Commit Graph

9583 Commits

Author SHA1 Message Date
913bbd88dc Improve the handling of result type coercions in SQL functions.
Use the parser's standard type coercion machinery to convert the
output column(s) of a SQL function's final SELECT or RETURNING
to the type(s) they should have according to the function's declared
result type.  We'll allow any case where an assignment-level
coercion is available.  Previously, we failed unless the required
coercion was a binary-compatible one (and the documentation ignored
this, falsely claiming that the types must match exactly).

Notably, the coercion now accounts for typmods, so that cases where
a SQL function is declared to return a composite type whose columns
are typmod-constrained now behave as one would expect.  Arguably
this aspect is a bug fix, but the overall behavioral change here
seems too large to consider back-patching.

A nice side-effect is that functions can now be inlined in a
few cases where we previously failed to do so because of type
mismatches.

Discussion: https://postgr.es/m/18929.1574895430@sss.pgh.pa.us
2020-01-08 11:07:59 -05:00
ce242ae154 tableam: New callback relation_fetch_toast_slice.
Instead of always calling heap_fetch_toast_slice during detoasting,
invoke a table AM callback which, when the toast table is a heap
table, will be heap_fetch_toast_slice.

This makes it possible for a table AM other than heap to be used
as a TOAST table. It also completes the series of commits intended
to improve the interaction of tableam with TOAST that began with
commit 8b94dab06617ef80a0901ab103ebd8754427ef5a; detoast.c is
now, hopefully, fully AM-independent.

Patch by me, reviewed by Andres Freund and Peter Eisentraut.

Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
2020-01-07 14:36:38 -05:00
83322e38da tableam: Allow choice of toast AM.
Previously, the toast table had to be implemented by the same AM that
was used for the main table, which was bad, because the detoasting
code won't work with anything but heap. This commit doesn't fix the
latter problem, although there's another patch coming which does,
but it does let you pick something that works (i.e. heap, right now).

Patch by me, reviewed by Andres Freund.

Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
2020-01-07 14:23:25 -05:00
20d6225d16 Add functions min_scale(numeric) and trim_scale(numeric).
These allow better control of trailing zeroes in numeric values.

Pavel Stehule, based on an old proposal of Marko Tiikkaja's;
review by Karl Pinc

Discussion: https://postgr.es/m/CAFj8pRDjs-navGASeF0Wk74N36YGFJ+v=Ok9_knRa7vDc-qugg@mail.gmail.com
2020-01-06 12:13:53 -05:00
5b630501e9 Skip memcpy(x, x) in qunique().
It has undefined behavior.  Follow the precedent of commit
9a9473f3cce1a21c25d6cc7569710e832d2b180b.  No back-patch, since the
master branch alone has this function.

Discussion: https://postgr.es/m/20191229070221.GA13873@gust.leadboat.com
2020-01-04 11:31:42 -08:00
3fd40b628c Make better use of ParseState in ProcessUtility
Pass ParseState into the functions called from
standard_ProcessUtility() instead passing the query string and query
environment separately.  No functionality change, but it makes the
notation consistent.  We had already started moving things into
that direction piece by piece, and this completes it.

Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/6e7aa4a1-be6a-1a75-b1f9-83a678e5184a@2ndquadrant.com
2020-01-04 13:12:41 +01:00
d2e5e20e57 Add xl_btree_delete optimization.
Commit 558a9165e08 taught _bt_delitems_delete() to produce its own XID
horizon on the primary.  Standbys no longer needed to generate their own
latestRemovedXid, since they could just use the explicitly logged value
from the primary instead.  The deleted offset numbers array from the
xl_btree_delete WAL record was no longer used by the REDO routine for
anything other than deleting the items.

This enables a minor optimization:  We now treat the array as buffer
state, not generic WAL data, following _bt_delitems_vacuum()'s example.
This should be a minor win, since it allows us to avoid including the
deleted items array in cases where XLogInsert() stores the whole buffer
anyway.  The primary goal here is to make the code more maintainable,
though.  Removing inessential differences between the two functions
highlights the fundamental differences that remain.

Also change xl_btree_delete to use uint32 for the size of the array of
item offsets being deleted.  This brings xl_btree_delete closer to
xl_btree_vacuum.  Furthermore, it seems like a good idea to use an
explicit-width integer type (the field was previously an "int").

Bump XLOG_PAGE_MAGIC because xl_btree_delete changed.

Discussion: https://postgr.es/m/CAH2-Wzkz4TjmezzfAbaV1zYrh=fr0bCpzuJTvBe5iUQ3aUPsCQ@mail.gmail.com
2020-01-03 12:18:13 -08:00
a412f46988 Reorder two nbtree.h function prototypes.
Make the function prototype order consistent with the definition order
in nbtpage.c.
2020-01-02 10:57:15 -08:00
5815696bc6 Make parser rely more heavily on the ParseNamespaceItem data structure.
When I added the ParseNamespaceItem data structure (in commit 5ebaaa494),
it wasn't very tightly integrated into the parser's APIs.  In the wake of
adding p_rtindex to that struct (commit b541e9acc), there is a good reason
to make more use of it: by passing around ParseNamespaceItem pointers
instead of bare RTE pointers, we can get rid of various messy methods for
passing back or deducing the rangetable index of an RTE during parsing.
Hence, refactor the addRangeTableEntryXXX functions to build and return
a ParseNamespaceItem struct, not just the RTE proper; and replace
addRTEtoQuery with addNSItemToQuery, which is passed a ParseNamespaceItem
rather than building one internally.

Also, add per-column data (a ParseNamespaceColumn array) to each
ParseNamespaceItem.  These arrays are built during addRangeTableEntryXXX,
where we have column type data at hand so that it's nearly free to fill
the data structure.  Later, when we need to build Vars referencing RTEs,
we can use the ParseNamespaceColumn info to avoid the rather expensive
operations done in get_rte_attribute_type() or expandRTE().
get_rte_attribute_type() is indeed dead code now, so I've removed it.
This makes for a useful improvement in parse analysis speed, around 20%
in one moderately-complex test query.

The ParseNamespaceColumn structs also include Var identity information
(varno/varattno).  That info isn't actually being used in this patch,
except that p_varno == 0 is a handy test for a dropped column.
A follow-on patch will make more use of it.

Discussion: https://postgr.es/m/2461.1577764221@sss.pgh.pa.us
2020-01-02 11:29:01 -05:00
7559d8ebfa Update copyrights for 2020
Backpatch-through: update all files in master, backpatch legal files through 9.4
2020-01-01 12:21:45 -05:00
7854e07f25 Revert "Rename files and headers related to index AM"
This follows multiple complains from Peter Geoghegan, Andres Freund and
Alvaro Herrera that this issue ought to be dug more before actually
happening, if it happens.

Discussion: https://postgr.es/m/20191226144606.GA5659@alvherre.pgsql
2019-12-27 08:09:00 +09:00
fbe0232358 Improve comments in utils/rel.h.
Mark the fields that should be accessed via partitioning-related
functions, as we already did for some other fields.

Amit Langote

Discussion: https://postgr.es/m/CA+HiwqFnK6LbVMACMCaqwWrvoSFTecZzufKRahg2qGvLPYMX=g@mail.gmail.com
2019-12-26 11:20:05 -05:00
b541e9accb Refactor parser's generation of Var nodes.
Instead of passing around a pointer to the RangeTblEntry that
provides the desired column, pass a pointer to the associated
ParseNamespaceItem.  The RTE is trivially reachable from the nsitem,
and having the ParseNamespaceItem allows access to additional
information.  As proof of concept for that, add the rangetable index
to ParseNamespaceItem, and use that to get rid of RTERangeTablePosn
searches.

(I have in mind to teach the parser to generate some different
representation for Vars that are nullable by outer joins, and
keeping the necessary information in ParseNamespaceItems seems
like a reasonable approach to that.  But whether that ever
happens or not, this seems like good cleanup.)

Also refactor the code around scanRTEForColumn so that the
"fuzzy match" stuff does not leak out of parse_relation.c.

Discussion: https://postgr.es/m/26144.1576858373@sss.pgh.pa.us
2019-12-26 11:16:42 -05:00
bb4114a4e2 Allow whole-row Vars to be used in partitioning expressions.
In the wake of commit 5b9312378, there's no particular reason
for this restriction (previously, it was problematic because of
the implied rowtype reference).  A simple constraint on a whole-row
Var probably isn't that useful, but conceivably somebody would want
to pass one to a function that extracts a partitioning key.  Besides
which, we're expending much more code to enforce the restriction than
we save by having it, since the latter quantity is now zero.
So drop the restriction.

Amit Langote

Discussion: https://postgr.es/m/CA+HiwqFUzjfj9HEsJtYWcr1SgQ_=iCAvQ=O2Sx6aQxoDu4OiHw@mail.gmail.com
2019-12-25 15:44:15 -05:00
42f74f4936 Remove equalPartitionDescs().
This is dead code in the wake of the previous commit.
We can always add it back if we need it again someday.

Discussion: https://postgr.es/m/CA+HiwqFUzjfj9HEsJtYWcr1SgQ_=iCAvQ=O2Sx6aQxoDu4OiHw@mail.gmail.com
2019-12-25 14:45:57 -05:00
5b9312378e Load relcache entries' partitioning data on-demand, not immediately.
Formerly the rd_partkey and rd_partdesc data structures were always
populated immediately when a relcache entry was built or rebuilt.
This patch changes things so that they are populated only when they
are first requested.  (Hence, callers *must* now always use
RelationGetPartitionKey or RelationGetPartitionDesc; just fetching
the pointer directly is no longer acceptable.)

This seems to have some performance benefits, but the main reason to do
it is that it eliminates a recursive-reload failure that occurs if the
partkey or partdesc expressions contain any references to the relation's
rowtype (as discovered by Amit Langote).  In retrospect, since loading
these data structures might result in execution of nearly-arbitrary code
via eval_const_expressions, it was a dumb idea to require that to happen
during relcache entry rebuild.

Also, fix things so that old copies of a relcache partition descriptor
will be dropped when the cache entry's refcount goes to zero.  In the
previous coding it was possible for such copies to survive for the
lifetime of the session, as I'd complained of in a previous discussion.
(This management technique still isn't perfect, but it's better than
before.)  Improve the commentary explaining how that works and why
it's safe to hand out direct pointers to these relcache substructures.

In passing, improve RelationBuildPartitionDesc by using the same
memory-context-parent-swap approach used by RelationBuildPartitionKey,
thereby making it less dependent on strong assumptions about what
partition_bounds_copy does.  Avoid doing get_rel_relkind in the
critical section, too.

Patch by Amit Langote and Tom Lane; Robert Haas deserves some credit
for prior work in the area, too.  Although this is a pre-existing
problem, no back-patch: the patch seems too invasive to be safe to
back-patch, and the bug it fixes is a corner case that seems
relatively unlikely to cause problems in the field.

Discussion: https://postgr.es/m/CA+HiwqFUzjfj9HEsJtYWcr1SgQ_=iCAvQ=O2Sx6aQxoDu4OiHw@mail.gmail.com
Discussion: https://postgr.es/m/CA+TgmoY3bRmGB6-DUnoVy5fJoreiBJ43rwMrQRCdPXuKt4Ykaw@mail.gmail.com
2019-12-25 14:43:13 -05:00
8ce3aa9b59 Rename files and headers related to index AM
The following renaming is done so as source files related to index
access methods are more consistent with table access methods (the
original names used for index AMs ware too generic, and could be
confused as including features related to table AMs):
- amapi.h -> indexam.h.
- amapi.c -> indexamapi.c.  Here we have an equivalent with
backend/access/table/tableamapi.c.
- amvalidate.c -> indexamvalidate.c.
- amvalidate.h -> indexamvalidate.h.
- genam.c -> indexgenam.c.
- genam.h -> indexgenam.h.

This has been discussed during the development of v12 when table AM was
worked on, but the renaming never happened.

Author: Michael Paquier
Reviewed-by: Fabien Coelho, Julien Rouhaud
Discussion: https://postgr.es/m/20191223053434.GF34339@paquier.xyz
2019-12-25 10:23:39 +09:00
e69d644547 Rotate instead of shifting hash join batch number.
Our algorithm for choosing batch numbers turned out not to work
effectively for multi-billion key inner relations.  We would use
more hash bits than we have, and effectively concentrate all tuples
into a smaller number of batches than we intended.  While ideally
we should switch to wider hashes, for now, change the algorithm to
one that effectively gives up bits from the bucket number when we
don't have enough bits.  That means we'll finish up with longer
bucket chains than would be ideal, but that's better than having
batches that don't fit in work_mem and can't be divided.

Batch-patch to all supported releases.

Author: Thomas Munro
Reviewed-by: Tom Lane, thanks also to Tomas Vondra, Alvaro Herrera, Andres Freund for testing and discussion
Reported-by: James Coleman
Discussion: https://postgr.es/m/16104-dc11ed911f1ab9df%40postgresql.org
2019-12-24 13:05:43 +13:00
39ebb943de Disallow partition key expressions that return pseudo-types.
This wasn't checked originally, but it should have been, because
in general pseudo-types can't be stored to and retrieved from disk.
Notably, partition bound values of type "record" would not be
interpretable by another session.

In v12 and HEAD, add another flag to CheckAttributeType's repertoire
so that it can produce a specific error message for this case.  That's
infeasible in older branches without an ABI break, so fall back to
a slightly-less-nicely-worded error message in v10 and v11.

Problem noted by Amit Langote, though this patch is not his initial
solution.  Back-patch to v10 where partitioning was introduced.

Discussion: https://postgr.es/m/CA+HiwqFUzjfj9HEsJtYWcr1SgQ_=iCAvQ=O2Sx6aQxoDu4OiHw@mail.gmail.com
2019-12-23 12:53:12 -05:00
696cc3a0ca Normalize _bt_finish_split() argument names.
Make a function prototype argument's name match the function
definition's argument name.
2019-12-22 20:07:45 -08:00
8f4fb4c648 Generate pg_config.h from pg_config.h.in on Windows
Previously, the Windows MSVC build generated pg_config.h from a
hard-coded pg_config.h.win32 with some ad hoc postprocessing.  The
pg_config.h.win32 file required manual maintenance and was as a result
frequently out of date.

Instead, have the MSVC build scripts emulate what configure and
config.status do: collect a list of defines and then create
pg_config.h from pg_config.h.in by changing the appropriate lines.

The previous setup was made to support old Windows build systems that
didn't have any text processing capabilities, but the current system
has Perl, so it's not a problem.  pg_config.h.win32 is removed.

In order to try to keep the Windows side of things more up to date in
the future, we now also require that all symbols found in
pg_config.h.in are defined in the MSVC build system.  So if there is a
change in configure that results in a new symbol, an update in
Solution.pm will be required.

The other headers managed by AC_CONFIG_HEADERS in configure, namely
src/include/pg_config_ext.h and
src/interfaces/ecpg/include/ecpg_config.h, get the same treatment, so
this removes even more ad hoc code in the MSVC build scripts.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/1441b834-f434-e0bf-46ed-9c4d5c29c2d4%402ndquadrant.com
2019-12-20 09:15:08 +01:00
16a4e4aecd Extend the ProcSignal mechanism to support barriers.
A new function EmitProcSignalBarrier() can be used to emit a global
barrier which all backends that participate in the ProcSignal
mechanism must absorb, and a new function WaitForProcSignalBarrier()
can be used to wait until all relevant backends have in fact
absorbed the barrier.

This can be used to coordinate global state changes, such as turning
checksums on while the system is running.

There's no real client of this mechanism yet, although two are
proposed, but an enum has to have at least one element, so this
includes a placeholder type (PROCSIGNAL_BARRIER_PLACEHOLDER) which
should be replaced by the first real client of this mechanism to
get committed.

Andres Freund and Robert Haas, reviewed by Daniel Gustafsson and,
in earlier versions, by Magnus Hagander.

Discussion: http://postgr.es/m/CA+TgmoZwDk=BguVDVa+qdA6SBKef=PKbaKDQALTC_9qoz1mJqg@mail.gmail.com
2019-12-19 14:56:20 -05:00
9f83468b35 Remove unneeded "pin scan" nbtree VACUUM code.
The REDO routine for nbtree's xl_btree_vacuum record type hasn't
performed a "pin scan" since commit 3e4b7d87 went in, so clearly there
isn't any point in VACUUM WAL-logging information that won't actually be
used.  Finish off the work of commit 3e4b7d87 (and the closely related
preceding commit 687f2cd7) by removing the code that generates this
unused information.  Also remove the REDO routine code disabled by
commit 3e4b7d87.

Replace the unneeded lastBlockVacuumed field in xl_btree_vacuum with a
new "ndeleted" field.  The new field isn't actually needed right now,
since we could continue to infer the array length from the overall
record length.  However, an upcoming patch to add deduplication to
nbtree needs to add an "items updated" field to xl_btree_vacuum, so we
might as well start being explicit about the number of items now.
(Besides, it doesn't seem like a good idea to leave the xl_btree_vacuum
struct without any fields; the C standard says that that's undefined.)

nbtree VACUUM no longer forces writing a WAL record for the last block
in the index.  Writing out a WAL record with no items for the final
block was supposed to force processing of a lastBlockVacuumed field by a
pin scan.

Bump XLOG_PAGE_MAGIC because xl_btree_vacuum changed.

Discussion: https://postgr.es/m/CAH2-WzmY_mT7UnTzFB5LBQDBkKpdV5UxP3B5bLb7uP%3D%3D6UQJRQ%40mail.gmail.com
2019-12-19 11:35:55 -08:00
303640199d Fix minor problems with non-exclusive backup cleanup.
The previous coding imagined that it could call before_shmem_exit()
when a non-exclusive backup began and then remove the previously-added
handler by calling cancel_before_shmem_exit() when that backup
ended. However, this only works provided that nothing else in the
system has registered a before_shmem_exit() hook in the interim,
because cancel_before_shmem_exit() is documented to remove a callback
only if it is the latest callback registered. It also only works
if nothing can ERROR out between the time that sessionBackupState
is reset and the time that cancel_before_shmem_exit(), which doesn't
seem to be strictly true.

To fix, leave the handler installed for the lifetime of the session,
arrange to install it just once, and teach it to quietly do nothing if
there isn't a non-exclusive backup in process.

This is a bug, but for now I'm not going to back-patch, because the
consequences are minor. It's possible to cause a spurious warning
to be generated, but that doesn't really matter. It's also possible
to trigger an assertion failure, but production builds shouldn't
have assertions enabled.

Patch by me, reviewed by Kyotaro Horiguchi, Michael Paquier (who
preferred a different approach, but got outvoted), Fujii Masao,
and Tom Lane, and with comments by various others.

Discussion: http://postgr.es/m/CA+TgmobMjnyBfNhGTKQEDbqXYE3_rXWpc4CM63fhyerNCes3mA@mail.gmail.com
2019-12-19 09:06:54 -05:00
bf7427bdd3 Minimal portability fix for commit e1551f96e.
Older gcc versions are not happy with having multiple declarations
for the same typedef name (not struct name).  I'm a bit dubious
as to how well-thought-out that patch was at all, but for the moment
just fix it enough so I can get some work done today.

Discussion: https://postgr.es/m/20191218101338.GB325369@paquier.xyz
2019-12-18 10:22:50 -05:00
e1551f96e6 Refactor attribute mappings used in logical tuple conversion
Tuple conversion support in tupconvert.c is able to convert rowtypes
between two relations, inner and outer, which are logically equivalent
but have a different ordering or even dropped columns (used mainly for
inheritance tree and partitions).  This makes use of attribute mappings,
which are simple arrays made of AttrNumber elements with a length
matching the number of attributes of the outer relation.  The length of
the attribute mapping has been treated as completely independent of the
mapping itself until now, making it easy to pass down an incorrect
mapping length.

This commit refactors the code related to attribute mappings and moves
it into an independent facility called attmap.c, extracted from
tupconvert.c.  This merges the attribute mapping with its length,
avoiding to try to guess what is the length of a mapping to use as this
is computed once, when the map is built.

This will avoid mistakes like what has been fixed in dc816e58, which has
used an incorrect mapping length by matching it with the number of
attributes of an inner relation (a child partition) instead of an outer
relation (a partitioned table).

Author: Michael Paquier
Reviewed-by: Amit Langote
Discussion: https://postgr.es/m/20191121042556.GD153437@paquier.xyz
2019-12-18 16:23:02 +09:00
da41d71070 simplehash: Allow for use in frontend code.
Commit 48995040d5e7b1e9bac35d72aff326cae002219d removed the largest
barrier to use of simplehash in frontend code, but there's one more
problem: it uses elog(ERROR, ...) or elog(LOG, ...) in a couple of
places. Work around that by changing those to pg_log_error() and
pg_log_info() when FRONTEND is defined.

Patch by me, reviewed by Andres Freund.

Discussion: http://postgr.es/m/CA+Tgmob8oyh02NrZW=xCScB+5GyJ-jVowE3+TWTUmPF=FsGWTA@mail.gmail.com
2019-12-17 14:14:32 -05:00
48995040d5 simplehash: Allow use of simplehash without MemoryContext.
If the SH_RAW_ALLOCATOR is defined, it will be used to allocate bytes
for the hash table, and no dependencies on MemoryContext will exist.
This means, in particular, that the SH_CREATE function will not take
a MemoryContext argument.

Patch by me, reviewed by Andres Freund.

Discussion: http://postgr.es/m/CA+Tgmob8oyh02NrZW=xCScB+5GyJ-jVowE3+TWTUmPF=FsGWTA@mail.gmail.com
2019-12-17 14:06:25 -05:00
7dbfea3c45 Partially deduplicate interrupt handling for background processes.
Where possible, share signal handler code and main loop interrupt
checking. This saves quite a bit of code and should simplify
maintenance, too.

This commit intends not to change the way anything works, even
though that might allow more code to be unified. It does unify
a bunch of individual variables into a ShutdownRequestPending
flag that has is now used by a bunch of different process types,
though.

Patch by me, reviewed by Andres Freund and Daniel Gustafsson.

Discussion: http://postgr.es/m/CA+TgmoZwDk=BguVDVa+qdA6SBKef=PKbaKDQALTC_9qoz1mJqg@mail.gmail.com
2019-12-17 13:14:28 -05:00
fcf3b6917b Rename nbtree tuple macros.
Rename two function-style macros, removing the word "inner".  This makes
things more consistent.
2019-12-16 17:49:45 -08:00
5d43c3c54d Fix query cancellation handling in psql
The refactoring done in a4fd3aa for query cancellation has messed up
with the logic in psql by mixing CancelRequested and cancel_pressed,
breaking for example \watch.  The former would be switched to true if a
cancellation request has been attempted and that it actually succeeded,
and the latter tracks if a cancellation attempt has been done.

This commit brings back the code of psql to a state consistent to what
it was before a4fd3aa, without giving up on the refactoring pieces
introduced.  It should be actually possible to merge more both flags as
their concepts are close enough, however note that psql's --single-step
mode relies on cancel_pressed to be always set, so this requires more
careful analysis left for later.

While on it, fix the declarations of CancelRequested (in cancel.c) and
cancel_pressed (in psql) to be volatile sig_atomic_t.  Previously,
both were declared as booleans, which should be fine on modern
platforms, but the C standard recommends the use of sig_atomic_t for
variables used in signal handlers.  Note that since its introduction in
a1792320, CancelRequested declaration was not volatile.

Reported-by: Jeff Janes
Author: Michael Paquier
Discussion: https://postgr.es/m/CAMkU=1zpoUDGKqWKuMWkj7t-bOCaJDx0r=5te_-d0B2HVLABXg@mail.gmail.com
2019-12-17 10:44:25 +09:00
b925a00f4e Fix "force_parallel_mode = regress" to work with ANALYZE + VERBOSE.
force_parallel_mode = regress is supposed to force use of a Gather
node without having any impact on EXPLAIN output.  But it failed to
accomplish that if both ANALYZE and VERBOSE are given, because that
enables per-worker output data that you wouldn't see if the Gather
hadn't been inserted.  Improve the logic so that we suppress the
per-worker data too.

This allows putting the new test case added by commit 5935917ce
back into the originally intended form (cf. 776a2c887, 22864f6e0).
We can also get rid of a kluge in subselect.sql, which previously
had to clean up after force_parallel_mode's failure to do what it
said on the tin.

Discussion: https://postgr.es/m/18445.1576177309@sss.pgh.pa.us
2019-12-16 20:14:35 -05:00
502423180a Fix build of Perl-using modules of Windows
Commit f14413b684d57211068ee56ee04695efcc87a23a broke the build of
Perl-using modules on Windows.

Perl might have its own definitions of uid_t and gid_t, so we hide
ours, but then we can't use ours in our header files such as port.h
which don't see the Perl definition.

Hide our definition of getpeereid() on Windows in Perl-using modules,
using PLPERL_HAVE_UID_GID define.  That means we can't portably use
getpeeruid() is such modules right now, but there is no need anyway.
2019-12-16 11:48:01 +01:00
f14413b684 Sort out getpeereid() and peer auth handling on Windows
The getpeereid() uses have so far been protected by HAVE_UNIX_SOCKETS,
so they didn't ever care about Windows support.  But in anticipation
of Unix-domain socket support on Windows, that needs to be handled
differently.

Windows doesn't support getpeereid() at this time, so we use the
existing not-supported code path.  We let configure do its usual thing
of picking up the replacement from libpgport, instead of the custom
overrides that it was doing before.

But then Windows doesn't have struct passwd, so this patch sprinkles
some additional #ifdef WIN32 around to make it work.  This is similar
to existing code that deals with this issue.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/5974caea-1267-7708-40f2-6009a9d653b0@2ndquadrant.com
2019-12-16 09:36:08 +01:00
6ea364e7e7 Prevent overly-aggressive collapsing of joins to RTE_RESULT relations.
The RTE_RESULT simplification logic added by commit 4be058fe9 had a
flaw: it would collapse out a RTE_RESULT that is due to compute a
PlaceHolderVar, and reassign the PHV to the parent join level, even if
another input relation of the join contained a lateral reference to
the PHV.  That can't work because the PHV would be computed too late.
In practice it led to failures of internal sanity checks later in
planning (either assertion failures or errors such as "failed to
construct the join relation").

To fix, add code to check for the presence of such PHVs in relevant
portions of the query tree.  Notably, this required refactoring
range_table_walker so that a caller could ask to walk individual RTEs
not the whole list.  (It might be a good idea to refactor
range_table_mutator in the same way, if only to keep those functions
looking similar; but I didn't do so here as it wasn't necessary for
the bug fix.)

This exercise also taught me that find_dependent_phvs(), as it stood,
could only safely be used on the entire Query, not on subtrees.
Adjust its API to reflect that; which in passing allows it to have
a fast path for the common case of no PHVs anywhere.

Per report from Will Leinweber.  Back-patch to v12 where the bug
was introduced.

Discussion: https://postgr.es/m/CALLb-4xJMd4GZt2YCecMC95H-PafuWNKcmps4HLRx2NHNBfB4g@mail.gmail.com
2019-12-14 13:49:15 -05:00
5935917ce5 Allow executor startup pruning to prune all child nodes.
Previously, if the startup pruning logic proved that all child nodes
of an Append or MergeAppend could be pruned, we still kept one, just
to keep EXPLAIN from failing.  The previous commit removed the
ruleutils.c limitation that required this kluge, so drop it.  That
results in less-confusing EXPLAIN output, as per a complaint from
Yuzuko Hosoya.

David Rowley

Discussion: https://postgr.es/m/001001d4f44b$2a2cca50$7e865ef0$@lab.ntt.co.jp
2019-12-11 17:05:30 -05:00
6ef77cf46e Further adjust EXPLAIN's choices of table alias names.
This patch causes EXPLAIN to always assign a separate table alias to the
parent RTE of an append relation (inheritance set); before, such RTEs
were ignored if not actually scanned by the plan.  Since the child RTEs
now always have that same alias to start with (cf. commit 55a1954da),
the net effect is that the parent RTE usually gets the alias used or
implied by the query text, and the children all get that alias with "_N"
appended.  (The exception to "usually" is if there are duplicate aliases
in different subtrees of the original query; then some of those original
RTEs will also have "_N" appended.)

This results in more uniform output for partitioned-table plans than
we had before: the partitioned table itself gets the original alias,
and all child tables have aliases with "_N", rather than the previous
behavior where one of the children would get an alias without "_N".

The reason for giving the parent RTE an alias, even if it isn't scanned
by the plan, is that we now use the parent's alias to qualify Vars that
refer to an appendrel output column and appear above the Append or
MergeAppend that computes the appendrel.  But below the append, Vars
refer to some one of the child relations, and are displayed that way.
This seems clearer than the old behavior where a Var that could carry
values from any child relation was displayed as if it referred to only
one of them.

While at it, change ruleutils.c so that the code paths used by EXPLAIN
deal in Plan trees not PlanState trees.  This effectively reverts a
decision made in commit 1cc29fe7c, which seemed like a good idea at
the time to make ruleutils.c consistent with explain.c.  However,
it's problematic because we'd really like to allow executor startup
pruning to remove all the children of an append node when possible,
leaving no child PlanState to resolve Vars against.  (That's not done
here, but will be in the next patch.)  This requires different handling
of subplans and initplans than before, but is otherwise a pretty
straightforward change.

Discussion: https://postgr.es/m/001001d4f44b$2a2cca50$7e865ef0$@lab.ntt.co.jp
2019-12-11 17:05:18 -05:00
ba79cb5dc8 Emit parameter values during query bind/execute errors
This makes such log entries more useful, since the cause of the error
can be dependent on the parameter values.

Author: Alexey Bashtanov, Álvaro Herrera
Discussion: https://postgr.es/m/0146a67b-a22a-0519-9082-bc29756b93a2@imap.cc
Reviewed-by: Peter Eisentraut, Andres Freund, Tom Lane
2019-12-11 18:03:35 -03:00
877b61e9ce Cosmetic cleaning of pg_config.h.win32
Clean up some comments (some generated by old versions of autoconf)
and some random ordering differences, so it's easier to diff this
against the default pg_config.h or pg_config.h.in.  Remove LOCALEDIR
handling from pg_config.h.win32 altogether because it's already in
pg_config_paths.h.
2019-12-10 21:24:25 +01:00
6cafde1bd4 Add backend-only appendStringInfoStringQuoted
This provides a mechanism to emit literal values in informative
messages, such as query parameters.  The new code is more complex than
what it replaces, primarily because it wants to be more efficient.
It also has the (currently unused) additional optional capability of
specifying a maximum size to print.

The new function lives out of common/stringinfo.c so that frontend users
of that file need not pull in unnecessary multibyte-encoding support
code.

Author: Álvaro Herrera and Alexey Bashtanov, after a suggestion from Andres Freund
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20190920203905.xkv5udsd5dxfs6tr@alap3.anarazel.de
2019-12-10 17:12:56 -03:00
30d47723fd Fix comments in execGrouping.c
Commit 5dfc1981 missed updating some comments.

Also, fix a comment typo found in passing.

Author: Jeff Davis
Discussion: https://postgr.es/m/9723131d247b919f94699152647fa87ee0bc02c2.camel%40j-davis.com
2019-12-06 11:49:59 -08:00
7d0bcb0477 Fix handling of OpenSSL's SSL_clear_options
This function is supported down to OpenSSL 0.9.8, which is the oldest
version supported since 593d4e4 (from Postgres 10 onwards), and is used
since e3bdb2d (from 11 onwards).  It is defined as a macro from OpenSSL
0.9.8 to 1.0.2, and as a function in 1.1.0 and newer versions.  However,
the configure check present is only adapted for functions.  So, even if
the code would be able to compile, configure fails to detect the macro,
causing it to be ignored when compiling the code with OpenSSL from 0.9.8
to 1.0.2.

The code needs a configure check as per a364dfa, which has fixed a
compilation issue with a past version of LibreSSL in NetBSD 5.1.  On
HEAD, just remove the configure check as the last release of NetBSD 5 is
from 2014 (and we have no more buildfarm members for it).  In 11 and 12,
improve the configure logic so as both macros and functions are
correctly detected.  This makes NetBSD 5 still work on already-released
branches, but not for 13 onwards.

The patch for HEAD is from me, and Daniel has written the version to use
for the back-branches.

Author: Michael Paquier, Daniel Gustaffson
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20191205083252.GE5064@paquier.xyz
Discussion: https://postgr.es/m/98F7F99E-1129-41D8-B86B-FE3B1E286881@yesql.se
Backpatch-through: 11
2019-12-06 15:13:55 +09:00
28f4bba66b Remove configure check for OpenSSL's SSL_get_current_compression()
This function has been added in OpenSSL 0.9.8, which is the oldest
version supported on HEAD, so checking for it at configure time is
useless.  Both the frontend and backend code did not even bother to use
it.

Reported-by: Daniel Gustafsson
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion: https://postgr.es/m/20191205083252.GE5064@paquier.xyz
Discussion: https://postgr.es/m/98F7F99E-1129-41D8-B86B-FE3B1E286881@yesql.se
2019-12-06 09:41:32 +09:00
42f362967d Minor comment improvements for instrumentation.h
Remove a duplicated word. Add "of" or "# of" in a couple places
for clarity and consistency. Start comments with a lower case
letter as we do elsewhere in this file.

Rafia Sabih
2019-12-05 07:56:29 -05:00
0b9466fce2 Offer pnstrdup to frontend code
We already had it on the backend.  Frontend can also use it now.

Discussion: https://postgr.es/m/20191204144021.GA17976@alvherre.pgsql
2019-12-04 19:36:06 -03:00
9989d37d1c Remove XLogFileNameP() from the tree
XLogFileNameP() is a wrapper routine able to build a palloc'd string for
a WAL segment name, which is used for error string generation.  There
were several code paths where it gets called in a critical section,
where memory allocation is not allowed.  This results in triggering
an assertion failure instead of generating the wanted error message.

Another, more annoying, problem is that if the allocation to generate
the WAL segment name fails on OOM, then the failure would be escalated
to a PANIC.

This removes the routine and all its callers are replaced with a logic
using a fixed-size buffer.  This way, all the existing mistakes are
fixed and future ones are prevented.

Author: Masahiko Sawada
Reviewed-by: Michael Paquier, Álvaro Herrera
Discussion: https://postgr.es/m/CA+fd4k5gC9H4uoWMLg9K_QfNrnkkdEw+-AFveob9YX7z8JnKTA@mail.gmail.com
2019-12-03 15:06:04 +09:00
ce76c0ba53 Add a reverse-translation column number array to struct AppendRelInfo.
This provides for cheaper mapping of child columns back to parent
columns.  The one existing use-case in examine_simple_variable()
would hardly justify this by itself; but an upcoming bug fix will
make use of this array in a mainstream code path, and it seems
likely that we'll find other uses for it as we continue to build
out the partitioning infrastructure.

Discussion: https://postgr.es/m/12424.1575168015@sss.pgh.pa.us
2019-12-02 18:05:29 -05:00
a4fd3aa719 Refactor query cancellation code into src/fe_utils/
Originally, this code was duplicated in src/bin/psql/ and
src/bin/scripts/, but it can be useful for other frontend applications,
like pgbench.  This refactoring offers the possibility to setup a custom
callback which would get called in the signal handler for SIGINT or when
the interruption console events happen on Windows.

Author: Fabien Coelho, with contributions from Michael Paquier
Reviewed-by: Álvaro Herrera, Ibrar Ahmed
Discussion: https://postgr.es/m/alpine.DEB.2.21.1910311939430.27369@lancre
2019-12-02 11:18:56 +09:00
c35b714caf Fix misbehavior with expression indexes on ON COMMIT DELETE ROWS tables.
We implement ON COMMIT DELETE ROWS by truncating tables marked that
way, which requires also truncating/rebuilding their indexes.  But
RelationTruncateIndexes asks the relcache for up-to-date copies of any
index expressions, which may cause execution of eval_const_expressions
on them, which can result in actual execution of subexpressions.
This is a bad thing to have happening during ON COMMIT.  Manuel Rigger
reported that use of a SQL function resulted in crashes due to
expectations that ActiveSnapshot would be set, which it isn't.
The most obvious fix perhaps would be to push a snapshot during
PreCommit_on_commit_actions, but I think that would just open the door
to more problems: CommitTransaction explicitly expects that no
user-defined code can be running at this point.

Fortunately, since we know that no tuples exist to be indexed, there
seems no need to use the real index expressions or predicates during
RelationTruncateIndexes.  We can set up dummy index expressions
instead (we do need something that will expose the right data type,
as there are places that build index tupdescs based on this), and
just ignore predicates and exclusion constraints.

In a green field it'd likely be better to reimplement ON COMMIT DELETE
ROWS using the same "init fork" infrastructure used for unlogged
relations.  That seems impractical without catalog changes though,
and even without that it'd be too big a change to back-patch.
So for now do it like this.

Per private report from Manuel Rigger.  This has been broken forever,
so back-patch to all supported branches.
2019-12-01 13:09:26 -05:00
c676e659b2 Fix choose_best_statistics to check clauses individually
When picking the best extended statistics object for a list of clauses,
it's not enough to look at attnums extracted from the clause list as a
whole. Consider for example this query with OR clauses:

   SELECT * FROM t WHERE (t.a = 1) OR (t.b = 1) OR (t.c = 1)

with a statistics defined on columns (a,b). Relying on attnums extracted
from the whole OR clause, we'd consider the statistics usable. That does
not work, as we see the conditions as a single OR-clause, referencing an
attribute not covered by the statistic, leading to empty list of clauses
to be estimated using the statistics and an assert failure.

This changes choose_best_statistics to check which clauses are actually
covered, and only using attributes from the fully covered ones. For the
previous example this means the statistics object will not be considered
as compatible with the OR-clause.

Backpatch to 12, where MCVs were introduced. The issue does not affect
older versions because functional dependencies don't handle OR clauses.

Author: Tomas Vondra
Reviewed-by: Dean Rasheed
Reported-By: Manuel Rigger
Discussion: https://postgr.es/m/CA+u7OA7H5rcE2=8f263w4NZD6ipO_XOrYB816nuLXbmSTH9pQQ@mail.gmail.com
Backpatch-through: 12
2019-11-28 22:20:45 +01:00