When told to process all databases, clusterdb, reindexdb, and vacuumdb
would reconnect by replacing their --maintenance-db parameter with the
name of the target database. If that parameter is a connstring (which
has been allowed for a long time, though we failed to document that
before this patch), we'd lose any other options it might specify, for
example SSL or GSS parameters, possibly resulting in failure to connect.
Thus, this is the same bug as commit a45bc8a4f fixed in pg_dump and
pg_restore. We can fix it in the same way, by using libpq's rules for
handling multiple "dbname" parameters to add the target database name
separately. I chose to apply the same refactoring approach as in that
patch, with a struct to handle the command line parameters that need to
be passed through to connectDatabase. (Maybe someday we can unify the
very similar functions here and in pg_dump/pg_restore.)
Per Peter Eisentraut's comments on bug #16604. Back-patch to all
supported branches.
Discussion: https://postgr.es/m/16604-933f4b8791227b15@postgresql.org
Since commit 913bbd88d, check_sql_fn_retval() can either insert type
coercion steps in-line in the Query that produces the SQL function's
results, or generate a new top-level Query to perform the coercions,
if modifying the Query's output in-place wouldn't be safe. However,
it appears that the latter case has never actually worked, because
the code tried to inject the new Query back into the query list it was
passed ... which is not the list that will be used for later processing
when we execute the SQL function "normally" (without inlining it).
So we ended up with no coercion happening at run-time, leading to
wrong results or crashes depending on the datatypes involved.
While the regression tests look like they cover this area well enough,
through a huge bit of bad luck all the test cases that exercise the
separate-Query path were checking either inline-able cases (which
accidentally didn't have the bug) or cases that are no-ops at runtime
(e.g., varchar to text), so that the failure to perform the coercion
wasn't obvious. The fact that the cases that don't work weren't
allowed at all before v13 probably contributed to not noticing the
problem sooner, too.
To fix, get rid of the separate "flat" list of Query nodes and instead
pass the real two-level list that is going to be used later. I chose
to make the same change in check_sql_fn_statements(), although that has
no actual bug, just so that we don't need that data structure at all.
This is an API change, as evidenced by the adjustments needed to
callers outside functions.c. That's a bit scary to be doing in a
released branch, but so far as I can tell from a quick search,
there are no outside callers of these functions (and they are
sufficiently specific to our semantics for SQL-language functions that
it's not apparent why any extension would need to call them). In any
case, v13 already changed the API of check_sql_fn_retval() compared to
prior branches.
Per report from pinker. Back-patch to v13 where this code came in.
Discussion: https://postgr.es/m/1603050466566-0.post@n3.nabble.com
- Misc grammar and punctuation fixes.
- Stylistic cleanup: use spaces between function arguments and JSON fields
in examples. For example "foo(a,b)" -> "foo(a, b)". Add semicolon after
last END in a few PL/pgSQL examples that were missing them.
- Make sentence that talked about "..." and ".." operators more clear,
by avoiding to end the sentence with "..". That makes it look the same
as "..."
- Fix syntax description for HAVING: HAVING conditions cannot be repeated
Patch by Justin Pryzby, per Yaroslav Schekin's report. Backpatch to all
supported versions, to the extent that the patch applies easily.
Discussion: https://www.postgresql.org/message-id/20201005191922.GE17626%40telsasoft.com
Store the tuple conversion map to convert a tuple from a child table's
format to the root format in a new ri_ChildToRootMap field in
ResultRelInfo. It is initialized if transition tuple capture for FOR
STATEMENT triggers or INSERT tuple routing on a partitioned table is
needed. Previously, ModifyTable kept the maps in the per-subplan
ModifyTableState->mt_per_subplan_tupconv_maps array, or when tuple
routing was used, in
ResultRelInfo->ri_Partitioninfo->pi_PartitionToRootMap. The new field
replaces both of those.
Now that the child-to-root tuple conversion map is always available in
ResultRelInfo (when needed), remove the TransitionCaptureState.tcs_map
field. The callers of Exec*Trigger() functions no longer need to set or
save it, which is much less confusing and bug-prone. Also, as a future
optimization, this will allow us to delay creating the map for a given
result relation until the relation is actually processed during
execution.
Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqHtCWLdK-LO%3DNEsvOdHx%2B7yv4mE_zYK0i3BH7dXb-wxog%40mail.gmail.com
When executing DDL on a partitioned table or on a table with inheritance
children, statement-level triggers must be fired against the table given
in the original statement. The code to look that up was a bit messy and
duplicative. Commit 501ed02cf6 added a helper function,
getASTriggerResultRelInfo() (later renamed to getTargetResultRelInfo())
for it, but for some reason it was only used when firing AFTER STATEMENT
triggers and the code to fire BEFORE STATEMENT triggers duplicated the
logic.
Determine the target relation in ExecInitModifyTable(), and set it always
in ModifyTableState. Code that used to call getTargetResultRelInfo() can
now use ModifyTableState->rootResultRelInfo directly.
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqFViT47Zbr_ASBejiK7iDG8%3DQ1swQ-tjM6caRPQ67pT%3Dw%40mail.gmail.com
In shm_mq_receive(), a huge payload could trigger an unjustified
"invalid memory alloc request size" error due to the way the buffer
size is increased.
Add error checks (documenting the upper limit) and avoid the error by
limiting the allocation size to MaxAllocSize.
Author: Markus Wanner <markus.wanner@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/3bb363e7-ac04-0ac4-9fe8-db1148755bfa%402ndquadrant.com
The rules to choose the number of parallel workers to perform parallel
vacuum operation were not clearly specified.
Reported-by: Peter Eisentraut
Author: Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/36aa8aea-61b7-eb3c-263b-648e0cb117b7@2ndquadrant.com
When allocating a EVP context, it would have been possible to leak some
memory allocated directly by OpenSSL, that PostgreSQL lost track of if
the initialization of the context allocated failed. The cleanup can be
done with EVP_MD_CTX_destroy().
Note that EVP APIs exist since OpenSSL 0.9.7 and we have in the tree
equivalent implementations for older versions since ce9b75d (code
removed with 9b7cd59a as of 10~). However, in 9.5 and 9.6, the existing
code makes use of EVP_MD_CTX_destroy() and EVP_MD_CTX_create() without
an equivalent implementation when building the tree with OpenSSL 0.9.6
or older, meaning that this code is in reality broken with such versions
since it got introduced in e2838c5. As we have heard no complains about
that, it does not seem worth bothering with in 9.5 and 9.6, so I have
left that out for simplicity.
Author: Michael Paquier
Discussion: https://postgr.es/m/20201015072212.GC2305@paquier.xyz
Backpatch-through: 9.5
Given a query with enough joins, it was possible that the query planner,
after multiplying the row estimates with the join selectivity that the
estimated number of rows would exceed the limits of the double data type
and become infinite.
To give an indication on how extreme a case is required to hit this, the
particular example case reported required 379 joins to a table without any
statistics, which resulted in the 1.0/DEFAULT_NUM_DISTINCT being used for
the join selectivity. This eventually caused the row estimates to go
infinite and resulted in an assert failure in initial_cost_mergejoin()
where the infinite row estimated was multiplied by an outerstartsel of 0.0
resulting in NaN. The failing assert verified that NaN <= Inf, which is
false.
To get around this we use clamp_row_est() to cap row estimates at a
maximum of 1e100. This value is thought to be low enough that costs
derived from it would remain within the bounds of what the double type can
represent.
Aside from fixing the failing Assert, this also has the added benefit of
making it so add_path() will still receive proper numerical values as
costs which will allow it to make more sane choices when determining the
cheaper path in extreme cases such as the one described above.
Additionally, we also get rid of the isnan() checks in the join costing
functions. The actual case which originally triggered those checks to be
added in the first place never made it to the mailing lists. It seems
likely that the new code being added to clamp_row_est() will result in
those becoming checks redundant, so just remove them.
The fairly harmless assert failure problem does also exist in the
backbranches, however, a more minimalistic fix will be applied there.
Reported-by: Onder Kalaci
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/DM6PR21MB1211FF360183BCA901B27F04D80B0@DM6PR21MB1211.namprd21.prod.outlook.com
According to Microsoft's documentation, 2.2 has been the current
version since Windows 98 or so. Moreover, that's what the Postgres
backend has been requesting since 2004 (cf commit 4cdf51e64).
So there seems no reason for libpq to keep asking for 1.1.
Bring thread_test along, too, so that we're uniformly asking for 2.2
in all our WSAStartup calls.
It's not clear whether there's any point in back-patching this,
so for now I didn't.
Discussion: https://postgr.es/m/132799.1602960277@sss.pgh.pa.us
Failure to write data to a large object during restore led to an ugly
and uninformative error message. To add insult to injury, it then
fatal'd out, where other SQL-level errors usually result in pressing on.
Report the underlying error condition, rather than just giving not-very-
useful byte counts, and use warn_or_exit_horribly() so as to adhere to
pg_restore's general policy about whether to continue or not.
Also recognize that lo_write() returns int not size_t.
Per report from Justin Pryzby, though I didn't use his patch.
Given the lack of comparable complaints, I'm not sure this is
worth back-patching.
Discussion: https://postgr.es/m/20201018010232.GF9241@telsasoft.com
The Windows documentation insists that every WSAStartup call should
have a matching WSACleanup call. However, if that ever had actual
relevance, it wasn't in this century. Every remotely-modern Windows
kernel is capable of cleaning up when a process exits without doing
that, and must be so to avoid resource leaks in case of a process
crash. Moreover, Postgres backends have done WSAStartup without
WSACleanup since commit 4cdf51e64 in 2004, and we've never seen any
indication of a problem with that.
libpq's habit of doing WSAStartup during connection start and
WSACleanup during shutdown is also rather inefficient, since a
series of non-overlapping connection requests leads to repeated,
quite expensive DLL unload/reload cycles. We document a workaround
for that (having the application call WSAStartup for itself), but
that's just a kluge. It's also worth noting that it's far from
uncommon for applications to exit without doing PQfinish, and
we've not heard reports of trouble from that either.
However, the real reason for acting on this is that recent
experiments by Alexander Lakhin suggest that calling WSACleanup
during PQfinish might be triggering the symptom we occasionally see
that a process using libpq fails to emit expected stdio output.
Therefore, let's change libpq so that it calls WSAStartup only
once per process, during the first connection attempt, and never
calls WSACleanup at all.
While at it, get rid of the only other WSACleanup call in our code
tree, in pg_dump/parallel.c; that presumably is equally useless.
If this proves to suppress the fairly-common ecpg test failures
we see on Windows, I'll back-patch, but for now let's just do it
in HEAD and see what happens.
Discussion: https://postgr.es/m/ac976d8c-03df-d6b8-025c-15a2de8d9af1@postgrespro.ru
Section 8.5.1.4, which defines these literals, made only a vague
reference to the fact that they might be evaluated too soon to be
safe in non-interactive contexts. Provide a more explicit caution
against misuse. Also, generalize the wording in the related tip in
section 9.9.4: while it clearly described this problem, it implied
(or really, stated outright) that the problem only applies to table
DEFAULT clauses.
Per gripe from Tijs van Dam. Back-patch to all supported branches.
Discussion: https://postgr.es/m/c2LuRv9BiRT3bqIo5mMQiVraEXey_25B4vUn0kDqVqilwOEu_iVF1tbtvLnyQK7yDG3PFaz_GxLLPil2SDkj1MCObNRVaac-7j1dVdFERk8=@thalex.com
This changes zic's default output format from "-b fat" to "-b slim".
We were already using "slim" in v13/HEAD, so those branches drop
the explicit -b switch in the Makefiles. Instead, add an explicit
"-b fat" in v12 and before, so that we don't change the output file
format in those branches. (This is perhaps excessively conservative,
but we decided not to do so in a12079109, and I'll stick with that.)
Other non-cosmetic changes are to drop support for zic's long-obsolete
"-y" switch, and to ensure that strftime() does not change errno
unless it fails.
As usual with tzcode changes, back-patch to all supported branches.
In theory, the second px_find_digest call in px_crypt_md5 could fail
even though the first one succeeded, since resource allocation is
required. Don't skip testing for a failure. (If one did happen,
the likely result would be a crash rather than clean recovery from
an OOM failure.)
The code's been like this all along, so back-patch to all supported
branches.
Daniel Gustafsson
Discussion: https://postgr.es/m/AA8D6FE9-4AB2-41B4-98CB-AE64BA668C03@yesql.se
Commit a97e85f2b caused "exceed the available area" warnings in PDF
builds. Fine-tune colwidth values to avoid that.
Back-patch to 9.6, like the prior patch. (This is of dubious value
before v13, since we were far from free of such warnings in older
branches. But we might as well keep the SGML looking the same in all
branches.)
Per buildfarm.
Commit 32a9c0bdf introduced connection retry logic into postgres_fdw.
Previously it used goto statement for retry. This commit gets rid of that
goto from the logic to make the code simpler and easier-to-read.
When getting out of PG_CATCH() for the retry, the error state should be
cleaned up and the memory context should be reset. But commit 32a9c0bdf
forgot to do that. This commit also fixes this bug.
Previously only PQstatus()==CONNECTION_BAD was verified to detect
connection failure. But this could cause false detection in the case where
any error other than connection failure (e.g., out-of-memory) was thrown
after a broken connection was detected in libpq and CONNECTION_BAD is set.
To fix this issue, this commit changes the logic so that it also checks
the error's sqlstate is ERRCODE_CONNECTION_FAILURE.
Author: Fujii Masao
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/2943611.1602375376@sss.pgh.pa.us
Unfortunately in LLVM 3.9 LLVMGetAttributeCountAtIndex(func, index)
crashes when called with an index that has 0 attributes. Since there's
no way to work around this in the C API, add a small C++ wrapper doing
so.
The only reason this didn't fail before 72559438f9 is that there
always are function attributes...
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20201016001254.w2nfj7gd74jmb5in@alap3.anarazel.de
Backpatch: 11-, like 72559438f9
This commit required support for inline variable definition, which is
not a requirement.
RELEASE NOTE AUTHOR: the author of commit 3c0471b5fd
(pg_upgrade/tablespaces) was Justin Pryzby, not me.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/20201016001959.h24fkywfubkv2pc5@alap3.anarazel.de
Backpatch-through: 9.5
Previously, if pg_upgrade failed, and the user recreated the cluster but
did not remove the new cluster tablespace directory, a later pg_upgrade
would fail since the new tablespace directory would already exists.
This adds error reporting for this during check.
Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20200925005531.GJ23631@telsasoft.com
Backpatch-through: 9.5
Previously we only copied the function attributes. That caused problems at
least on s390x: Because we didn't copy the 'zeroext' attribute for
ExecAggTransReparent()'s *IsNull parameters, expressions invoking it didn't
ensure that the upper bytes of the registers were zeroed. In the - relatively
rare - cases where not, ExecAggTransReparent() wrongly ended up in the
newValueIsNull branch due to the register not being zero. Subsequently causing
a crash.
It's quite possible that this would cause problems on other platforms, and in
other places than just ExecAggTransReparent() on s390x.
Thanks to Christoph (and the Debian project) for providing me with access to a
s390x machine, allowing me to debug this.
Reported-By: Christoph Berg
Author: Andres Freund
Discussion: https://postgr.es/m/20201015083246.kie5726xerdt3ael@alap3.anarazel.de
Backpatch: 11-, where JIT was added
Pavan Deolasee recently noted that a few of the
HeapTupleHeaderIndicatesMovedPartitions calls added by commit
5db6df0c01 are useless, since they are done after comparing t_self
with t_ctid. But because t_self can never be set to the magical values
that indicate that the tuple moved partition, this can never succeed: if
the first test fails (so we know t_self equals t_ctid), necessarily the
second test will also fail.
So these checks can be removed and no harm is done.
Discussion: https://postgr.es/m/20200929164411.GA15497@alvherre.pgsql
We already install assorted tools for testing extensions, but these two
were missing. Having them installed, and after ISOLATION support was
added to PGXS's makefiles by d3c09b9b13, helps third-party modules
usefully include isolation tests. Compare c3a0818460.
Author: Craig Ringer <craig.ringer@enterprisedb.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAMsr+YFsCMH3B4uOPFE+2qWM6k=o=hf9LGiPNCfwqKdUPz_BsQ@mail.gmail.com
Most importantly, remove optimization in LogicalRepSyncTableStart that
skips the normal walrcv_startstreaming/endstreaming dance. The
optimization is not critically important for production uses anyway,
since it only fires in cases with no activity, and saves an
uninteresting amount of work even then. Critically, it obscures bugs by
hiding the interesting code path from test cases.
Also: in GetSubscriptionRelState, remove pointless relation open; access
pg_subscription_rel->srsubstate with GETSTRUCT as is typical rather than
SysCacheGetAttr; remove unused 'missing_ok' argument.
In wait_for_relation_state_change, use explicit catalog snapshot
invalidation rather than obscurely (and expensively) through
GetLatestSnapshot.
In various places: sprinkle comments more liberally and rewrite a number
of them. Other cosmetic code improvements.
No backpatch, since no bug is being fixed here.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Petr Jelínek <petr.jelinek@2ndquadrant.com>
Discussion: https://postgr.es/m/20201010190637.GA5774@alvherre.pgsql
The in-core equivalents can make use of built-in functions if the
compiler supports this option, making optimizations possible. 0ba99c8
replaced all existing calls in the code base at this time, but b0b39f7
(GSSAPI encryption) has forgotten to do the switch.
Discussion: https://postgr.es/m/20201014055303.GG3349@paquier.xyz
A number of places were using appendStringInfo() when they could have been
using appendStringInfoString() instead. While there's no functionality
change there, it's just more efficient to use appendStringInfoString()
when no formatting is required. Likewise for some
appendStringInfoString() calls which were just appending a single char.
We can just use appendStringInfoChar() for that.
Additionally, many places were using appendPQExpBuffer() when they could
have used appendPQExpBufferStr(). Change those too.
Patch by Zhijie Hou, but further searching by me found significantly more
places that deserved the same treatment.
Author: Zhijie Hou, David Rowley
Discussion: https://postgr.es/m/cb172cf4361e4c7ba7167429070979d4@G08CNEXMBPEKD05.g08.fujitsu.local
While registering for postmaster exit events, we have to handle a couple
of edge cases where the postmaster is already gone. Commit 815c2f09
missed one: EACCES must surely imply that PostmasterPid no longer
belongs to our postmaster process (or alternatively an unexpected
permissions model has been imposed on us). Like ESRCH, this should be
treated as a WL_POSTMASTER_DEATH event, rather than being raised with
ereport().
No known problems reported in the wild. Per code review from Tom Lane.
Back-patch to 13.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/3624029.1602701929%40sss.pgh.pa.us
during logical decoding.
Prior to commit c55040ccd0 we have no way of knowing the invalidations
before commit. So, while decoding we use to execute all the invalidations
at each command end as we had no way of knowing which invalidations
happened before that command. Due to this, transactions involving large
amounts of DDLs use to take more time and also lead to high CPU usage. But
now we know specific invalidations at each command end so we execute only
required invalidations.
It has been observed that decoding of a transaction containing truncation
of a table with 1000 partitions would be finished in 1s whereas before
this patch it used to take 4-5 minutes.
Author: Dilip Kumar
Reviewed-by: Amit Kapila and Keisuke Kuroda
Discussion: https://postgr.es/m/CANDwggKYveEtXjXjqHA6RL3AKSHMsQyfRY6bK+NqhAWJyw8psQ@mail.gmail.com
Previously it was documented that toast_tuple_target affected column
marked as only External or Extended. But this description is not correct
and toast_tuple_target affects also column marked as Main.
Back-patch to v11 where toast_tuple_target reloption was introduced.
Author: Shinya Okano
Reviewed-by: Tatsuhito Kasahara, Fujii Masao
Discussion: https://postgr.es/m/93f46e311a67422e89e770d236059817@oss.nttdata.com
I removed the duplicate command tags for START_REPLICATION inadvertently
in commit 07082b08cc, but the replication protocol requires them. The
fact that the replication protocol was broken was not noticed because
all our test cases use an optimized code path that exits early, failing
to verify that the behavior is correct for non-optimized cases. Put
them back.
Also document this protocol quirk.
Add a test case that shows the failure. It might still succeed even
without the patch when run on a fast enough server, but it suffices to
show the bug in enough cases that it would be noticed in buildfarm.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Henry Hinze <henry.hinze@gmail.com>
Reviewed-by: Petr Jelínek <petr.jelinek@2ndquadrant.com>
Discussion: https://postgr.es/m/16643-eaadeb2a1a58d28c@postgresql.org
If WaitEventSetWait() reports that the postmaster has gone away, later
calls to WaitEventSetWait() should continue to report that. Otherwise
further waits that occur in the proc_exit() path after we already
noticed the postmaster's demise could block forever.
Back-patch to 13, where the kqueue support landed.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/3624029.1602701929%40sss.pgh.pa.us
Maintaining 'es_result_relation_info' correctly at all times has become
cumbersome, especially with partitioning where each partition gets its
own result relation info. Having to set and reset it across arbitrary
operations has caused bugs in the past.
This changes all the places that used 'es_result_relation_info', to
receive the currently active ResultRelInfo via function parameters
instead.
Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
FDWs that can perform an UPDATE/DELETE remotely using the "direct modify"
set of APIs need to access the ResultRelInfo of the target table. That's
currently available in EState.es_result_relation_info, but the next
commit will remove that field.
This commit adds a new resultRelation field in ForeignScan, to store the
target relation's RT index, and the corresponding ResultRelInfo in
ForeignScanState. The FDW's PlanDirectModify callback is expected to set
'resultRelation' along with 'operation'. The core code doesn't need them
for anything, they are for the convenience of FDW's Begin- and
IterateDirectModify callbacks.
Authors: Amit Langote, Etsuro Fujita
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
Our infinite_recurse() test to verify sane stack-overrun behavior
is affected by a bug of the Linux kernel on PPC64: it will get SIGSEGV
if it receives a signal when the stack depth is (a) over 1MB and
(b) within a few kB of filling the current physical stack allocation.
See https://bugzilla.kernel.org/show_bug.cgi?id=205183.
Since this test is a bit time-consuming and we run it in parallel with
test scripts that do a lot of DDL, it can be expected to get an sinval
catchup interrupt at some point, leading to failure if the timing is
wrong. This has caused more than 100 buildfarm failures over the
past year or so.
While a fix exists for the kernel bug, it might be years before that
propagates into all production kernels, particularly in some of the
older distros we have in the buildfarm. For now, let's just back off
and not run this test on Linux PPC64; that loses nothing in test
coverage so far as our own code is concerned.
To do that, split this test into a new script infinite_recurse.sql
and skip the test when the platform name is powerpc64...-linux-gnu.
Back-patch to v12. Branches before that have not been seen to get
this failure. No doubt that's because the "errors" test was not
run in parallel with other tests before commit 798070ec0, greatly
reducing the odds of an sinval catchup being necessary.
I also back-patched 3c8553547 into v12, just so the new regression
script would look the same in all branches having it.
Discussion: https://postgr.es/m/3479046.1602607848@sss.pgh.pa.us
Discussion: https://postgr.es/m/20190723162703.GM22387%40telsasoft.com
Instead of allocating all the ResultRelInfos upfront in one big array,
allocate them in ExecInitModifyTable(). es_result_relations is now an
array of ResultRelInfo pointers, rather than an array of structs, and it
is indexed by the RT index.
This simplifies things: we get rid of the separate concept of a "result
rel index", and don't need to set it in setrefs.c anymore. This also
allows follow-up optimizations (not included in this commit yet) to skip
initializing ResultRelInfos for target relations that were not needed at
runtime, and removal of the es_result_relation_info pointer.
The EState arrays of regular result rels and root result rels are merged
into one array. Similarly, the resultRelations and rootResultRelations
lists in PlannedStmt are merged into one. It's not actually clear to me
why they were kept separate in the first place, but now that the
es_result_relations array is indexed by RT index, it certainly seems
pointless.
The PlannedStmt->resultRelations list is now only needed for
ExecRelationIsTargetRelation(). One visible effect of this change is that
ExecRelationIsTargetRelation() will now return 'true' also for the
partition root, if a partitioned table is updated. That seems like a good
thing, although the function isn't used in core code, and I don't see any
reason for an FDW to call it on a partition root.
Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
Tom Lane