That makes the view a lot less disruptive to use on a production system.
Without the locks, you don't get a consistent snapshot across all buffers,
but that's OK. It wasn't a very useful guarantee in practice.
Ivan Kartyshov, reviewed by Tomas Vondra and Robert Haas.
Discusssion: <f9d6cab2-73a7-7a84-55a8-07dcb8516ae5@postgrespro.ru>
It's always been possible to create a zero-dimensional cube by converting
from a zero-length float8 array, but cube_in failed to accept the '()'
representation that cube_out produced for that case, resulting in a
dump/reload hazard. Make it accept the case. Also fix a couple of
other places that didn't behave sanely for zero-dimensional cubes:
cube_size would produce 1.0 when surely the answer should be 0.0,
and g_cube_distance risked a divide-by-zero failure.
Likewise, it's always been possible to create cubes containing float8
infinity or NaN coordinate values, but cube_in couldn't parse such input,
and cube_out produced platform-dependent spellings of the values. Convert
them to use float8in_internal and float8out_internal so that the behavior
will be the same as for float8, as we recently did for the core geometric
types (cf commit 50861cd68). As in that commit, I don't pretend that this
patch fixes all insane corner-case behaviors that may exist for NaNs, but
it's a step forward.
(This change allows removal of the separate cube_1.out and cube_3.out
expected-files, as the platform dependency that previously required them
is now gone: an underflowing coordinate value will now produce an error
not plus or minus zero.)
Make errors from cube_in follow project conventions as to spelling
("invalid input syntax for cube" not "bad cube representation")
and errcode (INVALID_TEXT_REPRESENTATION not SYNTAX_ERROR).
Also a few marginal code cleanups and comment improvements.
Tom Lane, reviewed by Amul Sul
Discussion: <15085.1472494782@sss.pgh.pa.us>
LibreSSL defines OPENSSL_VERSION_NUMBER to claim that it is version 2.0.0,
but it doesn't have the functions added in OpenSSL 1.1.0. Add autoconf
checks for the individual functions we need, and stop relying on
OPENSSL_VERSION_NUMBER.
Backport to 9.5 and 9.6, like the patch that broke this. In the
back-branches, there are still a few OPENSSL_VERSION_NUMBER checks left,
to check for OpenSSL 0.9.8 or 0.9.7. I left them as they were - LibreSSL
has all those functions, so they work as intended.
Per buildfarm member curculio.
Discussion: <2442.1473957669@sss.pgh.pa.us>
Otherwise, users who have configured shared_buffers >= 256GB won't
be able to use this module. There probably aren't many of those, but
it doesn't hurt anything to fix it so that it works.
Backpatch to 9.4, where MemoryContextAllocHuge was introduced. The
same problem exists in older branches, but there's no easy way to
fix it there.
KaiGai Kohei
Changes needed to build at all:
- Check for SSL_new in configure, now that SSL_library_init is a macro.
- Do not access struct members directly. This includes some new code in
pgcrypto, to use the resource owner mechanism to ensure that we don't
leak OpenSSL handles, now that we can't embed them in other structs
anymore.
- RAND_SSLeay() -> RAND_OpenSSL()
Changes that were needed to silence deprecation warnings, but were not
strictly necessary:
- RAND_pseudo_bytes() -> RAND_bytes().
- SSL_library_init() and OpenSSL_config() -> OPENSSL_init_ssl()
- ASN1_STRING_data() -> ASN1_STRING_get0_data()
- DH_generate_parameters() -> DH_generate_parameters()
- Locking callbacks are not needed with OpenSSL 1.1.0 anymore. (Good
riddance!)
Also change references to SSLEAY_VERSION_NUMBER with OPENSSL_VERSION_NUMBER,
for the sake of consistency. OPENSSL_VERSION_NUMBER has existed since time
immemorial.
Fix SSL test suite to work with OpenSSL 1.1.0. CA certificates must have
the "CA:true" basic constraint extension now, or OpenSSL will refuse them.
Regenerate the test certificates with that. The "openssl" binary, used to
generate the certificates, is also now more picky, and throws an error
if an X509 extension is specified in "req_extensions", but that section
is empty.
Backpatch to all supported branches, per popular demand. In back-branches,
we still support OpenSSL 0.9.7 and above. OpenSSL 0.9.6 should still work
too, but I didn't test it. In master, we only support 0.9.8 and above.
Patch by Andreas Karlsson, with additional changes by me.
Discussion: <20160627151604.GD1051@msg.df7cb.de>
Add a location field to the DefElem struct, used to parse many utility
commands. Update various error messages to supply error position
information.
To propogate the error position information in a more systematic way,
create a ParseState in standard_ProcessUtility() and pass that to
interested functions implementing the utility commands. This seems
better than passing the query string and then reassembling a parse state
ad hoc, which violates the encapsulation of the ParseState type.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
When building libpq, ip.c and md5.c were symlinked or copied from
src/backend/libpq into src/interfaces/libpq, but now that we have a
directory specifically for routines that are shared between the server and
client binaries, src/common/, move them there.
Some routines in ip.c were only used in the backend. Keep those in
src/backend/libpq, but rename to ifaddr.c to avoid confusion with the file
that's now in common.
Fix the comment in src/common/Makefile to reflect how libpq actually links
those files.
There are two more files that libpq symlinks directly from src/backend:
encnames.c and wchar.c. I don't feel compelled to move those right now,
though.
Patch by Michael Paquier, with some changes by me.
Discussion: <69938195-9c76-8523-0af8-eb718ea5b36e@iki.fi>
Where possible, use palloc or pg_malloc instead; otherwise, insert
explicit NULL checks.
Generally speaking, these are places where an actual OOM is quite
unlikely, either because they're in client programs that don't
allocate all that much, or they're very early in process startup
so that we'd likely have had a fork() failure instead. Hence,
no back-patch, even though this is nominally a bug fix.
Michael Paquier, with some adjustments by me
Discussion: <CAB7nPqRu07Ot6iht9i9KRfYLpDaF2ZuUv5y_+72uP23ZAGysRg@mail.gmail.com>
The previous API for this function had it returning a malloc'd string.
That meant that callers had to check for NULL return, which few of them
were doing, and it also meant that callers had to remember to free()
the string later, which required extra logic in most cases.
Instead, make simple_prompt() write into a buffer supplied by the caller.
Anywhere that the maximum required input length is reasonably small,
which is almost all of the callers, we can just use a local or static
array as the buffer instead of dealing with malloc/free.
A fair number of callers used "pointer == NULL" as a proxy for "haven't
requested the password yet". Maintaining the same behavior requires
adding a separate boolean flag for that, which adds back some of the
complexity we save by removing free()s. Nonetheless, this nets out
at a small reduction in overall code size, and considerably less code
than we would have had if we'd added the missing NULL-return checks
everywhere they were needed.
In passing, clean up the API comment for simple_prompt() and get rid
of a very-unnecessary malloc/free in its Windows code path.
This is nominally a bug fix, but it does not seem worth back-patching,
because the actual risk of an OOM failure in any of these places seems
pretty tiny, and all of them are client-side not server-side anyway.
This patch is by me, but it owes a great deal to Michael Paquier
who identified the problem and drafted a patch for fixing it the
other way.
Discussion: <CAB7nPqRu07Ot6iht9i9KRfYLpDaF2ZuUv5y_+72uP23ZAGysRg@mail.gmail.com>
OpenSSL officially only supports 1.0.1 and newer. Some OS distributions
still provide patches for 0.9.8, but anything older than that is not
interesting anymore. Let's simplify things by removing compatibility code.
Andreas Karlsson, with small changes by me.
I found that half a dozen (nearly 5%) of our AllocSetContextCreate calls
had typos in the context-sizing parameters. While none of these led to
especially significant problems, they did create minor inefficiencies,
and it's now clear that expecting people to copy-and-paste those calls
accurately is not a great idea. Let's reduce the risk of future errors
by introducing single macros that encapsulate the common use-cases.
Three such macros are enough to cover all but two special-purpose contexts;
those two calls can be left as-is, I think.
While this patch doesn't in itself improve matters for third-party
extensions, it doesn't break anything for them either, and they can
gradually adopt the simplified notation over time.
In passing, change TopMemoryContext to use the default allocation
parameters. Formerly it could only be extended 8K at a time. That was
probably reasonable when this code was written; but nowadays we create
many more contexts than we did then, so that it's not unusual to have a
couple hundred K in TopMemoryContext, even without considering various
dubious code that sticks other things there. There seems no good reason
not to let it use growing blocks like most other contexts.
Back-patch to 9.6, mostly because that's still close enough to HEAD that
it's easy to do so, and keeping the branches in sync can be expected to
avoid some future back-patching pain. The bugs fixed by these changes
don't seem to be significant enough to justify fixing them further back.
Discussion: <21072.1472321324@sss.pgh.pa.us>
You can use ALTER FOREIGN TABLE SET WITH OIDS on a foreign table, but the
oid column read out as zeros, because the postgres_fdw didn't know about
it. Teach postgres_fdw how to fetch it.
Etsuro Fujita, with an additional test case by me.
Discussion: <56E90A76.5000503@lab.ntt.co.jp>
As implemented, -e ran an EXPLAIN but then discarded the output, which
certainly seems pointless. Make it print to stdout instead. It's been
like that forever, so back-patch to all supported branches.
Daniel Gustafsson, reviewed by Andreas Scherbaum
Patch: <B97BDCB7-A3B3-4734-90B5-EDD586941629@yesql.se>
We implement a dozen or so parameterless functions that the SQL standard
defines special syntax for. Up to now, that was done by converting them
into more or less ad-hoc constructs such as "'now'::text::date". That's
messy for multiple reasons: it exposes what should be implementation
details to users, and performance is worse than it needs to be in several
cases. To improve matters, invent a new expression node type
SQLValueFunction that can represent any of these parameterless functions.
Bump catversion because this changes stored parsetrees for rules.
Discussion: <30058.1463091294@sss.pgh.pa.us>
In blinsert(), cope with the possibility that a page we pull from the
notFullPage list is marked BLOOM_DELETED. This could happen if VACUUM
recently marked it deleted but hasn't (yet) updated the metapage.
We can re-use such a page safely, but we *must* reinitialize it so that
it's no longer marked deleted.
Fix blvacuum() so that it updates the notFullPage list even if it's
going to update it to empty. The previous "optimization" of skipping
the update seems pretty dubious, since it means that the next blinsert()
will uselessly visit whatever pages we left in the list.
Uniformly treat PageIsNew pages the same as deleted pages. This should
allow proper recovery if a crash occurs just after relation extension.
Properly use vacuum_delay_point, not assorted ad-hoc CHECK_FOR_INTERRUPTS
calls, in the blvacuum() main loop.
Fix broken tuple-counting logic: blvacuum.c counted the number of live
index tuples over again in each scan, leading to VACUUM VERBOSE reporting
some multiple of the actual number of surviving index tuples after any
vacuum that removed any tuples (since they'd be counted in blvacuum, maybe
more than once, and then again in blvacuumcleanup, without ever zeroing the
counter). It's sufficient to count them in blvacuumcleanup.
stats->estimated_count is a boolean, not a counter, and we don't want
to set it true, so don't add tuple counts to it.
Add a couple of Asserts that we don't overrun available space on a bloom
page. I don't think there's any bug there today, but the way the
FreeBlockNumberArray size calculation is set up is scarily fragile, and
BloomPageGetFreeSpace isn't much better. The Asserts should help catch
any future mistakes.
Per investigation of a report from Jeff Janes. I think the first item
above may explain his report; the other changes were things I noticed
while casting about for an explanation.
Report: <CAMkU=1xEUuBphDwDmB1WjN4+td4kpnEniFaTBxnk1xzHCw8_OQ@mail.gmail.com>
Per discussion, we should provide such functions to replace the lost
ability to discover AM properties by inspecting pg_am (cf commit
65c5fcd35). The added functionality is also meant to displace any code
that was looking directly at pg_index.indoption, since we'd rather not
believe that the bit meanings in that field are part of any client API
contract.
As future-proofing, define the SQL API to not assume that properties that
are currently AM-wide or index-wide will remain so unless they logically
must be; instead, expose them only when inquiring about a specific index
or even specific index column. Also provide the ability for an index
AM to override the behavior.
In passing, document pg_am.amtype, overlooked in commit 473b93287.
Andrew Gierth, with kibitzing by me and others
Discussion: <87mvl5on7n.fsf@news-spur.riddles.org.uk>
This oversight could cause logical decoding to fail to decode an outer
transaction containing changes, if a subtransaction had an XID but no
actual changes. Per bug #14279 from Marko Tiikkaja. Patch by Marko
based on analysis by Andrew Gierth.
Discussion: <20160804191757.1430.39011@wrigleys.postgresql.org>
Commits 4452000f3 et al established semantics for NullTest.argisrow that
are a bit different from its initial conception: rather than being merely
a cache of whether we've determined the input to have composite type,
the flag now has the further meaning that we should apply field-by-field
testing as per the standard's definition of IS [NOT] NULL. If argisrow
is false and yet the input has composite type, the construct instead has
the semantics of IS [NOT] DISTINCT FROM NULL. Update the comments in
primnodes.h to clarify this, and fix ruleutils.c and deparse.c to print
such cases correctly. In the case of ruleutils.c, this merely results in
cosmetic changes in EXPLAIN output, since the case can't currently arise
in stored rules. However, it represents a live bug for deparse.c, which
would formerly have sent a remote query that had semantics different
from the local behavior. (From the user's standpoint, this means that
testing a remote nested-composite column for null-ness could have had
unexpected recursive behavior much like that fixed in 4452000f3.)
In a related but somewhat independent fix, make plancat.c set argisrow
to false in all NullTest expressions constructed to represent "attnotnull"
constructs. Since attnotnull is actually enforced as a simple null-value
check, this is a more accurate representation of the semantics; we were
previously overpromising what it meant for composite columns, which might
possibly lead to incorrect planner optimizations. (It seems that what the
SQL spec expects a NOT NULL constraint to mean is an IS NOT NULL test, so
arguably we are violating the spec and should fix attnotnull to do the
other thing. If we ever do, this part should get reverted.)
Back-patch, same as the previous commit.
Discussion: <10682.1469566308@sss.pgh.pa.us>
That script is incorrect in that it sets the combine function for
max(citext) twice instead of setting the combine function for
max(citext) once and the combine functon for min(citext) once. The
consequence is that if you install 1.0 or 1.1 and then update to 1.2,
you end up with min(citext) not having a combine function, contrary to
what was intended. If you install 1.2 directly, you're OK.
Fix things up by defining a new 1.3 version. Upgrading from 1.2 to
1.3 won't change anything for people who first installed the 1.2
version, but people upgrading from 1.0 or 1.1 will get the right
catalog contents once they reach 1.3.
Report and patch by David Rowley, reviewed by Andreas Karlsson.
In btree_gin and citext, avoid some not-particularly-interesting
dependencies on the sorting of 'aa'. In tsearch2, use COLLATE "C" to
remove an uninteresting dependency on locale sort order (and thereby
allow removal of a variant expected-file).
Also, in citext, avoid assuming that lower('I') = 'i'. This isn't relevant
to Danish but it does fail in Turkish.
To ensure that "make installcheck" can be used safely against an existing
installation, we need to be careful about what global object names
(database, role, and tablespace names) we use; otherwise we might
accidentally clobber important objects. There's been a weak consensus that
test databases should have names including "regression", and that test role
names should start with "regress_", but we didn't have any particular rule
about tablespace names; and neither of the other rules was followed with
any consistency either.
This commit moves us a long way towards having a hard-and-fast rule that
regression test databases must have names including "regression", and that
test role and tablespace names must start with "regress_". It's not
completely there because I did not touch some test cases in rolenames.sql
that test creation of special role names like "session_user". That will
require some rethinking of exactly what we want to test, whereas the intent
of this patch is just to hit all the cases in which the needed renamings
are cosmetic.
There is no enforcement mechanism in this patch either, but if we don't
add one we can expect that the tests will soon be violating the convention
again. Again, that's not such a cosmetic change and it will require
discussion. (But I did use a quick-hack enforcement patch to find these
cases.)
Discussion: <16638.1468620817@sss.pgh.pa.us>
The old code used SEQ_MINVALUE to get the smallest int64 value. This
was done as a convenience to avoid having to deal with INT64_IS_BUSTED,
but that is obsolete now. Also, it is incorrect because the smallest
int64 value is actually SEQ_MINVALUE-1. Fix by using PG_INT64_MIN.
We must not push down a foreign join when the foreign tables involved
should be accessed under different user mappings. Previously we tried
to enforce that rule literally during planning, but that meant that the
resulting plans were dependent on the current contents of the
pg_user_mapping catalog, and we had to blow away all cached plans
containing any remote join when anything at all changed in pg_user_mapping.
This could have been improved somewhat, but the fact that a syscache inval
callback has very limited info about what changed made it hard to do better
within that design. Instead, let's change the planner to not consider user
mappings per se, but to allow a foreign join if both RTEs have the same
checkAsUser value. If they do, then they necessarily will use the same
user mapping at runtime, and we don't need to know specifically which one
that is. Post-plan-time changes in pg_user_mapping no longer require any
plan invalidation.
This rule does give up some optimization ability, to wit where two foreign
table references come from views with different owners or one's from a view
and one's directly in the query, but nonetheless the same user mapping
would have applied. We'll sacrifice the first case, but to not regress
more than we have to in the second case, allow a foreign join involving
both zero and nonzero checkAsUser values if the nonzero one is the same as
the prevailing effective userID. In that case, mark the plan as only
runnable by that userID.
The plancache code already had a notion of plans being userID-specific,
in order to support RLS. It was a little confused though, in particular
lacking clarity of thought as to whether it was the rewritten query or just
the finished plan that's dependent on the userID. Rearrange that code so
that it's clearer what depends on which, and so that the same logic applies
to both RLS-injected role dependency and foreign-join-injected role
dependency.
Note that this patch doesn't remove the other issue mentioned in the
original complaint, which is that while we'll reliably stop using a foreign
join if it's disallowed in a new context, we might fail to start using a
foreign join if it's now allowed, but we previously created a generic
cached plan that didn't use one. It was agreed that the chance of winning
that way was not high enough to justify the much larger number of plan
invalidations that would have to occur if we tried to cause it to happen.
In passing, clean up randomly-varying spelling of EXPLAIN commands in
postgres_fdw.sql, and fix a COSTS ON example that had been allowed to
leak into the committed tests.
This reverts most of commits fbe5a3fb7 and 5d4171d1c, which were the
previous attempt at ensuring we wouldn't push down foreign joins that
span permissions contexts.
Etsuro Fujita and Tom Lane
Discussion: <d49c1e5b-f059-20f4-c132-e9752ee0113e@lab.ntt.co.jp>
This is fallout from join pushdown; get_relid_attribute_name can't
handle an attribute number of 0, indicating a whole-row reference,
and shouldn't be called in that case.
Etsuro Fujita, reviewed by Ashutosh Bapat
As pointed out by Ashutosh Bapat, the header comments for this file
say that schema-qualification is needed for all and only those types
outside pg_catalog. pg_catalog.text is not outside pg_catalog.
After pg_upgrade, it is possible that some tuples' Xmax have multixacts
corresponding to the old installation; such multixacts cannot have
running members anymore. In many code sites we already know not to read
them and clobber them silently, but at least when VACUUM tries to freeze
a multixact or determine whether one needs freezing, there's an attempt
to resolve it to its member transactions by calling GetMultiXactIdMembers,
and if the multixact value is "in the future" with regards to the
current valid multixact range, an error like this is raised:
ERROR: MultiXactId 123 has not been created yet -- apparent wraparound
and vacuuming fails. Per discussion with Andrew Gierth, it is completely
bogus to try to resolve multixacts coming from before a pg_upgrade,
regardless of where they stand with regards to the current valid
multixact range.
It's possible to get from under this problem by doing SELECT FOR UPDATE
of the problem tuples, but if tables are large, this is slow and
tedious, so a more thorough solution is desirable.
To fix, we realize that multixacts in xmax created in 9.2 and previous
have a specific bit pattern that is never used in 9.3 and later (we
already knew this, per comments and infomask tests sprinkled in various
places, but we weren't leveraging this knowledge appropriately).
Whenever the infomask of the tuple matches that bit pattern, we just
ignore the multixact completely as if Xmax wasn't set; or, in the case
of tuple freezing, we act as if an unwanted value is set and clobber it
without decoding. This guarantees that no errors will be raised, and
that the values will be progressively removed until all tables are
clean. Most callers of GetMultiXactIdMembers are patched to recognize
directly that the value is a removable "empty" multixact and avoid
calling GetMultiXactIdMembers altogether.
To avoid changing the signature of GetMultiXactIdMembers() in back
branches, we keep the "allow_old" boolean flag but rename it to
"from_pgupgrade"; if the flag is true, we always return an empty set
instead of looking up the multixact. (I suppose we could remove the
argument in the master branch, but I chose not to do so in this commit).
This was broken all along, but the error-facing message appeared first
because of commit 8e9a16ab8f and was partially fixed in a25c2b7c4d.
This fix, backpatched all the way back to 9.3, goes approximately in the
same direction as a25c2b7c4d but should cover all cases.
Bug analysis by Andrew Gierth and Álvaro Herrera.
A number of public reports match this bug:
https://www.postgresql.org/message-id/20140330040029.GY4582@tamriel.snowman.nethttps://www.postgresql.org/message-id/538F3D70.6080902@publicrelay.comhttps://www.postgresql.org/message-id/556439CF.7070109@pscs.co.ukhttps://www.postgresql.org/message-id/SG2PR06MB0760098A111C88E31BD4D96FB3540@SG2PR06MB0760.apcprd06.prod.outlook.comhttps://www.postgresql.org/message-id/20160615203829.5798.4594@wrigleys.postgresql.org
something.* IS NOT NULL means that every attribute of the row is not
NULL, not that the row itself is non-NULL (e.g. because it's coming
from below an outer join. Use (somevar.*)::pg_catalog.text IS NOT
NULL instead.
Ashutosh Bapat, per a report by Rushabh Lathia. Reviewed by
Amit Langote and Etsuro Fujita. Schema-qualification added by me.
There was some very strange code here, dating to commit b525bf77, that
purported to work around an ancient gcc bug by forcing a float4 comparison
to be done as int instead. Commit 5871b8848 broke that when it changed
one side of the comparison to "double" but left the comparison code alone.
Commit f576b17cd doubled down on the weirdness by introducing a "volatile"
marker, which had nothing to do with the actual problem.
Guess that the gcc bug, even if it's still present in the wild, was
triggered by comparison of float4's and can be avoided if we store the
result of cnt_sml() into a double before comparing to the double "nlimit".
This will at least work correctly on non-broken compilers, and it's way
more readable.
Per bug #14202 from Greg Navis. Add a regression test based on his
example.
Report: <20160620115321.5792.10766@wrigleys.postgresql.org>
As shown by buildfarm reports, dblink_build_sql_insert and
dblink_build_sql_update are *not* parallel safe, because they
may attempt to access temporary tables of the local session.
Although dblink_build_sql_delete doesn't actually touch the
contents of the referenced table, it seems consistent and prudent
to mark it PARALLEL RESTRICTED too.
This requires some core changes as well so that we can properly
WAL-log the truncation. Specifically, it changes the format of the
XLOG_SMGR_TRUNCATE WAL record, so bump XLOG_PAGE_MAGIC.
Patch by me, reviewed but not fully endorsed by Andres Freund.
Almost all functions provided by this extension are PARALLEL
RESTRICTED. Mostly, that's because the leader's TCP connections won't
be shared with the workers, but in some cases like dblink_get_pkey
it's because they obtain locks which might be released early if taken
within a parallel worker. dblink_fdw_validator probably can't be used
in a query anyway, but there would be no problem from the point of
view of parallel query if it were, so it's PARALLEL SAFE.
Andreas Karlsson
The new pg_check_visible() and pg_check_frozen() functions can be used to
verify that the visibility map bits for a relation's data pages match the
actual state of the tuples on those pages.
Amit Kapila and Robert Haas, reviewed (in earlier versions) by Andres
Freund. Additional testing help by Thomas Munro.
All functions provided by this extension are PARALLEL RESTRICTED,
because they provide information about the connection state. Parallel
workers don't have this information and therefore these functions
can't be executed in a worker (but they can be present in a query some
other part of which uses parallelism).
Andreas Karlsson
Commit 749a787c5b bumped the extension
version on all of these extensions already, and we haven't had a
release since then, so we can make further changes without bumping the
extension version again. Take this opportunity to mark all of the
functions exported by these modules PARALLEL SAFE -- except for
pg_trgm's set_limit(). Mark that one PARALLEL RESTRICTED, because it
makes a persistent change to a GUC value.
Note that some of the markings added by this commit don't have any
effect; for example, gseg_picksplit() isn't likely to be mentioned
explicitly in a query and therefore it's parallel-safety marking will
never be consulted. But this commit just marks everything for
consistency: if it were somehow used in a query, that would be fine as
far as parallel query is concerned, since it does not consult any
backend-private state, attempt to write data, etc.
Andreas Karlsson, with a few revisions by me.
As discovered by Andreas Seltenreich via sqlsmith, it's possible for a
remote join to need to generate a target list which contains a
PlaceHolderVar which would need to be evaluated on the remote server.
This happens when we try to push down a join tree which contains outer
joins and the nullable side of the join contains a subquery which
evauates some expression which can go to NULL above the level of the
join. Since the deparsing logic can't build a remote query that
involves subqueries, it fails while trying to produce an SQL query
that can be sent to the remote side. Detect such cases and don't try
to push down the join at all.
It's actually fine to push down the join if the PlaceHolderVar needs
to be evaluated at the current join level. This patch makes a small
change to build_tlist_to_deparse so that this case will work.
Amit Langote, Ashutosh Bapat, and me.
Extension scripts should never use CREATE OR REPLACE for initial object
creation. If there is a collision with a pre-existing (probably
user-created) object, we want extension installation to fail, not silently
overwrite the user's object. Bloom and sslinfo both violated this precept.
Also fix a number of scripts that had no standard header (the file name
comment and the \echo...\quit guard). Probably the \echo...\quit hack
is less important now than it was in 9.1 days, but that doesn't mean
that individual extensions get to choose whether to use it or not.
And fix a couple of evident copy-and-pasteos in file name comments.
No need for back-patch: the REPLACE bugs are both new in 9.6, and the
rest of this is pretty much cosmetic.
Andreas Karlsson and Tom Lane
Andreas Seltenreich reports that it is possible for a PlaceHolderVar
to creep into this tlist, and I fear that even after that's fixed we
might have other, similar bugs in this area either now or in the
future. There's a lot of action-at-a-distance here, because the
validity of this assertion depends on core planner behavior; so, let's
use elog() to make sure we catch this even in non-assert builds,
rather than just crashing.
All functions provided by this extension are PARALLEL SAFE. Given the
general prohibition against write operations in parallel queries, it is
perhaps a bit surprising that pg_stat_statements_reset() is parallel safe.
But since it only modifies shared memory, not the database, it's OK.
Andreas Karlsson
In commits 9ff60273e3 and dbe2328959 I (tgl) fixed the
signatures of a bunch of contrib's GIN and GIST support functions so that
they would pass validation by the recently-added amvalidate functions.
The backend does not actually consult or check those signatures otherwise,
so I figured this was basically cosmetic and did not require an extension
version bump. However, Alexander Korotkov pointed out that that would
leave us in a pretty messy situation if we ever wanted to redefine those
functions later, because there wouldn't be a unique way to name them.
Since we're going to be bumping these extensions' versions anyway for
parallel-query cleanups, let's take care of this now.
Andreas Karlsson, adjusted for more search-path-safety by me
Fix still another bug in commit 35fcb1b3d: it failed to fully initialize
the SortSupport states it introduced to allow the executor to re-check
ORDER BY expressions containing distance operators. That led to a null
pointer dereference if the sortsupport code tried to use ssup_cxt. The
problem only manifests in narrow cases, explaining the lack of previous
field reports. It requires a GiST-indexable distance operator that lacks
SortSupport and is on a pass-by-ref data type, which among core+contrib
seems to be only btree_gist's interval opclass; and it requires the scan
to be done as an IndexScan not an IndexOnlyScan, which explains how
btree_gist's regression test didn't catch it. Per bug #14134 from
Jihyun Yu.
Peter Geoghegan
Report: <20160511154904.2603.43889@wrigleys.postgresql.org>
Per discussion, this is a more understandable and future-proof way of
exposing the setting to users. On-disk, we can still store it in words,
so as to not break on-disk compatibility with beta1.
Along the way, clean up the code associated with Bloom reloptions.
Provide explicit macros for default and maximum lengths rather than
having magic numbers buried in multiple places in the code. Drop
the adjustBloomOptions() code altogether: it was useless in view of
the fact that reloptions.c already performed default-substitution and
range checking for the options. Rename a couple of macros and types
for more clarity.
Discussion: <23767.1464926580@sss.pgh.pa.us>
blbuildempty did not do even approximately the right thing: it tried
to add a metapage to the relation's regular data fork, which already
has one at that point. It should look like the ambuildempty methods
for all the standard index types, ie, initialize a metapage image in
some transient storage and then write it directly to the init fork.
To support that, refactor BloomInitMetapage into two functions.
In passing, fix BloomInitMetapage so it doesn't leave the rd_options
field of the index's relcache entry pointing at transient storage.
I'm not sure this had any visible consequence, since nothing much
else is likely to look at a bloom index's rd_options, but it's
certainly poor practice.
Per bug #14155 from Zhou Digoal.
Report: <20160524144146.22598.42558@wrigleys.postgresql.org>
It's possible to begin and end an indexscan without ever calling
amrescan. contrib/bloom, unlike every other index AM, allocated
its "scan->opaque" storage at amrescan time, and thus would crash
in amendscan if amrescan hadn't been called. We could fix this
by putting in a null-pointer check in blendscan, but I see no very
good reason why contrib/bloom should march to its own drummer in
this respect. Let's move that initialization to blbeginscan
instead. Per report from Jeff Janes.
Commit 3151f16e18 was intended to be
a commit of a patch from Ashutosh Bapat, but instead I mistakenly
committed an earlier version from Michael Paquier (because both
patches were submitted with the same filename, and I confused them).
Michael's patch fixes the crash but doesn't actually implement the
correct test.
Repair the incorrect logic, and also expand the comments considerably
so that this is all more clear.
Ashutosh Bapat and Robert Haas
First, even if we cancel a query, we still have to roll back the
containing transaction; otherwise, the session will be left in a
failed transaction state.
Second, we need to support canceling queries whe aborting a
subtransaction as well as when aborting a toplevel transaction.
Etsuro Fujita, reviewed by Michael Paquier
Buildfarm member skink failed with symptoms suggesting that an
auto-analyze had happened and changed the plan displayed for a
test query. Although this is evidently of low probability,
regression tests that sometimes fail are no fun, so add commands
to force a bitmap scan to be chosen.
These adjustments adjust code and comments in minor ways to prevent
pgindent from mangling them. Among other things, I tried to avoid
situations where pgindent would emit "a +b" instead of "a + b", and I
tried to avoid having it break up inline comments across multiple
lines.
CHECK_PAGE_OFFSET_RANGE() has been unused forever.
CHECK_RELATION_BLOCK_RANGE() has been unused in pgstatindex.c ever since
bt_page_stats() and bt_page_items() functions were moved from pgstattuple
to pageinspect module. It still exists in pageinspect/btreefuncs.c.
Daniel Gustafsson
This reverts commit c8e81afc60.
That turns out to have been based on a faulty diagnosis of why the
VS2015 build was misbehaving. Instead, we need to fix DatumGetBool().
It appears that we can no longer get away with using V0 call convention
for bool-returning functions in newer versions of MSVC. The compiler
seems to generate code that doesn't clear the higher-order bits of the
result register, causing the bool result Datum to often read as "true"
when "false" was intended. This is not very surprising, since the
function thinks it's returning a bool-width result but fmgr_oldstyle
assumes that V0 functions return "char *"; what's surprising is that
that hack worked for so long on so many platforms.
The only functions of this description in core+contrib are in contrib/seg,
which we'd intentionally left mostly in V0 style to serve as a warning
canary if V0 call convention breaks. We could imagine hacking things
so that they're still V0 (we'd have to redeclare the bool-returning
functions as returning some suitably wide integer type, like size_t,
at the C level). But on the whole it seems better to convert 'em to V1.
We can still leave the pointer- and int-returning functions in V0 style,
so that the test coverage isn't gone entirely.
Back-patch to 9.5, since our intention is to support VS2015 in 9.5
and later. There's no SQL-level change in the functions' behavior
so back-patching should be safe enough.
Discussion: <22094.1461273324@sss.pgh.pa.us>
Michael Paquier, adjusted some by me
Revert commit 7cb1db1d95, which represented
a misunderstanding of the problem (if snapmgr.h weren't already included
in bufmgr.h, things wouldn't compile anywhere). Instead install what
I think is the real fix.
This fixes a problem which is not new, but with the advent of direct
foreign table modification in 0bf3ae88af,
it's somewhat more likely to be annoying than previously. So,
arrange for a local query cancelation to propagate to the remote side.
Michael Paquier, reviewed by Etsuro Fujita. Original report by
Thom Brown.
If there's a filter condition on either side of a full outer join,
it is neither correct to attach it to the join's ON clause nor to
throw it into the toplevel WHERE clause. Just don't push down the
join in that case.
To maximize the number of cases where we can still push down full
joins, push inner join conditions into the ON clause at the first
opportunity rather than postponing them to the top-level WHERE
clause. This produces nicer SQL, anyway.
This bug was introduced in e4106b2528.
Ashutosh Bapat, per report from Rajkumar Raghuwanshi.
The reverted changes were intended to force a choice of whether any
newly-added BufferGetPage() calls needed to be accompanied by a
test of the snapshot age, to support the "snapshot too old"
feature. Such an accompanying test is needed in about 7% of the
cases, where the page is being used as part of a scan rather than
positioning for other purposes (such as DML or vacuuming). The
additional effort required for back-patching, and the doubt whether
the intended benefit would really be there, have indicated it is
best just to rely on developers to do the right thing based on
comments and existing usage, as we do with many other conventions.
This change should have little or no effect on generated executable
code.
Motivated by the back-patching pain of Tom Lane and Robert Haas
Previously, querying the xmin column of a single postgres_fdw foreign
table fetched the tuple length, xmax the typmod, and cmin or cmax the
composite type OID of the tuple. However, when you queried several
such tables and the join got shipped to the remote side, these columns
ended up containing the remote values of the corresponding columns.
Both behaviors are rather unprincipled, the former for obvious reasons
and the latter because the remote values of these columns don't have
any local significance; our transaction IDs are in a different space
than those of the remote machine. Clean this up by setting all of
these fields to 0 in both cases. Also fix the handling of tableoid
to be sane.
Robert Haas and Ashutosh Bapat, reviewed by Etsuro Fujita.
When re-reading an update involving both an old tuple and a new tuple from
disk, reorderbuffer.c was careless about whether the new tuple is suitably
aligned for direct access --- in general, it isn't. We'd missed seeing
this in the buildfarm because the contrib/test_decoding tests exercise this
code path only a few times, and by chance all of those cases have old
tuples with length a multiple of 4, which is usually enough to make the
access to the new tuple's t_len safe. For some still-not-entirely-clear
reason, however, Debian's sparc build gets a bus error, as reported by
Christoph Berg; perhaps it's assuming 8-byte alignment of the pointer?
The lack of previous field reports is probably because you need all of
these conditions to trigger a crash: an alignment-picky platform (not
Intel), a transaction large enough to spill to disk, an update within
that xact that changes a primary-key field and has an odd-length old tuple,
and of course logical decoding tracing the transaction.
Avoid the alignment assumption by using memcpy instead of fetching t_len
directly, and add a test case that exposes the crash on picky platforms.
Back-patch to 9.4 where the bug was introduced.
Discussion: <20160413094117.GC21485@msg.credativ.de>
Logical messages, added in 3fe3511d05, during decoding failed to filter
messages emitted in other databases and messages emitted "under" a
replication origin the output plugin isn't interested in.
Add tests to verify that both types of filtering actually work. While
touching message.sql remove hunk obsoleted by d25379e.
Bump XLOG_PAGE_MAGIC because xl_logical_message changed and because
3fe3511d05 had omitted doing so. 3fe3511d05 additionally didn't bump
catversion, but 7a542700d has done so since.
Author: Petr Jelinek
Reported-By: Andres Freund
Discussion: 20160406142513.wotqy3ba3kanr423@alap3.anarazel.de
Rename this function to GenericXLogRegisterBuffer() to make it clearer
what it does, and leave room for other sorts of "register" actions in
future. Also, replace its "bool isNew" argument with an integer flags
argument, so as to allow adding more flags in future without an API
break.
Alexander Korotkov, adjusted slightly by me
Added to ensure that bloom index pages can be distinguished from other pages
by pg_filedump. Because there wasn't any public/production versions before,
it doesn't pay attention to any compatibility issues.
Per notice from Tom Lane
Pinning/Unpinning a buffer is a very frequent operation; especially in
read-mostly cache resident workloads. Benchmarking shows that in various
scenarios the spinlock protecting a buffer header's state becomes a
significant bottleneck. The problem can be reproduced with pgbench -S on
larger machines, but can be considerably worse for queries which touch
the same buffers over and over at a high frequency (e.g. nested loops
over a small inner table).
To allow atomic operations to be used, cram BufferDesc's flags,
usage_count, buf_hdr_lock, refcount into a single 32bit atomic variable;
that allows to manipulate them together using 32bit compare-and-swap
operations. This requires reducing MAX_BACKENDS to 2^18-1 (which could
be lifted by using a 64bit field, but it's not a realistic configuration
atm).
As not all operations can easily implemented in a lockfree manner,
implement the previous buf_hdr_lock via a flag bit in the atomic
variable. That way we can continue to lock the header in places where
it's needed, but can get away without acquiring it in the more frequent
hot-paths. There's some additional operations which can be done without
the lock, but aren't in this patch; but the most important places are
covered.
As bufmgr.c now essentially re-implements spinlocks, abstract the delay
logic from s_lock.c into something more generic. It now has already two
users, and more are coming up; there's a follupw patch for lwlock.c at
least.
This patch is based on a proof-of-concept written by me, which Alexander
Korotkov made into a fully working patch; the committed version is again
revised by me. Benchmarking and testing has, amongst others, been
provided by Dilip Kumar, Alexander Korotkov, Robert Haas.
On a large x86 system improvements for readonly pgbench, with a high
client count, of a factor of 8 have been observed.
Author: Alexander Korotkov and Andres Freund
Discussion: 2400449.GjM57CE0Yg@dinodell
Originally, this test created a 100000-row test table, which made it
run rather slowly compared to other contrib tests. Investigation with
gcov showed that we got no further improvement in code coverage after
the first 700 or so rows, making the large table 99% a waste of time.
Cut it back to 2000 rows to fix the runtime problem and still leave
some headroom for testing behaviors that may appear later.
A closer look at the gcov results showed that the main coverage
omissions in contrib/bloom occurred because the test never filled more
than one entry in the notFullPage array; which is unsurprising because
it exercised index cleanup only in the scenario of complete table
deletion, allowing every page in the index to become deleted rather
than not-full. Add testing that allows the not-full path to be
exercised as well.
Also, test the amvalidate function, because blvalidate.c had zero
coverage without that, and besides it's a good idea to check for
mistakes in the bloom opclass definitions.
That routine is dangerous, and unnecessary once we get rid of this
one caller.
In passing, fix failure to clean up temp memory context, or switch
back to caller's context, during slowest exit path.
This feature is controlled by a new old_snapshot_threshold GUC. A
value of -1 disables the feature, and that is the default. The
value of 0 is just intended for testing. Above that it is the
number of minutes a snapshot can reach before pruning and vacuum
are allowed to remove dead tuples which the snapshot would
otherwise protect. The xmin associated with a transaction ID does
still protect dead tuples. A connection which is using an "old"
snapshot does not get an error unless it accesses a page modified
recently enough that it might not be able to produce accurate
results.
This is similar to the Oracle feature, and we use the same SQLSTATE
and error message for compatibility.
This patch is a no-op patch which is intended to reduce the chances
of failures of omission once the functional part of the "snapshot
too old" patch goes in. It adds parameters for snapshot, relation,
and an enum to specify whether the snapshot age check needs to be
done for the page at this point. This initial patch passes NULL
for the first two new parameters and BGP_NO_SNAPSHOT_TEST for the
third. The follow-on patch will change the places where the test
needs to be made.
Now indexes (but only B-tree for now) can contain "extra" column(s) which
doesn't participate in index structure, they are just stored in leaf
tuples. It allows to use index only scan by using single index instead
of two or more indexes.
Author: Anastasia Lubennikova with minor editorializing by me
Reviewers: David Rowley, Peter Geoghegan, Jeff Janes