides a single SQL
statement that can conditionally INSERT/UPDATE/DELETE rows
a task that would other require multiple PL statements.
e.g.

MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
  UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
  DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
  INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
  DO NOTHING;

MERGE works with regular and partitioned tables, including
column and row security enforcement, as well as support for
row, statement and transition triggers.

MERGE is optimized for OLTP and is parameterizable, though
also useful for large scale ETL/ELT. MERGE is not intended
to be used in preference to existing single SQL commands
for INSERT, UPDATE or DELETE since there is some overhead.
MERGE can be used statically from PL/pgSQL.

MERGE does not yet support inheritance, write rules,
RETURNING clauses, updatable views or foreign tables.
MERGE follows SQL Standard per the most recent SQL:2016.

Includes full tests and documentation, including full
isolation tests to demonstrate the concurrent behavior.

This version written from scratch in 2017 by Simon Riggs,
using docs and tests originally written in 2009. Later work
from Pavan Deolasee has been both complex and deep, leaving
the lead author credit now in his hands.
Extensive discussion of concurrency from Peter Geoghegan,
with thanks for the time and effort contributed.

Various issues reported via sqlsmith by Andreas Seltenreich

Authors: Pavan Deolasee, Simon Riggs
Reviewer: Peter Geoghegan, Amit Langote, Tomas Vondra, Simon Riggs

Discussion:
https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
2018-04-03 09:28:16 +01:00
Simon Riggs 7cf8a5c302 Revert "Modified files for MERGE"
This reverts commit 354f13855e.
2018-04-02 21:34:15 +01:00
Simon Riggs 354f13855e Modified files for MERGE 2018-04-02 21:12:47 +01:00
Alvaro Herrera 186b6df2e6 Fix test impredictability
Test 'triggers' fails when another one creates triggers concurrently at
some precise time, because of a missing WHERE clause.

Per buildfarm members snapper, desmoxytes.
2018-03-26 11:46:04 -03:00
Alvaro Herrera 555ee77a96 Handle INSERT .. ON CONFLICT with partitioned tables
Commit eb7ed3f306 enabled unique constraints on partitioned tables,
but one thing that was not working properly is INSERT/ON CONFLICT.
This commit introduces a new node keeps state related to the ON CONFLICT
clause per partition, and fills it when that partition is about to be
used for tuple routing.

Author: Amit Langote, Álvaro Herrera
Reviewed-by: Etsuro Fujita, Pavan Deolasee
Discussion: https://postgr.es/m/20180228004602.cwdyralmg5ejdqkq@alvherre.pgsql
2018-03-26 10:43:54 -03:00
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 25b692568f Prevent dangling-pointer access when update trigger returns old tuple.
A before-update row trigger may choose to return the "new" or "old" tuple
unmodified.  ExecBRUpdateTriggers failed to consider the second
possibility, and would proceed to free the "old" tuple even if it was the
one returned, leading to subsequent access to already-deallocated memory.
In debug builds this reliably leads to an "invalid memory alloc request
size" failure; in production builds it might accidentally work, but data
corruption is also possible.

This is a very old bug.  There are probably a couple of reasons it hasn't
been noticed up to now.  It would be more usual to return NULL if one
wanted to suppress the update action; returning "old" is significantly less
efficient since the update will occur anyway.  Also, none of the standard
PLs would ever cause this because they all returned freshly-manufactured
tuples even if they were just copying "old".  But commit 4b93f5799 changed
that for plpgsql, making it possible to see the bug with a plpgsql trigger.
Still, this is certainly legal behavior for a trigger function, so it's
ExecBRUpdateTriggers's fault not plpgsql's.

It seems worth creating a test case that exercises returning "old" directly
with a C-language trigger; testing this through plpgsql seems unreliable
because its behavior might change again.

Report and fix by Rushabh Lathia; regression test case by me.
Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAGPqQf1P4pjiNPrMof=P_16E-DFjt457j+nH2ex3=nBTew7tXw@mail.gmail.com
2018-02-27 13:28:02 -05:00
Tom Lane db3af9feb1 Remove unused functions in regress.c.
This patch removes five functions that presumably were once used in the
regression tests, but haven't been so used in many years.  Nonetheless
we've been wasting maintenance effort on them (e.g., by converting them
to V1 function protocol).  I see no reason to think that reviving them
would add any useful test coverage, so drop 'em.

In passing, mark regress_lseg_construct static, since it's not called
from outside this file.

Discussion: https://postgr.es/m/29322.1519701006@sss.pgh.pa.us
2018-02-27 11:11:25 -05:00
Tom Lane 3d2aed664e Avoid using unsafe search_path settings during dump and restore.
Historically, pg_dump has "set search_path = foo, pg_catalog" when
dumping an object in schema "foo", and has also caused that setting
to be used while restoring the object.  This is problematic because
functions and operators in schema "foo" could capture references meant
to refer to pg_catalog entries, both in the queries issued by pg_dump
and those issued during the subsequent restore run.  That could
result in dump/restore misbehavior, or in privilege escalation if a
nefarious user installs trojan-horse functions or operators.

This patch changes pg_dump so that it does not change the search_path
dynamically.  The emitted restore script sets the search_path to what
was used at dump time, and then leaves it alone thereafter.  Created
objects are placed in the correct schema, regardless of the active
search_path, by dint of schema-qualifying their names in the CREATE
commands, as well as in subsequent ALTER and ALTER-like commands.

Since this change requires a change in the behavior of pg_restore
when processing an archive file made according to this new convention,
bump the archive file version number; old versions of pg_restore will
therefore refuse to process files made with new versions of pg_dump.

Security: CVE-2018-1058
2018-02-26 10:18:21 -05:00
Alvaro Herrera cef60043dd Mention trigger name in trigger test
This makes it more explicit exactly what is going on, for further
proposed behavior changes.

Discussion: https://postgr.es/m/20180214212624.hm7of76flesodamf@alvherre.pgsql
2018-02-17 13:18:34 -03:00
Peter Eisentraut 7c44b75a2a Make new triggers tests more robust
Add explicit collation on the trigger name to avoid locale dependencies.
Also restrict the tables selected, to avoid interference from
concurrently running tests.
2018-02-07 14:57:19 -05:00