Commit Graph

3254 Commits

Author SHA1 Message Date
Peter Eisentraut 332bec1e60 postgres_fdw: Fix join push down with extensions
Objects in an extension are shippable to a foreign server if the
extension is part of the foreign server definition's shippable
extensions list.  But this was not properly considered in some cases
when checking whether a join condition can be pushed to a foreign server
and the join condition uses an object from a shippable extension.  So
the join would never be pushed down in those cases.

So, the list of extensions needs to be made available in fpinfo of the
relation being considered to be pushed down before any expressions are
assessed for being shippable.  Fix foreign_join_ok() to do that for a
join relation.

The code to save FDW options in fpinfo is scattered at multiple places.
Bring all of that together into functions apply_server_options(),
apply_table_options(), and merge_fdw_options().

David Rowley and Ashutosh Bapat, per report from David Rowley
2017-04-24 22:50:07 -04:00
Peter Eisentraut 6275f5d28a Fix new warnings from GCC 7
This addresses the new warning types -Wformat-truncation
-Wformat-overflow that are part of -Wall, via -Wformat, in GCC 7.
2017-04-17 13:59:46 -04:00
Tom Lane 2040bb4a0b Clean up manipulations of hash indexes' hasho_flag field.
Standardize on testing a hash index page's type by doing
	(opaque->hasho_flag & LH_PAGE_TYPE) == LH_xxx_PAGE
Various places were taking shortcuts like
	opaque->hasho_flag & LH_BUCKET_PAGE
which while not actually wrong, is still bad practice because
it encourages use of
	opaque->hasho_flag & LH_UNUSED_PAGE
which *is* wrong (LH_UNUSED_PAGE == 0, so the above is constant false).
hash_xlog.c's hash_mask() contained such an incorrect test.

This also ensures that we mask out the additional flag bits that
hasho_flag has accreted since 9.6.  pgstattuple's pgstat_hash_page(),
for one, was failing to do that and was thus actively broken.

Also fix assorted comments that hadn't been updated to reflect the
extended usage of hasho_flag, and fix some macros that were testing
just "(hasho_flag & bit)" to use the less dangerous, project-approved
form "((hasho_flag & bit) != 0)".

Coverity found the bug in hash_mask(); I noted the one in
pgstat_hash_page() through code reading.
2017-04-14 17:04:25 -04:00
Tom Lane 1dffabed49 Further fix pg_trgm's extraction of trigrams from regular expressions.
Commit 9e43e8714 turns out to have been insufficient: not only is it
necessary to track tentative parent links while considering a set of
arc removals, but it's necessary to track tentative flag additions
as well.  This is because we always merge arc target states into
arc source states; therefore, when considering a merge of the final
state with some other, it is the other state that will acquire a new
TSTATE_FIN bit.  If there's another arc for the same color trigram
that would cause merging of that state with the initial state, we
failed to recognize the problem.  The test cases for the prior commit
evidently only exercised situations where a tentative merge with the
initial state occurs before one with the final state.  If it goes the
other way around, we'll happily merge the initial and final states,
either producing a broken final graph that would never match anything,
or triggering the Assert added by the prior commit.

It's tempting to consider switching the merge direction when the merge
involves the final state, but I lack the time to analyze that idea in
detail.  Instead just keep track of the flag changes that would result
from proposed merges, in the same way that the prior commit tracked
proposed parent links.

Along the way, add some more debugging support, because I'm not entirely
confident that this is the last bug here.  And tweak matters so that
the transformed.dot file uses small integers rather than pointer values
to identify states; that makes it more readable if you're just eyeballing
it rather than fooling with Graphviz.  And rename a couple of identically
named struct fields to reduce confusion.

Per report from Corey Csuhta.  Add a test case based on his example.
(Note: this case does not trigger the bug under 9.3, apparently because
its different measurement of costs causes it to stop merging states before
it hits the failure.  I spent some time trying to find a variant that would
fail in 9.3, without success; but I'm sure such cases exist.)

Like the previous patch, back-patch to 9.3 where this code was added.

Report: https://postgr.es/m/E2B01A4B-4530-406B-8D17-2F67CF9A16BA@csuhta.com
2017-04-14 14:52:21 -04:00
Peter Eisentraut 0c22327f26 Remove useless trailing spaces in queries in C strings
Author: Alexander Law <exclusion@gmail.com>
2017-04-13 23:47:46 -04:00
Tom Lane 6cfaffc0dd Fix regexport.c to behave sanely with lookaround constraints.
regexport.c thought it could just ignore LACON arcs, but the correct
behavior is to treat them as satisfiable while consuming zero input
(rather reminiscently of commit 9f1e642d5).  Otherwise, the emitted
simplified-NFA representation may contain no paths leading from initial
to final state, which unsurprisingly confuses pg_trgm, as seen in
bug #14623 from Jeff Janes.

Since regexport's output representation has no concept of an arc that
consumes zero input, recurse internally to find the next normal arc(s)
after any LACON transitions.  We'd be forced into changing that
representation if a LACON could be the last arc reaching the final
state, but fortunately the regex library never builds NFAs with such
a configuration, so there always is a next normal arc.

Back-patch to 9.3 where this logic was introduced.

Discussion: https://postgr.es/m/20170413180503.25948.94871@wrigleys.postgresql.org
2017-04-13 17:18:35 -04:00
Robert Haas 9cc27566c1 Fix pgstattuple's handling of unused hash pages.
Hash indexes can contain both pages which are all-zeroes (i.e.
PageIsNew()) and pages which have been initialized but currently
aren't used.  The latter category can happen either when a page
has been reserved but not yet used or when it is used for a time
and then freed.  pgstattuple was only prepared to deal with the
pages that are actually-zeroes, which it called zero_pages.
Rename the column to unused_pages (extension version 1.5 is
as-yet-unreleased) and make it count both kinds of unused pages.

Along the way, slightly tidy up the way we test for pages of
various types.

Robert Haas and Ashutosh Sharma, reviewed by Amit Kapila

Discussion: http://postgr.es/m/CAE9k0PkTtKFB3YndOyQMjwuHx+-FtUP1ynK8E-nHtetoow3NtQ@mail.gmail.com
2017-04-12 11:53:00 -04:00
Tom Lane 88e902b769 Simplify handling of remote-qual pass-forward in postgres_fdw.
Commit 0bf3ae88a encountered a need to pass the finally chosen remote qual
conditions forward from postgresGetForeignPlan to postgresPlanDirectModify.
It solved that by sticking them into the plan node's fdw_private list,
which in hindsight was a pretty bad idea.  In the first place, there's no
use for those qual trees either in EXPLAIN or execution; indeed they could
never safely be used for any post-planning purposes, because they would not
get processed by setrefs.c.  So they're just dead weight to carry around in
the finished plan tree, plus being an attractive nuisance for somebody who
might get the idea that they could be used that way.  Secondly, because
those qual trees (sometimes) contained RestrictInfos, they created a
plan-transmission hazard for parallel query, which is how come we noticed a
problem.  We dealt with that symptom in commit 28b047875, but really a more
straightforward and more efficient fix is to pass the data through in a new
field of struct PgFdwRelationInfo.  So do it that way.  (There's no need
to revert 28b047875, as it has sufficient reason to live anyway.)

Per fuzz testing by Andreas Seltenreich.

Discussion: https://postgr.es/m/87tw5x4vcu.fsf@credativ.de
2017-04-11 13:53:21 -04:00
Tom Lane 28b0478755 Handle restriction clause lists more uniformly in postgres_fdw.
Clauses in the lists retained by postgres_fdw during planning were
sometimes bare boolean clauses, sometimes RestrictInfos, and sometimes
a mixture of the two in the same list.  The comment about that situation
didn't come close to telling the full truth, either.  Aside from being
confusing, this had a couple of bad practical consequences:
* waste of planning cycles due to inability to cache per-clause selectivity
and cost estimates;
* sometimes, RestrictInfos would sneak into the fdw_private list of a
finished Plan node, causing failures if, for example, we tried to ship
the Plan tree to a parallel worker.
(It may well be that it's a bug in the parallel-query logic that we
would ever try to ship such a plan to a parallel worker, but in any
case this deserves to be cleaned up.)

To fix, rearrange so that clause lists in PgFdwRelationInfo are always
lists of RestrictInfos, and then strip the RestrictInfos at the last
minute when making a Plan node.  In passing do a bit of refactoring and
comment cleanup in postgresGetForeignPlan and foreign_join_ok.

Although the messiness here dates back at least to 9.6, there's no evidence
that it causes anything worse than wasted planning cycles in 9.6, so no
back-patch for now.

Per fuzz testing by Andreas Seltenreich.

Tom Lane and Ashutosh Bapat

Discussion: https://postgr.es/m/87tw5x4vcu.fsf@credativ.de
2017-04-11 11:59:09 -04:00
Tom Lane 8f0530f580 Improve castNode notation by introducing list-extraction-specific variants.
This extends the castNode() notation introduced by commit 5bcab1114 to
provide, in one step, extraction of a list cell's pointer and coercion to
a concrete node type.  For example, "lfirst_node(Foo, lc)" is the same
as "castNode(Foo, lfirst(lc))".  Almost half of the uses of castNode
that have appeared so far include a list extraction call, so this is
pretty widely useful, and it saves a few more keystrokes compared to the
old way.

As with the previous patch, back-patch the addition of these macros to
pg_list.h, so that the notation will be available when back-patching.

Patch by me, after an idea of Andrew Gierth's.

Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us
2017-04-10 13:51:53 -04:00
Peter Eisentraut 244f1c8907 Fix whitespace 2017-04-10 11:18:15 -04:00
Joe Conway 86fa9b2d1b Make sepgsql regression tests robust vs. collation differences
In commit 25542d77, regression test coverage was added to sepgsql
for partitioned tables. Unfortunately it was not robust in the face
of collation differences, per the buildfarm. Force "C" collation
in order to fix that.

Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
2017-04-09 15:59:02 -07:00
Joe Conway 25542d77dd Add partitioned table support to sepgsql
The new partitioned table capability added a new relkind, namely
RELKIND_PARTITIONED_TABLE. Update sepgsql to treat this new relkind
exactly the same way it does RELKIND_RELATION.

In addition, add regression test coverage for partitioned tables.

Issue raised by Stephen Frost and initial patch by Mike Palmiotto.
Review by Tom Lane and Robert Haas, and editorializing by me.

Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
2017-04-09 14:01:58 -07:00
Tom Lane 9c7f5229ad Optimize joins when the inner relation can be proven unique.
If there can certainly be no more than one matching inner row for a given
outer row, then the executor can move on to the next outer row as soon as
it's found one match; there's no need to continue scanning the inner
relation for this outer row.  This saves useless scanning in nestloop
and hash joins.  In merge joins, it offers the opportunity to skip
mark/restore processing, because we know we have not advanced past the
first possible match for the next outer row.

Of course, the devil is in the details: the proof of uniqueness must
depend only on joinquals (not otherquals), and if we want to skip
mergejoin mark/restore then it must depend only on merge clauses.
To avoid adding more planning overhead than absolutely necessary,
the present patch errs in the conservative direction: there are cases
where inner_unique or skip_mark_restore processing could be used, but
it will not do so because it's not sure that the uniqueness proof
depended only on "safe" clauses.  This could be improved later.

David Rowley, reviewed and rather heavily editorialized on by me

Discussion: https://postgr.es/m/CAApHDvqF6Sw-TK98bW48TdtFJ+3a7D2mFyZ7++=D-RyPsL76gw@mail.gmail.com
2017-04-07 22:20:13 -04:00
Alvaro Herrera 8bf74967da Reduce the number of pallocs() in BRIN
Instead of allocating memory in brin_deform_tuple and brin_copy_tuple
over and over during a scan, allow reuse of previously allocated memory.
This is said to make for a measurable performance improvement.

Author: Jinyu Zhang, Álvaro Herrera
Reviewed by: Tomas Vondra
Discussion: https://postgr.es/m/495deb78.4186.1500dacaa63.Coremail.beijing_pg@163.com
2017-04-07 19:08:43 -03:00
Simon Riggs ac2b095088 Reset API of clause_selectivity()
Discussion: https://postgr.es/m/CAKJS1f9yurJQW9pdnzL+rmOtsp2vOytkpXKGnMFJEO-qz5O5eA@mail.gmail.com
2017-04-06 19:10:51 -04:00
Joe Conway af8a94d18d Silence uninitialized variable compiler warning in sepgsql
At -Og optimization gcc warns that variable tclass may be used
uninitialized when relkind == RELKIND_INDEX. Actually that can't
happen due to an early return, but quiet the compiler by initializing
tclass to 0.

In passing, use uint16_t consistently for the declaration of tclass.

Complaint and initial patch by Mike Palmiotto. Editorializing by me.
Probably not worth backpatching given that it is cosmetic, so apply
to development head only.

Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
2017-04-06 14:28:19 -07:00
Joe Conway bd190eae36 Silence compiler warning in sepgsql
<selinux/label.h> includes <stdbool.h>, which creates an incompatible
We don't care if <stdbool.h> redefines "true"/"false"; those are close
enough.

Complaint and initial patch by Mike Palmiotto. Final approach per
Tom Lane's suggestion, as discussed on hackers. Backpatching to
all supported branches.

Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
2017-04-06 14:24:29 -07:00
Peter Eisentraut 301ca0d9a2 Fix AclResult vs bool type mix-up
Using AclResult as a bool or vice versa works by accident, but it's
unusual and possibly confusing style, so write it out more explicitly.
2017-04-06 11:32:07 -04:00
Simon Riggs 2686ee1b7c Collect and use multi-column dependency stats
Follow on patch in the multi-variate statistics patch series.

CREATE STATISTICS s1 WITH (dependencies) ON (a, b) FROM t;
ANALYZE;
will collect dependency stats on (a, b) and then use the measured
dependency in subsequent query planning.

Commit 7b504eb282 added
CREATE STATISTICS with n-distinct coefficients. These are now
specified using the mutually exclusive option WITH (ndistinct).

Author: Tomas Vondra, David Rowley
Reviewed-by: Kyotaro HORIGUCHI, Álvaro Herrera, Dean Rasheed, Robert Haas
and many other comments and contributions
Discussion: https://postgr.es/m/56f40b20-c464-fad2-ff39-06b668fac47c@2ndquadrant.com
2017-04-05 18:00:42 -04:00
Robert Haas 633e15ea0f Fix pageinspect failures on hash indexes.
Make every page in a hash index which isn't all-zeroes have a valid
special space, so that tools like pageinspect don't error out.

Also, make pageinspect cope with all-zeroes pages, because
_hash_alloc_buckets can leave behind large numbers of those until
they're consumed by splits.

Ashutosh Sharma and Robert Haas, reviewed by Amit Kapila.
Original trouble report from Jeff Janes.

Discussion: http://postgr.es/m/CAMkU=1y6NjKmqbJ8wLMhr=F74WzcMALYWcVFhEpm7i=mV=XsOg@mail.gmail.com
2017-04-05 14:18:15 -04:00
Peter Eisentraut e59b74a3fc dblink: Small code rearrangement for clarity
suggested by Tom Lane
2017-04-05 09:03:11 -04:00
Peter Eisentraut afd79873a0 Capitalize names of PLs consistently
Author: Daniel Gustafsson <daniel@yesql.se>
2017-04-05 00:38:25 -04:00
Peter Eisentraut 193f5f9e91 pageinspect: Add bt_page_items function with bytea argument
Author: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Reviewed-by: Ashutosh Sharma <ashu.coek88@gmail.com>
2017-04-04 23:52:55 -04:00
Andres Freund bae9b80160 Force synchronous commit in new-ish test_decoding test.
This was missed in a924c327 ff.
2017-04-04 14:38:00 -07:00
Robert Haas ea69a0dead Expand hash indexes more gradually.
Since hash indexes typically have very few overflow pages, adding a
new splitpoint essentially doubles the on-disk size of the index,
which can lead to large and abrupt increases in disk usage (and
perhaps long delays on occasion).  To mitigate this problem to some
degree, divide larger splitpoints into four equal phases.  This means
that, for example, instead of growing from 4GB to 8GB all at once, a
hash index will now grow from 4GB to 5GB to 6GB to 7GB to 8GB, which
is perhaps still not as smooth as we'd like but certainly an
improvement.

This changes the on-disk format of the metapage, so bump HASH_VERSION
from 2 to 3.  This will force a REINDEX of all existing hash indexes,
but that's probably a good idea anyway.  First, hash indexes from
pre-10 versions of PostgreSQL could easily be corrupted, and we don't
want to confuse corruption carried over from an older release with any
corruption caused despite the new write-ahead logging in v10.  Second,
it will let us remove some backward-compatibility code added by commit
293e24e507.

Mithun Cy, reviewed by Amit Kapila, Jesper Pedersen and me.  Regression
test outputs updated by me.

Discussion: http://postgr.es/m/CAD__OuhG6F1gQLCgMQNnMNgoCvOLQZz9zKYJQNYvYmmJoM42gA@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoYty0jCf-pa+m+vYUJ716+AxM7nv_syvyanyf5O-L_i2A@mail.gmail.com
2017-04-03 23:46:33 -04:00
Robert Haas 7a39b5e4d1 Abstract logic to allow for multiple kinds of child rels.
Currently, the only type of child relation is an "other member rel",
which is the child of a baserel, but in the future joins and even
upper relations may have child rels.  To facilitate that, introduce
macros that test to test for particular RelOptKind values, and use
them in various places where they help to clarify the sense of a test.
(For example, a test may allow RELOPT_OTHER_MEMBER_REL either because
it intends to allow child rels, or because it intends to allow simple
rels.)

Also, remove find_childrel_top_parent, which will not work for a
child rel that is not a baserel.  Instead, add a new RelOptInfo
member top_parent_relids to track the same kind of information in a
more generic manner.

Ashutosh Bapat, slightly tweaked by me.  Review and testing of the
patch set from which this was taken by Rajkumar Raghuwanshi and Rafia
Sabih.

Discussion: http://postgr.es/m/CA+TgmoagTnF2yqR3PT2rv=om=wJiZ4-A+ATwdnriTGku1CLYxA@mail.gmail.com
2017-04-03 22:41:31 -04:00
Kevin Grittner 01fd6f8f2d Try to fix breakage of sepgsql hooks by ENR patch.
Turned up by buildfarm animal rhinoceros.  Fixing blind.  Will have
to wait for next run by rhinoceros to know whether it worked.
2017-04-01 00:10:12 -05:00
Kevin Grittner 18ce3a4ab2 Add infrastructure to support EphemeralNamedRelation references.
A QueryEnvironment concept is added, which allows new types of
objects to be passed into queries from parsing on through
execution.  At this point, the only thing implemented is a
collection of EphemeralNamedRelation objects -- relations which
can be referenced by name in queries, but do not exist in the
catalogs.  The only type of ENR implemented is NamedTuplestore, but
provision is made to add more types fairly easily.

An ENR can carry its own TupleDesc or reference a relation in the
catalogs by relid.

Although these features can be used without SPI, convenience
functions are added to SPI so that ENRs can easily be used by code
run through SPI.

The initial use of all this is going to be transition tables in
AFTER triggers, but that will be added to each PL as a separate
commit.

An incidental effect of this patch is to produce a more informative
error message if an attempt is made to modify the contents of a CTE
from a referencing DML statement.  No tests previously covered that
possibility, so one is added.

Kevin Grittner and Thomas Munro
Reviewed by Heikki Linnakangas, David Fetter, and Thomas Munro
with valuable comments and suggestions from many others
2017-03-31 23:17:18 -05:00
Robert Haas f49bcd4ef3 postgres_fdw: Teach IMPORT FOREIGN SCHEMA about partitioning.
Don't import partitions.  Do import partitioned tables which are
not themselves partitions.

Report by Stephen Frost.  Design and patch by Michael Paquier,
reviewed by Amit Langote.  Documentation revised by me.

Discussion: http://postgr.es/m/20170309141531.GD9812@tamriel.snowman.net
2017-03-31 15:06:34 -04:00
Simon Riggs ceb3158abe Fix pgrowlocks minor coding oversight 2017-03-30 14:53:07 -04:00
Simon Riggs 25fff40798 Default monitoring roles
Three nologin roles with non-overlapping privs are created by default
* pg_read_all_settings - read all GUCs.
* pg_read_all_stats - pg_stat_*, pg_database_size(), pg_tablespace_size()
* pg_stat_scan_tables - may lock/scan tables

Top level role - pg_monitor includes all of the above by default, plus others

Author: Dave Page
Reviewed-by: Stephen Frost, Robert Haas, Peter Eisentraut, Simon Riggs
2017-03-30 14:18:53 -04:00
Andres Freund 5ded4bd214 Remove support for version-0 calling conventions.
The V0 convention is failure prone because we've so far assumed that a
function is V0 if PG_FUNCTION_INFO_V1 is missing, leading to crashes
if a function was coded against the V1 interface.  V0 doesn't allow
proper NULL, SRF and toast handling.  V0 doesn't offer features that
V1 doesn't.

Thus remove V0 support and obsolete fmgr README contents relating to
it.

Author: Andres Freund, with contributions by Peter Eisentraut & Craig Ringer
Reviewed-By: Peter Eisentraut, Craig Ringer
Discussion: https://postgr.es/m/20161208213441.k3mbno4twhg2qf7g@alap3.anarazel.de
2017-03-30 06:25:46 -07:00
Andres Freund 389bb2818f Move contrib/seg to only use V1 calling conventions.
A later commit will remove V0 support.

Author: Andres Freund, with contributions by Craig Ringer
Reviewed-By: Peter Eisentraut, Craig Ringer
Discussion: https://postgr.es/m/20161208213441.k3mbno4twhg2qf7g@alap3.anarazel.de
2017-03-30 06:25:46 -07:00
Alvaro Herrera ce96ce60ca Remove direct uses of ItemPointer.{ip_blkid,ip_posid}
There are no functional changes here; this simply encapsulates knowledge
of the ItemPointerData struct so that a future patch can change things
without more breakage.

All direct users of ip_blkid and ip_posid are changed to use existing
macros ItemPointerGetBlockNumber and ItemPointerGetOffsetNumber
respectively.  For callers where that's inappropriate (because they
Assert that the itempointer is is valid-looking), add
ItemPointerGetBlockNumberNoCheck and ItemPointerGetOffsetNumberNoCheck,
which lack the assertion but are otherwise identical.

Author: Pavan Deolasee
Discussion: https://postgr.es/m/CABOikdNnFon4cJiL=h1mZH3bgUeU+sWHuU4Yr8AB=j3A2p1GiA@mail.gmail.com
2017-03-28 19:02:23 -03:00
Peter Eisentraut 85163641f8 dblink: Fix error reporting
The conname variable was not initialized in some code paths, resulting
in error reports referring to the "unnamed" connection rather than the
correct connection name.

Author: Rushabh Lathia <rushabh.lathia@gmail.com>
2017-03-28 11:08:38 -04:00
Tom Lane a6f22e8356 Show ignored constants as "$N" rather than "?" in pg_stat_statements.
The trouble with the original choice here is that "?" is a valid (and
indeed used) operator name, so that you could end up with ambiguous
statement texts like "SELECT ? ? ?".  With this patch, you instead
see "SELECT $1 ? $2", which seems significantly more readable.
The numbers used for this purpose begin after the last actual $N parameter
in the particular query.  The conflict with external parameters has its own
potential for confusion of course, but it was agreed to be an improvement
over the previous behavior.

Lukas Fittl

Discussion: https://postgr.es/m/CAP53PkxeaCuwYmF-A4J5z2-qk5fYFo5_NH3gpXGJJBxv1DMwEw@mail.gmail.com
2017-03-27 20:14:36 -04:00
Peter Eisentraut facde2a98f Clean up Perl code according to perlcritic
Fix all perlcritic warnings of severity level 5, except in
src/backend/utils/Gen_dummy_probes.pl, which is automatically generated.

Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
2017-03-27 08:18:22 -04:00
Andrew Gierth b5635948ab Support hashed aggregation with grouping sets.
This extends the Aggregate node with two new features: HashAggregate
can now run multiple hashtables concurrently, and a new strategy
MixedAggregate populates hashtables while doing sorted grouping.

The planner will now attempt to save as many sorts as possible when
planning grouping sets queries, while not exceeding work_mem for the
estimated combined sizes of all hashtables used.  No SQL-level changes
are required.  There should be no user-visible impact other than the
new EXPLAIN output and possible changes to result ordering when ORDER
BY was not used (which affected a few regression tests).  The
enable_hashagg option is respected.

Author: Andrew Gierth
Reviewers: Mark Dilger, Andres Freund
Discussion: https://postgr.es/m/87vatszyhj.fsf@news-spur.riddles.org.uk
2017-03-27 04:20:54 +01:00
Andres Freund d253b0f6e3 Blindly attempt to fix sepgsql tests #2. 2017-03-25 20:54:23 -07:00
Andres Freund 83bbcb04ab Blindly attempt to fix sepgsql tests.
Due to b8d7f053c5 some permission checks are now happening even on
empty tables, and some of the checks move around.

Discussion: https://postgr.es/m/95bdb608-093c-160f-c6be-983a36ccd7f9@joeconway.com
2017-03-25 20:35:55 -07:00
Andres Freund b8d7f053c5 Faster expression evaluation and targetlist projection.
This replaces the old, recursive tree-walk based evaluation, with
non-recursive, opcode dispatch based, expression evaluation.
Projection is now implemented as part of expression evaluation.

This both leads to significant performance improvements, and makes
future just-in-time compilation of expressions easier.

The speed gains primarily come from:
- non-recursive implementation reduces stack usage / overhead
- simple sub-expressions are implemented with a single jump, without
  function calls
- sharing some state between different sub-expressions
- reduced amount of indirect/hard to predict memory accesses by laying
  out operation metadata sequentially; including the avoidance of
  nearly all of the previously used linked lists
- more code has been moved to expression initialization, avoiding
  constant re-checks at evaluation time

Future just-in-time compilation (JIT) has become easier, as
demonstrated by released patches intended to be merged in a later
release, for primarily two reasons: Firstly, due to a stricter split
between expression initialization and evaluation, less code has to be
handled by the JIT. Secondly, due to the non-recursive nature of the
generated "instructions", less performance-critical code-paths can
easily be shared between interpreted and compiled evaluation.

The new framework allows for significant future optimizations. E.g.:
- basic infrastructure for to later reduce the per executor-startup
  overhead of expression evaluation, by caching state in prepared
  statements.  That'd be helpful in OLTPish scenarios where
  initialization overhead is measurable.
- optimizing the generated "code". A number of proposals for potential
  work has already been made.
- optimizing the interpreter. Similarly a number of proposals have
  been made here too.

The move of logic into the expression initialization step leads to some
backward-incompatible changes:
- Function permission checks are now done during expression
  initialization, whereas previously they were done during
  execution. In edge cases this can lead to errors being raised that
  previously wouldn't have been, e.g. a NULL array being coerced to a
  different array type previously didn't perform checks.
- The set of domain constraints to be checked, is now evaluated once
  during expression initialization, previously it was re-built
  every time a domain check was evaluated. For normal queries this
  doesn't change much, but e.g. for plpgsql functions, which caches
  ExprStates, the old set could stick around longer.  The behavior
  around might still change.

Author: Andres Freund, with significant changes by Tom Lane,
	changes by Heikki Linnakangas
Reviewed-By: Tom Lane, Heikki Linnakangas
Discussion: https://postgr.es/m/20161206034955.bh33paeralxbtluv@alap3.anarazel.de
2017-03-25 14:52:06 -07:00
Robert Haas 691b8d5928 Allow for parallel execution whenever ExecutorRun() is done only once.
Previously, it was unsafe to execute a plan in parallel if
ExecutorRun() might be called with a non-zero row count.  However,
it's quite easy to fix things up so that we can support that case,
provided that it is known that we will never call ExecutorRun() a
second time for the same QueryDesc.  Add infrastructure to signal
this, and cross-checks to make sure that a caller who claims this is
true doesn't later reneg.

While that pattern never happens with queries received directly from a
client -- there's no way to know whether multiple Execute messages
will be sent unless the first one requests all the rows -- it's pretty
common for queries originating from procedural languages, which often
limit the result to a single tuple or to a user-specified number of
tuples.

This commit doesn't actually enable parallelism in any additional
cases, because currently none of the places that would be able to
benefit from this infrastructure pass CURSOR_OPT_PARALLEL_OK in the
first place, but it makes it much more palatable to pass
CURSOR_OPT_PARALLEL_OK in places where we currently don't, because it
eliminates some cases where we'd end up having to run the parallel
plan serially.

Patch by me, based on some ideas from Rafia Sabih and corrected by
Rafia Sabih based on feedback from Dilip Kumar and myself.

Discussion: http://postgr.es/m/CA+TgmobXEhvHbJtWDuPZM9bVSLiTj-kShxQJ2uM5GPDze9fRYA@mail.gmail.com
2017-03-23 13:14:36 -04:00
Peter Eisentraut 7c4f52409a Logical replication support for initial data copy
Add functionality for a new subscription to copy the initial data in the
tables and then sync with the ongoing apply process.

For the copying, add a new internal COPY option to have the COPY source
data provided by a callback function.  The initial data copy works on
the subscriber by receiving COPY data from the publisher and then
providing it locally into a COPY that writes to the destination table.

A WAL receiver can now execute full SQL commands.  This is used here to
obtain information about tables and publications.

Several new options were added to CREATE and ALTER SUBSCRIPTION to
control whether and when initial table syncing happens.

Change pg_dump option --no-create-subscription-slots to
--no-subscription-connect and use the new CREATE SUBSCRIPTION
... NOCONNECT option for that.

Author: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Tested-by: Erik Rijkers <er@xs4all.nl>
2017-03-23 08:55:37 -04:00
Simon Riggs af4b1a0869 Refactor GetOldestXmin() to use flags
Replace ignoreVacuum parameter with more flexible flags.

Author: Eiji Seki
Review: Haribabu Kommi
2017-03-22 16:51:01 +00:00
Andrew Dunstan 4ad0f88c44 Add btree_gin support for enum types
Reviewed by Tom Lane and Anastasia Lubennikova

Discussion:  http://postgr.es/m/56EA8A71.8060107@dunslane.net
2017-03-21 11:04:17 -04:00
Andrew Dunstan f7946a92b6 Add btree_gist support for enum types.
This will allow enums to be used in exclusion constraints.

The code uses the new CallerFInfoFunctionCall infrastructure in fmgr,
and the support for it added to btree_gist in commit 393bb504d7.

Reviewed by Tom Lane and Anastasia Lubennikova

Discussion:  http://postgr.es/m/56EA8A71.8060107@dunslane.net
2017-03-21 10:43:27 -04:00
Andrew Dunstan 65a9138b9b Use CallerFInfoFunctionCall with btree_gist for varlena types
Follow up to commit 393bb504d7 which did this for numeric types.
2017-03-21 10:43:27 -04:00
Andrew Dunstan 4b1c68d63e Use CallerFInfoFunctionCall with btree_gist for numeric types
None of the existing types actually need to use this mechanism, but this
will allow support for enum types which will need it. A separate patch
will adjust the varlena types support for consistency.

Reviewed by Tom Lane and Anastasia Lubennikova

Discussion:  http://postgr.es/m/27220.1478360811@sss.pgh.pa.us
2017-03-21 10:43:27 -04:00
Peter Eisentraut fef2bcdcba pageinspect: Add page_checksum function
Author: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Reviewed-by: Ashutosh Sharma <ashu.coek88@gmail.com>
2017-03-17 10:55:17 -04:00