In the latest version of Apple's macOS SDK, <sys/socket.h>
fails to compile if "REF" is #define'd as something.
Apple may or may not agree that this is a bug, and even if
they do accept the bug report I filed, they probably won't
fix it very quickly. In the meantime, our back branches will all
fail to compile gram.y. v15 and HEAD currently escape the problem
thanks to the refactoring done in 98e93a1fc, but that's purely
accidental. Moreover, since that patch removed a widely-visible
inclusion of <netdb.h>, back-patching it seems too likely to break
third-party code.
Instead, change the token's code name to REF_P, following our usual
convention for naming parser tokens that are likely to have symbol
conflicts. The effects of that should be localized to the grammar
and immediately surrounding files, so it seems like a safer answer.
Per project policy that we want to keep recently-out-of-support
branches buildable on modern systems, back-patch all the way to 9.2.
Discussion: https://postgr.es/m/1803927.1665938411@sss.pgh.pa.us
clang 15+ will issue a set-but-not-used warning when the only
use of a variable is in autoincrements (e.g., "foo++;").
That's perfectly sensible, but it detects a few more cases that
we'd not noticed before. Silence the warnings with our usual
methods, such as PG_USED_FOR_ASSERTS_ONLY, or in one case by
actually removing a useless variable.
One thing that we can't nicely get rid of is that with %pure-parser,
Bison emits "yynerrs" as a local variable that falls foul of this
warning. To silence those, I inserted "(void) yynerrs;" in the
top-level productions of affected grammars.
Per recently-established project policy, this is a candidate
for back-patching into out-of-support branches: it suppresses
annoying compiler warnings but changes no behavior. Hence,
back-patch to 9.5, which is as far as these patches go without
issues. (A preliminary check shows that the prior branches
need some other set-but-not-used cleanups too, so I'll leave
them for another day.)
Discussion: https://postgr.es/m/514615.1663615243@sss.pgh.pa.us
Most parts of the parser can expect that the stack overflow check
in transformExprRecurse() will trigger before things get desperate.
However, transformFromClauseItem() can recurse directly to self
without having analyzed any expressions, so it's possible to drive
it to a stack-overrun crash. Add a check to prevent that.
Per bug #17583 from Egor Chindyaskin. Back-patch to all supported
branches.
Richard Guo
Discussion: https://postgr.es/m/17583-33be55b9f981f75c@postgresql.org
Previously, if an extension script did CREATE OR REPLACE and there was
an existing object not belonging to the extension, it would overwrite
the object and adopt it into the extension. This is problematic, first
because the overwrite is probably unintentional, and second because we
didn't change the object's ownership. Thus a hostile user could create
an object in advance of an expected CREATE EXTENSION command, and would
then have ownership rights on an extension object, which could be
modified for trojan-horse-type attacks.
Hence, forbid CREATE OR REPLACE of an existing object unless it already
belongs to the extension. (Note that we've always forbidden replacing
an object that belongs to some other extension; only the behavior for
previously-free-standing objects changes here.)
For the same reason, also fail CREATE IF NOT EXISTS when there is
an existing object that doesn't belong to the extension.
Our thanks to Sven Klemm for reporting this problem.
Security: CVE-2022-2625
I thought commit fd96d14d9 had plugged all the holes of this sort,
but no, function RTEs could produce oversize tuples too, either
via long coldeflists or just from multiple functions in one RTE.
(I'm pretty sure the other variants of base RTEs aren't a problem,
because they ultimately refer to either a table or a sub-SELECT,
whose widths are enforced elsewhere. But we explicitly allow join
RTEs to be overwidth, as long as you don't try to form their
tuple result.)
Per further discussion of bug #17561. As before, patch all branches.
Discussion: https://postgr.es/m/17561-80350151b9ad2ad4@postgresql.org
A RowExpr with more than MaxTupleAttributeNumber columns would fail at
execution anyway, since we cannot form a tuple datum with more than that
many columns. While heap_form_tuple() has a check for too many columns,
it emerges that there are some intermediate bits of code that don't
check and can be driven to failure with sufficiently many columns.
Checking this at parse time seems like the most appropriate place to
install a defense, since we already check SELECT list length there.
While at it, make the SELECT-list-length error use the same errcode
(TOO_MANY_COLUMNS) as heap_form_tuple does, rather than the generic
PROGRAM_LIMIT_EXCEEDED.
Per bug #17561 from Egor Chindyaskin. The given test case crashes
in all supported branches (and probably a lot further back),
so patch all.
Discussion: https://postgr.es/m/17561-80350151b9ad2ad4@postgresql.org
Due to lack of concern for the case in the dependency code, it's
possible to drop a column of a composite type even though stored
queries have references to the dropped column via functions-in-FROM
that return the composite type. There are "soft" references,
namely FROM-clause aliases for such columns, and "hard" references,
that is actual Vars referring to them. The right fix for hard
references is to add dependencies preventing the drop; something
we've known for many years and not done (and this commit still doesn't
address it). A "soft" reference shouldn't prevent a drop though.
We've been around on this before (cf. 9b35ddce9, 2c4debbd0), but
nobody had noticed that the current behavior can result in dump/reload
failures, because ruleutils.c can print more column aliases than the
underlying composite type now has. So we need to rejigger the
column-alias-handling code to treat such columns as dropped and not
print aliases for them.
Rather than writing new code for this, I used expandRTE() which already
knows how to figure out which function result columns are dropped.
I'd initially thought maybe we could use expandRTE() in all cases, but
that fails for EXPLAIN's purposes, because the planner strips a lot of
RTE infrastructure that expandRTE() needs. So this patch just uses it
for unplanned function RTEs and otherwise does things the old way.
If there is a hard reference (Var), then removing the column alias
causes us to fail to print the Var, since there's no longer a name
to print. Failing seems less desirable than printing a made-up
name, so I made it print "?dropped?column?" instead.
Per report from Timo Stolz. Back-patch to all supported branches.
Discussion: https://postgr.es/m/5c91267e-3b6d-5795-189c-d15a55d61dbb@nullachtvierzehn.de
When locking a specific named relation for a FOR [KEY] UPDATE/SHARE
clause, transformLockingClause() finds the relation to lock by
scanning the rangetable for an RTE with a matching eref->aliasname.
However, it failed to account for the visibility rules of a join RTE.
If a join RTE doesn't have a user-supplied alias, it will have a
generated eref->aliasname of "unnamed_join" that is not visible as a
relation name in the parse namespace. Such an RTE needs to be skipped,
otherwise it might be found in preference to a regular base relation
with a user-supplied alias of "unnamed_join", preventing it from being
locked.
In addition, if a join RTE doesn't have a user-supplied alias, but
does have a join_using_alias, then the RTE needs to be matched using
that alias rather than the generated eref->aliasname, otherwise a
misleading "relation not found" error will be reported rather than a
"join cannot be locked" error.
Backpatch all the way, except for the second part which only goes back
to 14, where JOIN USING aliases were added.
Dean Rasheed, reviewed by Tom Lane.
Discussion: https://postgr.es/m/CAEZATCUY_KOBnqxbTSPf=7fz9HWPnZ5Xgb9SwYzZ8rFXe7nb=w@mail.gmail.com
We weren't checking the length of the column list in the alias clause of
an XMLTABLE or JSON_TABLE function (a "tablefunc" RTE), and it was
possible to make the server crash by passing an overly long one. Fix it
by throwing an error in that case, like the other places that deal with
alias lists.
In passing, modify the equivalent test used for join RTEs to look like
the other ones, which was different for no apparent reason.
This bug came in when XMLTABLE was born in version 10; backpatch to all
stable versions.
Reported-by: Wang Ke <krking@zju.edu.cn>
Discussion: https://postgr.es/m/17480-1c9d73565bb28e90@postgresql.org
The parser code that transformed VALUES from row-oriented to
column-oriented lists failed if there were zero columns.
You can't write that straightforwardly (though probably you
should be able to), but the case can be reached by expanding
a "tab.*" reference to a zero-column table.
Per bug #17477 from Wang Ke. Back-patch to all supported branches.
Discussion: https://postgr.es/m/17477-0af3c6ac6b0a6ae0@postgresql.org
Don't try to look at the attidentity field of system attributes,
because they're not there in the TupleDescAttr array. Sometimes
this is harmless because we accidentally pick up a zero, but
otherwise we'll report "no owned sequence found" from an attempt
to alter a system attribute. (It seems possible that a SIGSEGV
could occur, too, though I've not seen it in testing.)
It's not in this function's charter to complain that you can't
alter a system column, so instead just hard-wire an assumption
that system attributes aren't identities. I didn't bother with
a regression test because the appearance of the bug is very
erratic.
Per bug #17465 from Roman Zharkov. Back-patch to all supported
branches. (There's not actually a live bug before v12, because
before that get_attidentity() did the right thing anyway.
But for consistency I changed the test in the older branches too.)
Discussion: https://postgr.es/m/17465-f2a554a6cb5740d3@postgresql.org
Fix the code changed by commit 5c056b0c2 so that we always generate
RelabelType, not something else, for a cast to unspecified typmod.
Otherwise planner optimizations might not happen.
It appears we missed this point because the previous experiments were
done on type numeric: the parser undesirably generates a call on the
numeric() length-coercion function, but then numeric_support()
optimizes that down to a RelabelType, so that everything seems fine.
It misbehaves for types that have a non-optimized length coercion
function, such as bpchar.
Per report from John Naylor. Back-patch to all supported branches,
as the previous patch eventually was. Unfortunately, that no longer
includes 9.6 ... we really shouldn't put this type of change into a
nearly-EOL branch.
Discussion: https://postgr.es/m/CAFBsxsEfbFHEkouc+FSj+3K1sHipLPbEC67L0SAe-9-da8QtYg@mail.gmail.com
I think when I added this assertion (in commit 8f889b108), I was only
thinking of the use of transformExpressionList at top level of INSERT
and VALUES. But it's also called by transformRowExpr(), which can
certainly occur in an UPDATE targetlist, so it's inappropriate to
suppose that p_multiassign_exprs must be empty. Besides, since the
input is not expected to contain ResTargets, there's no reason it
should contain MultiAssignRefs either. Hence this code need not
be concerned about the state of p_multiassign_exprs, and we should
just drop the assertion.
Per bug #17236 from ocean_li_996. It's been wrong for years,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/17236-3210de9bcba1d7ca@postgresql.org
Casting a value that's already of a type with a specific typmod
to an unspecified typmod doesn't do anything so far as run-time
behavior is concerned. However, it really ought to change the
exposed type of the expression to match. Up to now,
coerce_type_typmod hasn't bothered with that, which creates gotchas
in contexts such as recursive unions. If for example one side of
the union is numeric(18,3), but it needs to be plain numeric to
match the other side, there's no direct way to express that.
This is easy enough to fix, by inserting a RelabelType to update the
exposed type of the expression. However, it's a bit nervous-making
to change this behavior, because it's stood for a really long time.
But no complaints have emerged about 14beta3, so go ahead and
back-patch.
Back-patch of 5c056b0c2 into previous supported branches.
Discussion: https://postgr.es/m/CABNQVagu3bZGqiTjb31a8D5Od3fUMs7Oh3gmZMQZVHZ=uWWWfQ@mail.gmail.com
Discussion: https://postgr.es/m/1488389.1631984807@sss.pgh.pa.us
There are two identical error messages about valid value of modulus for
hash partition, in PostgreSQL source code. Commit 0e1275fb07 improved
only one of them so that ambiguous word "positive" was avoided there,
and forgot to improve the other. This commit improves the other.
Which would reduce translator burden.
Back-pach to v11 where the error message exists.
Author: Kyotaro Horiguchi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/20210819.170315.1413060634876301811.horikyota.ntt@gmail.com
transformLockingClause neglected to exclude the pseudo-RTEs for
OLD/NEW when processing a rule's query. This led to odd errors
or even crashes later on. This bug is very ancient, but it's
not terribly surprising that nobody noticed, since the use-case
for SELECT FOR UPDATE in a non-view rule is somewhere between
thin and non-existent. Still, crashing is not OK.
Per bug #17151 from Zhiyong Wu. Thanks to Masahiko Sawada
for analysis of the problem.
Discussion: https://postgr.es/m/17151-c03a3e6e4ec9aadb@postgresql.org
Recursion into the FILTER clause was mis-implemented, such that a
relevant Var or Aggref at the very top of the FILTER clause would
be ignored. (Of course, that'd have to be a plain boolean Var or
boolean-returning aggregate.) The consequence would be
mis-identification of the correct semantic level of the aggregate,
which could lead to not-per-spec query behavior. If the FILTER
expression is an aggregate, this could also lead to failure to issue
an expected "aggregate function calls cannot be nested" error, which
would likely result in a core dump later on, since the planner and
executor aren't expecting such cases to appear.
The root cause is that commit b560ec1b0 blindly copied some code
that assumed it's recursing into a List, and thus didn't examine the
top-level node. To forestall questions about why this call doesn't
look like the others, as well as possible future copy-and-paste
mistakes, let's change all three check_agg_arguments_walker calls in
check_agg_arguments, even though only the one for the filter clause
is really broken.
Per bug #17152 from Zhiyong Wu. This has been wrong since we
implemented FILTER, so back-patch to all supported versions.
(Testing suggests that pre-v11 branches manage to avoid crashing
in the bad-Aggref case, thanks to "redundant" checks in ExecInitAgg.
But I'm not sure how thorough that protection is, and anyway the
wrong-behavior issue remains, so fix 9.6 and 10 too.)
Discussion: https://postgr.es/m/17152-c7f906cc1a88e61b@postgresql.org
This case should be disallowed, just as FOR UPDATE with a plain
GROUP BY is disallowed; FOR UPDATE only makes sense when each row
of the query result can be identified with a single table row.
However, we missed teaching CheckSelectLocking() to check
groupingSets as well as groupClause, so that it would allow
degenerate grouping sets. That resulted in a bad plan and
a null-pointer dereference in the executor.
Looking around for other instances of the same bug, the only one
I found was in examine_simple_variable(). That'd just lead to
silly estimates, but it should be fixed too.
Per private report from Yaoguang Chen.
Back-patch to all supported branches.
There are hacks in parse_coerce.c to push down a requested coercion
to below any CollateExpr that may appear. However, we did that even
if the requested data type is non-collatable, leading to an invalid
expression tree in which CollateExpr is applied to a non-collatable
type. The fix is just to drop the CollateExpr altogether, reasoning
that it's useless.
This bug is ten years old, dating to the original addition of
COLLATE support. The lack of field complaints suggests that there
aren't a lot of user-visible consequences. We noticed the problem
because it would trigger an assertion in DefineVirtualRelation if
the invalid structure appears as an output column of a view; however,
in a non-assert build, you don't see a crash just a (subtly incorrect)
complaint about applying collation to a non-collatable type. I found
that by putting the incorrect structure further down in a view, I could
make a view definition that would fail dump/reload, per the added
regression test case. But CollateExpr doesn't do anything at run-time,
so this likely doesn't lead to any really exciting consequences.
Per report from Yulin Pei. Back-patch to all supported branches.
Discussion: https://postgr.es/m/HK0PR01MB22744393C474D503E16C8509F4709@HK0PR01MB2274.apcprd01.prod.exchangelabs.com
GENERATED ALWAYS AS IDENTITY implies NOT NULL, but the code failed
to complain if you overrode that with "GENERATED ALWAYS AS IDENTITY
NULL". One might think the old behavior was a feature, but it was
inconsistent because the outcome varied depending on the order of
the clauses, so it seems to have been just an oversight.
Per bug #16913 from Pavel Boev. Back-patch to v10 where identity
columns were introduced.
Vik Fearing (minor tweaks by me)
Discussion: https://postgr.es/m/16913-3b5198410f67d8c6@postgresql.org
As it stood, expandTableLikeClause() re-did the same relation_openrv
call that transformTableLikeClause() had done. However there are
scenarios where this would not find the same table as expected.
We hold lock on the LIKE source table, so it can't be renamed or
dropped, but another table could appear before it in the search path.
This explains the odd behavior reported in bug #16758 when cloning a
table as a temp table of the same name. This case worked as expected
before commit 502898192 introduced the need to open the source table
twice, so we should fix it.
To make really sure we get the same table, let's re-open it by OID not
name. That requires adding an OID field to struct TableLikeClause,
which is a little nervous-making from an ABI standpoint, but as long
as it's at the end I don't think there's any serious risk.
Per bug #16758 from Marc Boeren. Like the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16758-840e84a6cfab276d@postgresql.org
Commit 502898192 was too careless about the order of execution of the
additional ALTER TABLE operations generated by expandTableLikeClause.
It just stuck them all at the end, which seems okay for most purposes.
But it falls down in the case where LIKE is importing a primary key
or unique index and the outer CREATE TABLE includes a FOREIGN KEY
constraint that needs to depend on that index. Weird as that is,
it used to work, so we ought to keep it working.
To fix, make parse_utilcmd.c insert LIKE clauses between index-creation
and FK-creation commands in the transformed list of commands, and change
utility.c so that the commands generated by expandTableLikeClause are
executed immediately not at the end. One could imagine scenarios where
this wouldn't work either; but currently expandTableLikeClause only
makes column default expressions, CHECK constraints, and indexes, and
this ordering seems fine for those.
Per bug #16730 from Sofoklis Papasofokli. Like the previous patch,
back-patch to all supported branches.
Discussion: https://postgr.es/m/16730-b902f7e6e0276b30@postgresql.org
It's unsafe to do this at parse time because addition of generated
columns to a table would not invalidate stored rules containing
UPDATEs on the table ... but there might now be dependent generated
columns that were not there when the rule was made. This also fixes
an oversight that rewriteTargetView failed to update extraUpdatedCols
when transforming an UPDATE on an updatable view. (Since the new
calculation is downstream of that, rewriteTargetView doesn't actually
need to do anything; but before, there was a demonstrable bug there.)
In v13 and HEAD, this leads to easily-visible bugs because (since
commit c6679e4fc) we won't recalculate generated columns that aren't
listed in extraUpdatedCols. In v12 this bitmap is mostly just used
for trigger-firing decisions, so you'd only notice a problem if a
trigger cared whether a generated column had been updated.
I'd complained about this back in May, but then forgot about it
until bug #16671 from Michael Paul Killian revived the issue.
Back-patch to v12 where this field was introduced. If existing
stored rules contain any extraUpdatedCols values, they'll be
ignored because the rewriter will overwrite them, so the bug will
be fixed even for existing rules. (But note that if someone were
to update to 13.1 or 12.5, store some rules with UPDATEs on tables
having generated columns, and then downgrade to a prior minor version,
they might observe issues similar to what this patch fixes. That
seems unlikely enough to not be worth going to a lot of effort to fix.)
Discussion: https://postgr.es/m/10206.1588964727@sss.pgh.pa.us
Discussion: https://postgr.es/m/16671-2fa55851859fb166@postgresql.org
It appears that commit cf63c641c, which intended to prevent
misoptimization of the result-building step in makeOrderedSetArgs,
didn't go far enough: buildfarm member hornet's version of xlc
is now optimizing back to the old, broken behavior in which
list_length(directargs) is fetched only after list_concat() has
changed that value. I'm not entirely convinced whether that's
an undeniable compiler bug or whether it can be justified by a
sufficiently aggressive interpretation of C sequence points.
So let's just change the code to make it harder to misinterpret.
Back-patch to all supported versions, just in case.
Discussion: https://postgr.es/m/1830491.1601944935@sss.pgh.pa.us
If a CREATE TABLE command uses both LIKE and traditional inheritance,
Vars in CHECK constraints and expression indexes that are absorbed
from a LIKE parent table tended to get mis-numbered, resulting in
wrong answers and/or bizarre error messages (though probably not any
actual crashes, thanks to validation occurring in the executor).
In v12 and up, the same could happen to Vars in GENERATED expressions,
even in cases with no LIKE clause but multiple traditional-inheritance
parents.
The cause of the problem for LIKE is that parse_utilcmd.c supposed
it could renumber such Vars correctly during transformCreateStmt(),
which it cannot since we have not yet accounted for columns added via
inheritance. Fix that by postponing processing of LIKE INCLUDING
CONSTRAINTS, DEFAULTS, GENERATED, INDEXES till after we've performed
DefineRelation().
The error with GENERATED and multiple inheritance is a simple oversight
in MergeAttributes(); it knows it has to renumber Vars in inherited
CHECK constraints, but forgot to apply the same processing to inherited
GENERATED expressions (a/k/a defaults).
Per bug #16272 from Tom Gottfried. The non-GENERATED variants of the
issue are ancient, presumably dating right back to the addition of
CREATE TABLE LIKE; hence back-patch to all supported branches.
Discussion: https://postgr.es/m/16272-6e32da020e9a9381@postgresql.org
CREATE TABLE LIKE INCLUDING GENERATED would fail if a generated column
referred to a column with a higher attribute number. This is because
the column mapping mechanism created the mapping incrementally as
columns are added. This was sufficient for previous uses of that
mechanism (omitting dropped columns), and it also happened to work if
generated columns only referred to columns with lower attribute
numbers, but here it failed.
This fix is to build the attribute mapping in a separate loop before
processing the columns in detail.
Bug: #16342
Reported-by: Ethan Waldo <ewaldo@healthetechs.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Attempting to use a COLLATE clause with a type that it not collatable in
a partition bound expression could crash the server. This commit fixes
the code by adding more checks similar to what is done when computing
index or partition attributes by making sure that there is a collation
iff the type is collatable.
Backpatch down to 12, as 7c079d7 introduced this problem.
Reported-by: Alexander Lakhin
Author: Dmitry Dolgov
Discussion: https://postgr.es/m/16325-809194cf742313ab@postgresql.org
Backpatch-through: 12
Until now, only selected bulk operations (e.g. COPY) did this. If a
given relfilenode received both a WAL-skipping COPY and a WAL-logged
operation (e.g. INSERT), recovery could lose tuples from the COPY. See
src/backend/access/transam/README section "Skipping WAL for New
RelFileNode" for the new coding rules. Maintainers of table access
methods should examine that section.
To maintain data durability, just before commit, we choose between an
fsync of the relfilenode and copying its contents to WAL. A new GUC,
wal_skip_threshold, guides that choice. If this change slows a workload
that creates small, permanent relfilenodes under wal_level=minimal, try
adjusting wal_skip_threshold. Users setting a timeout on COMMIT may
need to adjust that timeout, and log_min_duration_statement analysis
will reflect time consumption moving to COMMIT from commands like COPY.
Internally, this requires a reliable determination of whether
RollbackAndReleaseCurrentSubTransaction() would unlink a relation's
current relfilenode. Introduce rd_firstRelfilenodeSubid. Amend the
specification of rd_createSubid such that the field is zero when a new
rel has an old rd_node. Make relcache.c retain entries for certain
dropped relations until end of transaction.
Back-patch to 9.5 (all supported versions). This introduces a new WAL
record type, XLOG_GIST_ASSIGN_LSN, without bumping XLOG_PAGE_MAGIC. As
always, update standby systems before master systems. This changes
sizeof(RelationData) and sizeof(IndexStmt), breaking binary
compatibility for affected extensions. (The most recent commit to
affect the same class of extensions was
089e4d405d0f3b94c74a2c6a54357a84a681754b.)
Kyotaro Horiguchi, reviewed (in earlier, similar versions) by Robert
Haas. Heikki Linnakangas and Michael Paquier implemented earlier
designs that materially clarified the problem. Reviewed, in earlier
designs, by Andrew Dunstan, Andres Freund, Alvaro Herrera, Tom Lane,
Fujii Masao, and Simon Riggs. Reported by Martijn van Oosterhout.
Discussion: https://postgr.es/m/20150702220524.GA9392@svana.org
Using ALTER TABLE ATTACH PARTITION causes an assertion failure when
attempting to work on a partitioned index, because partitioned indexes
cannot have partition bounds.
The grammar of ALTER TABLE ATTACH PARTITION requires partition bounds,
but not ALTER INDEX, so mixing ALTER TABLE with partitioned indexes is
confusing. Hence, on HEAD, prevent ALTER TABLE to attach a partition if
the relation involved is a partitioned index. On back-branches, as
applications may rely on the existing behavior, just remove the
culprit assertion.
Reported-by: Alexander Lakhin
Author: Amit Langote, Michael Paquier
Discussion: https://postgr.es/m/16276-5cd1dcc8fb8be7b5@postgresql.org
Backpatch-through: 11
The extraUpdatedCols field of the target RTE records which generated
columns are affected by an update. This is used in a variety of
places, including per-column triggers and foreign data wrappers. When
an update was initiated by a logical replication subscription, this
field was not filled in, so such an update would not affect generated
columns in a way that is consistent with normal updates. To fix,
factor out some code from analyze.c to fill in extraUpdatedCols in the
logical replication worker as well.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b05e781a-fa16-6b52-6738-761181204567@2ndquadrant.com
LIKE INCLUDING DEFAULTS tried to copy the attrdef expression without
copying the state of the attgenerated column. This is in fact wrong,
because GENERATED and DEFAULT expressions are not the same kind of animal;
one can contain Vars and the other not. We *must* copy attgenerated
when we're copying the attrdef expression. Rearrange the if-tests
so that the expression is copied only when the correct one of
INCLUDING DEFAULTS and INCLUDING GENERATED has been specified.
Per private report from Manuel Rigger.
Tom Lane and Peter Eisentraut
Commit aa27977fe2 introduced this
restriction for pg_temp.function_name(arg); do likewise for types
created in temporary schemas. Programs that this breaks should add
"pg_temp." schema qualification or switch to arg::type_name syntax.
Back-patch to 9.4 (all supported versions).
Reviewed by Tom Lane. Reported by Tom Lane.
Security: CVE-2019-10208
One would have needed out-of-tree code to observe the defects. Remove
unreferenced fields instead of completing their support functions.
Since in-tree code can't reach _readIntoClause(), no catversion bump.
This is still using the 2.0 version of pg_bsd_indent.
I thought it would be good to commit this separately,
so as to document the differences between 2.0 and 2.1 behavior.
Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
Commit 41b54ba78e allowed existing VACUUM options to take a boolean
argument. It's documented that valid boolean values that VACUUM can
accept are true, false, on, off, 1, and 0. But previously the parser
failed to accept 1 and 0 as a boolean value in VACUUM syntax because
of a lack of NumericOnly clause for vac_analyze_option_arg in gram.y.
This commit adds such NumericOnly clause so that VACUUM options
can take also 1 and 0 as a boolean value.
Discussion: https://postgr.es/m/CAHGQGwGYg82A8UCQxZe7Zn9MnyUBGdyB=1CNpKF3jBny+RbyfA@mail.gmail.com
Commit ca4103025d left a few loose ends. The most important one
(broken pg_dump output) is already fixed by virtue of commit
3b23552ad8, but some things remained:
* When ALTER TABLE rewrites tables, the indexes must remain in the
tablespace they were originally in. This didn't work because
index recreation during ALTER TABLE runs manufactured SQL (yuck),
which runs afoul of default_tablespace in competition with the parent
relation tablespace. To fix, reset default_tablespace to the empty
string temporarily, and add the TABLESPACE clause as appropriate.
* Setting a partitioned rel's tablespace to the database default is
confusing; if it worked, it would direct the partitions to that
tablespace regardless of default_tablespace. But in reality it does
not work, and making it work is a larger project. Therefore, throw
an error when this condition is detected, to alert the unwary.
Add some docs and tests, too.
Author: Álvaro Herrera
Discussion: https://postgr.es/m/CAKJS1f_1c260nOt_vBJ067AZ3JXptXVRohDVMLEBmudX1YEx-A@mail.gmail.com
Up to now, DefineIndex() was responsible for adding attnotnull constraints
to the columns of a primary key, in any case where it hadn't been
convenient for transformIndexConstraint() to mark those columns as
is_not_null. It (or rather its minion index_check_primary_key) did this
by executing an ALTER TABLE SET NOT NULL command for the target table.
The trouble with this solution is that if we're creating the index due
to ALTER TABLE ADD PRIMARY KEY, and the outer ALTER TABLE has additional
sub-commands, the inner ALTER TABLE's operations executed at the wrong
time with respect to the outer ALTER TABLE's operations. In particular,
the inner ALTER would perform a validation scan at a point where the
table's storage might be inconsistent with its catalog entries. (This is
on the hairy edge of being a security problem, but AFAICS it isn't one
because the inner scan would only be interested in the tuples' null
bitmaps.) This can result in unexpected failures, such as the one seen
in bug #15580 from Allison Kaptur.
To fix, let's remove the attempt to do SET NOT NULL from DefineIndex(),
reducing index_check_primary_key's role to verifying that the columns are
already not null. (It shouldn't ever see such a case, but it seems wise
to keep the check for safety.) Instead, make transformIndexConstraint()
generate ALTER TABLE SET NOT NULL subcommands to be executed ahead of
the ADD PRIMARY KEY operation in every case where it can't force the
column to be created already-not-null. This requires only minor surgery
in parse_utilcmd.c, and it makes for a much more satisfying spec for
transformIndexConstraint(): it's no longer having to take it on faith
that someone else will handle addition of NOT NULL constraints.
To make that work, we have to move the execution of AT_SetNotNull into
an ALTER pass that executes ahead of AT_PASS_ADD_INDEX. I moved it to
AT_PASS_COL_ATTRS, and put that after AT_PASS_ADD_COL to avoid failure
when the column is being added in the same command. This incidentally
fixes a bug in the only previous usage of AT_PASS_COL_ATTRS, for
AT_SetIdentity: it didn't work either for a newly-added column.
Playing around with this exposed a separate bug in ALTER TABLE ONLY ...
ADD PRIMARY KEY for partitioned tables. The intent of the ONLY modifier
in that context is to prevent doing anything that would require holding
lock for a long time --- but the implied SET NOT NULL would recurse to
the child partitions, and do an expensive validation scan for any child
where the column(s) were not already NOT NULL. To fix that, invent a
new ALTER subcommand AT_CheckNotNull that just insists that a child
column be already NOT NULL, and apply that, not AT_SetNotNull, when
recursing to children in this scenario. This results in a slightly laxer
definition of ALTER TABLE ONLY ... SET NOT NULL for partitioned tables,
too: that command will now work as long as all children are already NOT
NULL, whereas before it just threw up its hands if there were any
partitions.
In passing, clean up the API of generateClonedIndexStmt(): remove a
useless argument, ensure that the output argument is not left undefined,
update the header comment.
A small side effect of this change is that no-such-column errors in ALTER
TABLE ADD PRIMARY KEY now produce a different message that includes the
table name, because they are now detected by the SET NOT NULL step which
has historically worded its error that way. That seems fine to me, so
I didn't make any effort to avoid the wording change.
The basic bug #15580 is of very long standing, and these other bugs
aren't new in v12 either. However, this is a pretty significant change
in the way ALTER TABLE ADD PRIMARY KEY works. On balance it seems best
not to back-patch, at least not till we get some more confidence that
this patch has no new bugs.
Patch by me, but thanks to Jie Zhang for a preliminary version.
Discussion: https://postgr.es/m/15580-d1a6de5a3d65da51@postgresql.org
Discussion: https://postgr.es/m/1396E95157071C4EBBA51892C5368521017F2E6E63@G08CNEXMBPEKD02.g08.fujitsu.local
The syntax
GENERATED BY DEFAULT AS (expr)
is not allowed but we have to accept it in the grammar to avoid
shift/reduce conflicts because of the similar syntax for identity
columns. The existing code just ignored this, incorrectly. Add an
explicit error check and a bespoke error message.
Reported-by: Justin Pryzby <pryzby@telsasoft.com>
This is an SQL-standard feature that allows creating columns that are
computed from expressions rather than assigned, similar to a view or
materialized view but on a column basis.
This implements one kind of generated column: stored (computed on
write). Another kind, virtual (computed on read), is planned for the
future, and some room is left for it.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/b151f851-4019-bdb1-699e-ebab07d2f40a@2ndquadrant.com
This adds the CONCURRENTLY option to the REINDEX command. A REINDEX
CONCURRENTLY on a specific index creates a new index (like CREATE
INDEX CONCURRENTLY), then renames the old index away and the new index
in place and adjusts the dependencies, and then drops the old
index (like DROP INDEX CONCURRENTLY). The REINDEX command also has
the capability to run its other variants (TABLE, DATABASE) with the
CONCURRENTLY option (but not SYSTEM).
The reindexdb command gets the --concurrently option.
Author: Michael Paquier, Andreas Karlsson, Peter Eisentraut
Reviewed-by: Andres Freund, Fujii Masao, Jim Nasby, Sergei Kornilov
Discussion: https://www.postgresql.org/message-id/flat/60052986-956b-4478-45ed-8bd119e9b9cf%402ndquadrant.com#74948a1044c56c5e817a5050f554ddee
Introduce a third extended statistic type, supported by the CREATE
STATISTICS command - MCV lists, a generalization of the statistic
already built and used for individual columns.
Compared to the already supported types (n-distinct coefficients and
functional dependencies), MCV lists are more complex, include column
values and allow estimation of much wider range of common clauses
(equality and inequality conditions, IS NULL, IS NOT NULL etc.).
Similarly to the other types, a new pseudo-type (pg_mcv_list) is used.
Author: Tomas Vondra
Reviewed-by: Dean Rasheed, David Rowley, Mark Dilger, Alvaro Herrera
Discussion: https://postgr.es/m/dfdac334-9cf2-2597-fb27-f0fb3753f435@2ndquadrant.com
Column references are not allowed in default expressions and partition
bound expressions, and are restricted as such once the transformation of
their expressions is done. However, trying to use more complex column
references can lead to confusing error messages. For example, trying to
use a two-field column reference name for default expressions and
partition bounds leads to "missing FROM-clause entry for table", which
makes no sense in their respective context.
In order to make the errors generated more useful, this commit adds more
verbose messages when transforming column references depending on the
context. This has a little consequence though: for example an
expression using an aggregate with a column reference as argument would
cause an error to be generated for the column reference, while the
aggregate was the problem reported before this commit because column
references get transformed first.
The confusion exists for default expressions for a long time, and the
problem is new as of v12 for partition bounds. Still per the lack of
complaints on the matter no backpatch is done.
The patch has been written by Amit Langote and me, and Tom Lane has
provided the improvement of the documentation for default expressions on
the CREATE TABLE page.
Author: Amit Langote, Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20190326020853.GM2558@paquier.xyz
