Commit Graph

17885 Commits

Author SHA1 Message Date
Peter Eisentraut c1869542b3 Use abstracted SSL API in server connection log messages
The existing "connection authorized" server log messages used OpenSSL
API calls directly, even though similar abstracted API calls exist.
Change to use the latter instead.

Change the function prototype for the functions that return the TLS
version and the cipher to return const char * directly instead of
copying into a buffer.  That makes them slightly easier to use.

Add bits= to the message.  psql shows that, so we might as well show the
same information on the client and server.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2018-01-26 09:50:46 -05:00
Tom Lane bb415675d8 Add missing "static" markers.
Per buildfarm.
2018-01-25 14:32:28 -05:00
Alvaro Herrera 05fb5d6619 Ignore partitioned indexes where appropriate
get_relation_info() was too optimistic about opening indexes in
partitioned tables, which would raise errors when any queries were
planned on such tables.  Fix by ignoring any indexes of the partitioned
kind.

CLUSTER (and ALTER TABLE CLUSTER ON) had a similar problem.  Fix by
disallowing these commands in partitioned tables.

Fallout from 8b08f7d482.
2018-01-25 16:12:15 -03:00
Peter Eisentraut 0b5e33f667 Remove use of byte-masking macros in record_image_cmp
These were introduced in 4cbb646334, but
after further analysis and testing, they should not be necessary and
probably weren't the part of that commit that fixed anything.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2018-01-25 09:41:19 -05:00
Robert Haas 945f71db84 Avoid referencing off the end of subplan_partition_offsets.
Report by buildfarm member skink and Tom Lane.  Analysis by me.
Patch by Amit Khandekar.

Discussion: http://postgr.es/m/CAJ3gD9fVA1iXQYhfqHP5n_TEd4U9=V8TL_cc-oKRnRmxgdvJrQ@mail.gmail.com
2018-01-24 16:34:51 -05:00
Tom Lane 434e6e1484 Improve implementation of pg_attribute_always_inline.
Avoid compiler warnings on MSVC (which doesn't want to see both
__forceinline and inline) and ancient GCC (which doesn't have
__attribute__((always_inline))).

Don't force inline-ing when building at -O0, as the programmer is probably
hoping for exact source-to-object-line correspondence in that case.
(For the moment this only works for GCC; maybe we can extend it later.)

Make pg_attribute_always_inline be syntactically a drop-in replacement
for inline, rather than an additional wart.

And improve the comments.

Thomas Munro and Michail Nikolaev, small tweaks by me

Discussion: https://postgr.es/m/32278.1514863068@sss.pgh.pa.us
Discussion: https://postgr.es/m/CANtu0oiYp74brgntKOxgg1FK5+t8uQ05guSiFU6FYz_5KUhr6Q@mail.gmail.com
2018-01-23 23:07:13 -05:00
Tom Lane bb94ce4d26 Teach reparameterize_path() to handle AppendPaths.
If we're inside a lateral subquery, there may be no unparameterized paths
for a particular child relation of an appendrel, in which case we *must*
be able to create similarly-parameterized paths for each other child
relation, else the planner will fail with "could not devise a query plan
for the given query".  This means that there are situations where we'd
better be able to reparameterize at least one path for each child.

This calls into question the assumption in reparameterize_path() that
it can just punt if it feels like it.  However, the only case that is
known broken right now is where the child is itself an appendrel so that
all its paths are AppendPaths.  (I think possibly I disregarded that in
the original coding on the theory that nested appendrels would get folded
together --- but that only happens *after* reparameterize_path(), so it's
not excused from handling a child AppendPath.)  Given that this code's been
like this since 9.3 when LATERAL was introduced, it seems likely we'd have
heard of other cases by now if there were a larger problem.

Per report from Elvis Pranskevichus.  Back-patch to 9.3.

Discussion: https://postgr.es/m/5981018.zdth1YWmNy@hammer.magicstack.net
2018-01-23 16:50:34 -05:00
Alvaro Herrera 95be5ce1bc Remove unnecessary include
autovacuum.c no longer needs dsa.h, since commit 31ae1638ce.
Author: Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoCWvYyXrvdANSHWWWEWJH5TeAWAkJ_2gqrHhukG+OBo1g@mail.gmail.com
2018-01-23 15:22:13 -03:00
Robert Haas 28e04155f1 Update obsolete sentence in README.parallel.
Since 9.6, heavyweight locking is not an abstract and unhandled
concern of the parallel machinery, but rather something to which
we have a specific approach.
2018-01-23 11:22:47 -05:00
Robert Haas 2badb5afb8 Report an ERROR if a parallel worker fails to start properly.
Commit 28724fd90d fixed things so that
if a background worker fails to start due to fork() failure or because
it is terminated before startup succeeds, BGWH_STOPPED will be
reported.  However, that only helps if the code that uses the
background worker machinery notices the change in status, and the code
in parallel.c did not.

To fix that, do two things.  First, make sure that when a worker
exits, it triggers the leader to read from error queues.  That way, if
a worker which has attached to an error queue exits uncleanly, the
leader is sure to throw some error, either the contents of the
ErrorResponse sent by the worker, or "lost connection to parallel
worker" if it exited without sending one.  To cover the case where
the worker never starts up in the first place or exits before
attaching to the error queue, the ParallelContext now keeps track
of which workers have sent at least one message via the error
queue.  A worker which sends no messages by the time the parallel
operation finishes will be checked to see whether it exited before
attaching to the error queue; if so, a new error message, "parallel
worker failed to initialize", will be reported.  If not, we'll
continue to wait until it either starts up and exits cleanly, starts
up and exits uncleanly, or fails to start, and then take the
appropriate action.

Patch by me, reviewed by Amit Kapila.

Discussion: http://postgr.es/m/CA+TgmoYnBgXgdTu6wk5YPdWhmgabYc9nY_pFLq=tB=FSLYkD8Q@mail.gmail.com
2018-01-23 11:03:03 -05:00
Peter Eisentraut 1c2183403b Extract common bits from OpenSSL implementation
Some things in be-secure-openssl.c and fe-secure-openssl.c were not
actually specific to OpenSSL but could also be used by other
implementations.  In order to avoid copy-and-pasting, move some of that
code to common files.
2018-01-23 07:11:39 -05:00
Peter Eisentraut f966101d19 Move SSL API comments to header files
Move the documentation of the SSL API calls are supposed to do into the
headers files, instead of keeping them in the files for the OpenSSL
implementation.  That way, they don't have to be duplicated or be
inconsistent when other implementations are added.
2018-01-23 07:11:39 -05:00
Peter Eisentraut 573bd08b99 Move EDH support to common files
The EDH support is not really specific to the OpenSSL implementation, so
move the support and documentation comments to common files.
2018-01-23 07:11:38 -05:00
Peter Eisentraut 7404e77cc1 Split out documentation of SSL parameters into their own section
Split the "Authentication and Security" section into two separate
sections "Authentication" and "SSL".  The latter part has gotten much
longer over time, and doesn't primarily have to do with authentication.

Also, the row_security parameter was inconsistently categorized, so
clean that up while we're here.
2018-01-23 07:11:38 -05:00
Peter Eisentraut 8561e4840c Transaction control in PL procedures
In each of the supplied procedural languages (PL/pgSQL, PL/Perl,
PL/Python, PL/Tcl), add language-specific commit and rollback
functions/commands to control transactions in procedures in that
language.  Add similar underlying functions to SPI.  Some additional
cleanup so that transaction commit or abort doesn't blow away data
structures still used by the procedure call.  Add execution context
tracking to CALL and DO statements so that transaction control commands
can only be issued in top-level procedure and block calls, not function
calls or other procedure or block calls.

- SPI

Add a new function SPI_connect_ext() that is like SPI_connect() but
allows passing option flags.  The only option flag right now is
SPI_OPT_NONATOMIC.  A nonatomic SPI connection can execute transaction
control commands, otherwise it's not allowed.  This is meant to be
passed down from CALL and DO statements which themselves know in which
context they are called.  A nonatomic SPI connection uses different
memory management.  A normal SPI connection allocates its memory in
TopTransactionContext.  For nonatomic connections we use PortalContext
instead.  As the comment in SPI_connect_ext() (previously SPI_connect())
indicates, one could potentially use PortalContext in all cases, but it
seems safest to leave the existing uses alone, because this stuff is
complicated enough already.

SPI also gets new functions SPI_start_transaction(), SPI_commit(), and
SPI_rollback(), which can be used by PLs to implement their transaction
control logic.

- portalmem.c

Some adjustments were made in the code that cleans up portals at
transaction abort.  The portal code could already handle a command
*committing* a transaction and continuing (e.g., VACUUM), but it was not
quite prepared for a command *aborting* a transaction and continuing.

In AtAbort_Portals(), remove the code that marks an active portal as
failed.  As the comment there already predicted, this doesn't work if
the running command wants to keep running after transaction abort.  And
it's actually not necessary, because pquery.c is careful to run all
portal code in a PG_TRY block and explicitly runs MarkPortalFailed() if
there is an exception.  So the code in AtAbort_Portals() is never used
anyway.

In AtAbort_Portals() and AtCleanup_Portals(), we need to be careful not
to clean up active portals too much.  This mirrors similar code in
PreCommit_Portals().

- PL/Perl

Gets new functions spi_commit() and spi_rollback()

- PL/pgSQL

Gets new commands COMMIT and ROLLBACK.

Update the PL/SQL porting example in the documentation to reflect that
transactions are now possible in procedures.

- PL/Python

Gets new functions plpy.commit and plpy.rollback.

- PL/Tcl

Gets new commands commit and rollback.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2018-01-22 08:43:06 -05:00
Magnus Hagander 1cc4f536ef Support huge pages on Windows
Add support for huge pages (called large pages on Windows) to the
Windows build.

This (probably) breaks compatibility with Windows versions prior to
Windows 2003 or Windows Vista.

Authors: Takayuki Tsunakawa and Thomas Munro
Reviewed by: Magnus Hagander, Amit Kapila
2018-01-21 15:40:46 +01:00
Tom Lane 96102a32a3 Suppress possibly-uninitialized-variable warnings.
Apparently, Peter's compiler has faith that the switch test values here
could never not be valid values of their enums.  Mine does not, and
I tend to agree with it.
2018-01-19 22:16:25 -05:00
Robert Haas 2f17844104 Allow UPDATE to move rows between partitions.
When an UPDATE causes a row to no longer match the partition
constraint, try to move it to a different partition where it does
match the partition constraint.  In essence, the UPDATE is split into
a DELETE from the old partition and an INSERT into the new one.  This
can lead to surprising behavior in concurrency scenarios because
EvalPlanQual rechecks won't work as they normally did; the known
problems are documented.  (There is a pending patch to improve the
situation further, but it needs more review.)

Amit Khandekar, reviewed and tested by Amit Langote, David Rowley,
Rajkumar Raghuwanshi, Dilip Kumar, Amul Sul, Thomas Munro, Álvaro
Herrera, Amit Kapila, and me.  A few final revisions by me.

Discussion: http://postgr.es/m/CAJ3gD9do9o2ccQ7j7+tSgiE1REY65XRiMb=yJO3u3QhyP8EEPQ@mail.gmail.com
2018-01-19 15:33:06 -05:00
Alvaro Herrera 7f17fd6fc7 Fix CompareIndexInfo's attnum comparisons
When an index column is an expression, it makes no sense to compare its
attribute numbers.

This seems to account for remaining buildfarm fallout from 8b08f7d482.
At least, it solves the issue in my local 32bit VM -- let's see what the
rest thinks.
2018-01-19 16:56:42 -03:00
Peter Eisentraut 8b9e9644dc Replace AclObjectKind with ObjectType
AclObjectKind was basically just another enumeration for object types,
and we already have a preferred one for that.  It's only used in
aclcheck_error.  By using ObjectType instead, we can also give some more
precise error messages, for example "index" instead of "relation".

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2018-01-19 14:01:15 -05:00
Peter Eisentraut 2c6f37ed62 Replace GrantObjectType with ObjectType
There used to be a lot of different *Type and *Kind symbol groups to
address objects within different commands, most of which have been
replaced by ObjectType, starting with
b256f24264.  But this conversion was never
done for the ACL commands until now.

This change ends up being just a plain replacement of the types and
symbols, without any code restructuring needed, except deleting some now
redundant code.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: Stephen Frost <sfrost@snowman.net>
2018-01-19 14:01:14 -05:00
Alvaro Herrera 8b08f7d482 Local partitioned indexes
When CREATE INDEX is run on a partitioned table, create catalog entries
for an index on the partitioned table (which is just a placeholder since
the table proper has no data of its own), and recurse to create actual
indexes on the existing partitions; create them in future partitions
also.

As a convenience gadget, if the new index definition matches some
existing index in partitions, these are picked up and used instead of
creating new ones.  Whichever way these indexes come about, they become
attached to the index on the parent table and are dropped alongside it,
and cannot be dropped on isolation unless they are detached first.

To support pg_dump'ing these indexes, add commands
    CREATE INDEX ON ONLY <table>
(which creates the index on the parent partitioned table, without
recursing) and
    ALTER INDEX ATTACH PARTITION
(which is used after the indexes have been created individually on each
partition, to attach them to the parent index).  These reconstruct prior
database state exactly.

Reviewed-by: (in alphabetical order) Peter Eisentraut, Robert Haas, Amit
	Langote, Jesper Pedersen, Simon Riggs, David Rowley
Discussion: https://postgr.es/m/20171113170646.gzweigyrgg6pwsg4@alvherre.pgsql
2018-01-19 11:49:22 -03:00
Alvaro Herrera 1ef61ddce9 Fix StoreCatalogInheritance1 to use 32bit inhseqno
For no apparent reason, this function was using a 16bit-wide inhseqno
value, rather than the correct 32 bit width which is what is stored in
the pg_inherits catalog.  This becomes evident if you try to create a
table with more than 65535 parents, because this error appears:

ERROR:  duplicate key value violates unique constraint «pg_inherits_relid_seqno_index»
DETAIL:  Key (inhrelid, inhseqno)=(329371, 0) already exists.

Needless to say, having so many parents is an uncommon situations, which
explains why this error has never been reported despite being having
been introduced with the Postgres95 1.01 sources in commit d31084e9d111:
https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/commands/creatinh.c;hb=d31084e9d111#l349

Backpatch all the way back.

David Rowley noticed this while reviewing a patch of mine.
Discussion: https://postgr.es/m/CAKJS1f8Dn7swSEhOWwzZzssW7747YB=2Hi+T7uGud40dur69-g@mail.gmail.com
2018-01-19 10:17:54 -03:00
Robert Haas 29d58fd3ad Transfer state pertaining to pending REINDEX operations to workers.
This will allow the pending patch for parallel CREATE INDEX to work
on system catalogs, and to provide the same level of protection
against use of user indexes while they are being rebuilt that we
have for non-parallel CREATE INDEX.

Patch by me, reviewed by Peter Geoghegan.

Discussion: http://postgr.es/m/CA+TgmoYN-YQU9JsGQcqFLovZ-C+Xgp1_xhJQad=cunGG-_p5gg@mail.gmail.com
Discussion: http://postgr.es/m/CAH2-Wzkv4UNkXYhqQRqk-u9rS7h5c-4cCW+EqQ8K_WSeS43aZg@mail.gmail.com
2018-01-19 07:48:54 -05:00
Simon Riggs 4e54dd2e0a Fix typo in recent commit
Typo in 9c7d06d606

Reported-by: Masahiko Sawada
2018-01-19 06:36:17 +00:00
Peter Eisentraut a228e44ce4 Update comment
The "callback" that this comment was referring to was removed by commit
c0a15e07cd, so update to match the current
code.
2018-01-18 19:36:34 -05:00
Bruce Momjian f033462d8f Reorder C includes
Reorder header files in joinrels.c and pathnode.c in alphabetical order,
removing unnecessary ones.

Author: Etsuro Fujita
2018-01-17 18:10:05 -05:00
Tom Lane dca48d145e Remove useless lookup of root partitioned rel in ExecInitModifyTable().
node->partitioned_rels is only set in UPDATE/DELETE cases, but
ExecInitModifyTable only uses its "rel" variable in INSERT cases,
so the extra logic to find the root rel is just a waste of complexity
and cycles.

Etsuro Fujita, reviewed by Amit Langote

Discussion: https://postgr.es/m/93cf9816-2f7d-0f67-8ed2-4a4e497a6ab8@lab.ntt.co.jp
2018-01-17 14:44:15 -05:00
Simon Riggs 9c7d06d606 Ability to advance replication slots
Ability to advance both physical and logical replication slots using a
new user function pg_replication_slot_advance().

For logical advance that means records are consumed as fast as possible
and changes are not given to output plugin for sending. Makes 2nd phase
(after we reached SNAPBUILD_FULL_SNAPSHOT) of replication slot creation
faster, especially when there are big transactions as the reorder buffer
does not have to deal with data changes and does not have to spill to
disk.

Author: Petr Jelinek
Reviewed-by: Simon Riggs
2018-01-17 11:38:34 +00:00
Andrew Dunstan cc4feded0a Centralize json and jsonb handling of datetime types
The creates a single function JsonEncodeDateTime which will format these
data types in an efficient and consistent manner. This will be all the
more important when we come to jsonpath so we don't have to implement yet
more code doing the same thing in two more places.

This also extends the code to handle time and timetz types which were
not previously handled specially. This requires exposing the time2tm and
timetz2tm functions.

Patch from Nikita Glukhov
2018-01-16 19:07:13 -05:00
Peter Eisentraut d91da5eced Remove useless use of bit-masking macros
In this case, the macros SET_8_BYTES(), GET_8_BYTES(), SET_4_BYTES(),
GET_4_BYTES() are no-ops, so we can just remove them.

The plan is to perhaps remove them from the source code altogether, so
we'll start here.

Discussion: https://www.postgresql.org/message-id/5d51721a-69ef-2053-9172-599b539f0628@2ndquadrant.com
2018-01-16 17:12:16 -05:00
Tom Lane 680d540502 Avoid unnecessary failure in SELECT concurrent with ALTER NO INHERIT.
If a query against an inheritance tree runs concurrently with an ALTER
TABLE that's disinheriting one of the tree members, it's possible to get
a "could not find inherited attribute" error because after obtaining lock
on the removed member, make_inh_translation_list sees that its columns
have attinhcount=0 and decides they aren't the columns it's looking for.

An ideal fix, perhaps, would avoid including such a just-removed member
table in the query at all; but there seems no way to accomplish that
without adding expensive catalog rechecks or creating a likelihood of
deadlocks.  Instead, let's just drop the check on attinhcount.  In this
way, a query that's included a just-disinherited child will still
succeed, which is not a completely unreasonable behavior.

This problem has existed for a long time, so back-patch to all supported
branches.  Also add an isolation test verifying related behaviors.

Patch by me; the new isolation test is based on Kyotaro Horiguchi's work.

Discussion: https://postgr.es/m/20170626.174612.23936762.horiguchi.kyotaro@lab.ntt.co.jp
2018-01-12 15:46:37 -05:00
Tom Lane 90947674fc Fix incorrect handling of subquery pullup in the presence of grouping sets.
If we flatten a subquery whose target list contains constants or
expressions, when those output columns are used in GROUPING SET columns,
the planner was capable of doing the wrong thing by merging a pulled-up
expression into the surrounding expression during const-simplification.
Then the late processing that attempts to match subexpressions to grouping
sets would fail to match those subexpressions to grouping sets, with the
effect that they'd not go to null when expected.

To fix, wrap such subquery outputs in PlaceHolderVars, ensuring that
they preserve their separate identity throughout the planner's expression
processing.  This is a bit of a band-aid, because the wrapper defeats
const-simplification even in places where it would be safe to allow.
But a nicer fix would likely be too invasive to back-patch, and the
consequences of the missed optimizations probably aren't large in most
cases.

Back-patch to 9.5 where grouping sets were introduced.

Heikki Linnakangas, with small mods and better test cases by me;
additional review by Andrew Gierth

Discussion: https://postgr.es/m/7dbdcf5c-b5a6-ef89-4958-da212fe10176@iki.fi
2018-01-12 12:24:50 -05:00
Alvaro Herrera 49c784ece7 Remove hard-coded schema knowledge about pg_attribute from genbki.pl
Add the ability to label a column's default value in the catalog header,
and implement this for pg_attribute.  A new function in Catalog.pm is
used to fill in a tuple with defaults.  The build process will complain
loudly if a catalog entry is incomplete,

Commit 8137f2c323 labeled variable length columns for the C preprocessor.
Expose that label to genbki.pl so we can exclude those columns from schema
macros in a general fashion. Also, format schema macro entries according
to their types.

This means slightly less code maintenance, but more importantly it's a
proving ground for mechanisms intended to be used in later commits.

While at it, I (Álvaro) couldn't resist making some changes in
genbki.pl: rename some functions to actually indicate their purpose
instead of actively misleading onlookers; and don't iterate on the whole
of pg_type to find the entry for each catalog row, using a hash instead
of an array.

Author: John Naylor, some changes by Álvaro Herrera
Discussion: https://postgr.es/m/CAJVSVGVJHwD8sfDfZW9TbCHWKf=C1YDRM-rF=2JenRU_y+VcFg@mail.gmail.com
2018-01-12 11:21:42 -03:00
Bruce Momjian bdb70c12b3 C comment: fix "the the" mentions in C comments
Reported-by: Christoph Dreis

Discussion: https://postgr.es/m/007e01d3519e$2734ca10$759e5e30$@freenet.de

Author: Christoph Dreis
2018-01-11 21:50:21 -05:00
Tom Lane 4d41b2e092 Add QueryEnvironment to ExplainOneQuery_hook's parameter list.
This should have been done in commit 18ce3a4ab, which added that parameter
to ExplainOneQuery, but it was overlooked.  This makes it impossible for
a user of the hook to pass the queryEnv down to ExplainOnePlan.

It's too late to change this API in v10, I suppose, but fortunately
passing NULL to ExplainOnePlan will work in nearly all interesting
cases in v10.  That might not be true forever, so we'd better fix it.

Tatsuro Yamada, reviewed by Thomas Munro

Discussion: https://postgr.es/m/890e8dd9-c1c7-a422-6892-874f5eaee048@lab.ntt.co.jp
2018-01-11 12:16:18 -05:00
Peter Eisentraut 9e945f8626 Fix Latin spelling
"c.f." should be "cf.".
2018-01-11 08:32:01 -05:00
Peter Eisentraut b48b2f8793 Revert "Move portal pinning from PL/pgSQL to SPI"
This reverts commit b3617cdfbb.

This broke returning unnamed cursors from PL/pgSQL functions.
Apparently, there are no test cases for this.
2018-01-10 16:01:17 -05:00
Tom Lane 3afd75eaac Remove dubious micro-optimization in ckpt_buforder_comparator().
It seems incorrect to assume that the list of CkptSortItems can never
contain duplicate page numbers: concurrent activity could result in some
page getting dropped from a low-numbered buffer and later loaded into a
high-numbered buffer while BufferSync is scanning the buffer pool.
If that happened, the comparator would give self-inconsistent results,
potentially confusing qsort().  Saving one comparison step is not worth
possibly getting the sort wrong.

So far as I can tell, nothing would actually go wrong given our current
implementation of qsort().  It might get a bit slower than expected
if there were a large number of duplicates of one value, but that's
surely a probability-epsilon case.  Still, the comment is wrong,
and if we ever switched to another sort implementation it might be
less forgiving.

In passing, avoid casting away const-ness of the argument pointers;
I've not seen any compiler complaints from that, but it seems likely
that some compilers would not like it.

Back-patch to 9.6 where this code came in, just in case I've underestimated
the possible consequences.

Discussion: https://postgr.es/m/18437.1515607610@sss.pgh.pa.us
2018-01-10 15:50:54 -05:00
Robert Haas 2fd58096f0 Add missing "return" statement to accumulate_append_subpath.
Without this, Parallel Append can end up with extra children.

Report by Rajkumar Raghuwanshi.  Fix by Amit Khandekar.  Brown
paper bag bug by me.

Discussion: http://postgr.es/m/CAKcux6mBF-NiddyEe9LwymoUC5+wh8bQJ=uk2gGkOE+L8cv=LA@mail.gmail.com
2018-01-10 11:21:20 -05:00
Peter Eisentraut b3617cdfbb Move portal pinning from PL/pgSQL to SPI
PL/pgSQL "pins" internally generated (unnamed) portals so that user code
cannot close them by guessing their names.  This logic is also useful in
other languages and really for any code.  So move that logic into SPI.
An unnamed portal obtained through SPI_cursor_open() and related
functions is now automatically pinned, and SPI_cursor_close()
automatically unpins a portal that is pinned.

In the core distribution, this affects PL/Perl and PL/Python, preventing
users from manually closing cursors created by spi_query and
plpy.cursor, respectively.  (PL/Tcl does not currently offer any cursor
functionality.)

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
2018-01-10 10:20:51 -05:00
Peter Eisentraut acc67ffd0a Give more accurate error message for dropping pinned portal
The previous code gave the same error message for attempting to drop
pinned and active portals, but those are separate states, so give
separate error messages.
2018-01-10 09:22:07 -05:00
Andres Freund 69c3936a14 Expression evaluation based aggregate transition invocation.
Previously aggregate transition and combination functions were invoked
by special case code in nodeAgg.c, evaluating input and filters
separately using the expression evaluation machinery. That turns out
to not be great for performance for several reasons:

- repeated expression evaluations have some cost
- the transition functions invocations are poorly predicted, as
  commonly there are multiple aggregates in a query, resulting in the
  same call-stack invoking different functions.
- filter and input computation had to be done separately
- the special case code made it hard to implement JITing of the whole
  transition function invocation

Address this by building one large expression that computes input,
evaluates filters, and invokes transition functions.

This leads to moderate speedups in queries bottlenecked by aggregate
computations, and enables large speedups for similar cases once JITing
is done.

There's potential for further improvement:
- It'd be nice if we could simplify the somewhat expensive
  aggstate->all_pergroups lookups.
- right now there's still an advance_transition_function invocation in
  nodeAgg.c, leading to some code duplication.

Author: Andres Freund
Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
2018-01-09 13:25:38 -08:00
Alvaro Herrera 272c2ab9fd Change some bogus PageGetLSN calls to BufferGetLSNAtomic
As src/backend/access/transam/README says, PageGetLSN may only be called
by processes holding either exclusive lock on buffer, or a shared lock
on buffer plus buffer header lock.  Therefore any place that only holds
a shared buffer lock must use BufferGetLSNAtomic instead of PageGetLSN,
which internally obtains buffer header lock prior to reading the LSN.

A few callsites failed to comply with this rule.  This was detected by
running all tests under a new (not committed) assertion that verifies
PageGetLSN locking contract.  All but one of the callsites that failed
the assertion are fixed by this patch.  Remaining callsites were
inspected manually and determined not to need any change.

The exception (unfixed callsite) is in TestForOldSnapshot, which only
has a Page argument, making it impossible to access the corresponding
Buffer from it.  Fixing that seems a much larger patch that will have to
be done separately; and that's just as well, since it was only
introduced in 9.6 and other bugs are much older.

Some of these bugs are ancient; backpatch all the way back to 9.3.

Authors: Jacob Champion, Asim Praveen, Ashwin Agrawal
Reviewed-by: Michaël Paquier
Discussion: https://postgr.es/m/CABAq_6GXgQDVu3u12mK9O5Xt5abBZWQ0V40LZCE+oUf95XyNFg@mail.gmail.com
2018-01-09 17:06:31 -03:00
Andrew Dunstan 11b623dd0a Implement TZH and TZM timestamp format patterns
These are compatible with Oracle and required for the datetime template
language for jsonpath in an upcoming patch.

Nikita Glukhov and Andrew Dunstan, reviewed by Pavel Stehule.
2018-01-09 14:25:05 -05:00
Peter Eisentraut a77dd53f30 Remove PortalGetQueryDesc()
After having gotten rid of PortalGetHeapMemory(), there seems little
reason to keep one Portal access macro around that offers no actual
abstraction and isn't consistently used anyway.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
2018-01-09 13:47:56 -05:00
Peter Eisentraut 0f7c49e855 Update portal-related memory context names and API
Rename PortalMemory to TopPortalContext, to avoid confusion with
PortalContext and align naming with similar top-level memory contexts.

Rename PortalData's "heap" field to portalContext.  The "heap" naming
seems quite antiquated and confusing.  Also get rid of the
PortalGetHeapMemory() macro and access the field directly, which we do
for other portal fields, so this abstraction doesn't buy anything.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
2018-01-09 13:47:56 -05:00
Tom Lane 3cb1b2a880 Rewrite list_qsort() to avoid trashing its input list.
The initial implementation of list_qsort(), from commit ab7271677,
re-used the ListCells of the input list while not touching the List
header.  This meant that anybody who still had a pointer to the
original header would now be in possession of a corrupted list,
a problem that seems sure to bite us eventually.

One possible solution is to re-use the original List header as well,
giving the function the semantics of update-in-place.  However, that
doesn't seem like a very good idea either given the way that the
function is used in the planner: create_path functions aren't normally
supposed to modify their input lists.  It doesn't look like there would
be a problem today, but it's not hard to foresee a time when modifying
a list of Paths in-place could have side-effects on some other append
path.

On the whole, and in view of the likelihood that this function might
be used in other contexts in the future, it seems best to get rid of
the micro-optimization of re-using the input list cells.  Just build
a new list.

Discussion: https://postgr.es/m/16912.1515449066@sss.pgh.pa.us
2018-01-09 13:25:53 -05:00
Tom Lane 624e440a47 Improve the heuristic for ordering child paths of a parallel append.
Commit ab7271677 introduced code that attempts to order the child
scans of a Parallel Append node in a way that will minimize execution
time, based on total cost and startup cost.  However, it failed to
think hard about what to do when estimated costs are exactly equal;
a case that's particularly likely to occur when comparing on startup
cost.  In such a case the ordering of the child paths would be left
to the whims of qsort, an algorithm that isn't even stable.

We can improve matters by applying the rule used elsewhere in the
planner: if total costs are equal, sort on startup cost, and
vice versa.  When both cost estimates are exactly equal, rather
than letting qsort do something unpredictable, sort based on the
child paths' relids, which should typically result in sorting in
inheritance order.  (The latter provision requires inventing a
qsort-style comparator for bitmapsets, but maybe we'll have use
for that for other reasons in future.)

This results in a few plan changes in the select_parallel test,
but those all look more reasonable than before, when the actual
underlying cost numbers are taken into account.

Discussion: https://postgr.es/m/4944.1515446989@sss.pgh.pa.us
2018-01-09 13:07:52 -05:00
Tom Lane 80259d4dbf While waiting for a condition variable, detect postmaster death.
The general assumption for postmaster child processes is that they
should just exit(1), reasonably promptly, if the postmaster disappears.
condition_variable.c neglected this consideration and could be left
waiting forever, if the counterpart process it is waiting for has
done the right thing and exited.

We had some discussion of adjusting the WaitEventSet API to make it
harder to make this type of mistake in future; but for the moment,
and for v10, let's make this narrow fix.

Discussion: https://postgr.es/m/20412.1515456143@sss.pgh.pa.us
2018-01-09 12:34:57 -05:00