Logical replication protocol uses a single byte character to identify a
message type in logical replication protocol. The code uses string
literals for the same. Use Enum so that
1. All the string literals used can be found at a single place. This
makes it easy to add more types without the risk of conflicts.
2. It's easy to locate the code handling a given message type.
3. When used with switch statements, it is easy to identify the missing
cases using -Wswitch.
Author: Ashutosh Bapat
Reviewed-by: Kyotaro Horiguchi, Andres Freund, Peter Smith and Amit Kapila
Discussion: https://postgr.es/m/CAExHW5uPzQ7L0oAd_ENyvaiYMOPgkrAoJpE+ZY5-obdcVT6NPg@mail.gmail.com
Previously we only tagged on the required information to allow the
executor to perform run-time partition pruning for Append/MergeAppend
nodes belonging to base relations. It was thought that nested
Append/MergeAppend nodes were just about always pulled up into the
top-level Append/MergeAppend and that making the run-time pruning info for
any sub Append/MergeAppend nodes was a waste of time. However, that was
likely badly thought through.
Some examples of cases we're unable to pullup nested Append/MergeAppends
are: 1) Parallel Append nodes with a mix of parallel and non-parallel
paths into a Parallel Append. 2) When planning an ordered Append scan a
sub-partition which is unordered may require a nested MergeAppend path to
ensure sub-partitions don't mix up the order of tuples being fed into the
top-level Append.
Unfortunately, it was not just as simple as removing the lines in
createplan.c which were purposefully not building the run-time pruning
info for anything but RELOPT_BASEREL relations. The code in
add_paths_to_append_rel() was far too sloppy about which partitioned_rels
it included for the Append/MergeAppend paths. The original code there
would always assume accumulate_append_subpath() would pull each sub-Append
and sub-MergeAppend path into the top-level path. While it does not
appear that there were any actual bugs caused by having the additional
partitioned table RT indexes recorded, what it did mean is that later in
planning, when we built the run-time pruning info that we wasted effort
and built PartitionedRelPruneInfos for partitioned tables that we had no
subpaths for the executor to run-time prune.
Here we tighten that up so that partitioned_rels only ever contains the RT
index for partitioned tables which actually have subpaths in the given
Append/MergeAppend. We can now Assert that every PartitionedRelPruneInfo
has a non-empty present_parts. That should allow us to catch any weird
corner cases that have been missed.
In passing, it seems there is no longer a good reason to have the
AppendPath and MergeAppendPath's partitioned_rel fields a List of IntList.
We can simply have a List of Relids instead. This is more compact in
memory and faster to add new members to. We still know which is the root
level partition as these always have a lower relid than their children.
Previously this field was used for more things, but run-time partition
pruning now remains the only user of it and it has no need for a List of
IntLists.
Here we also get rid of the RelOptInfo partitioned_child_rels field. This
is what was previously used to (sometimes incorrectly) set the
Append/MergeAppend path's partitioned_rels field. That was the only usage
of that field, so we can happily just remove it.
I also couldn't resist changing some nearby code to make use of the newly
added for_each_from macro so we can skip the first element in the list
without checking if the current item was the first one on each
iteration.
A bug report from Andreas Kretschmer prompted all this work, however,
after some consideration, I'm not personally classing this as a bug fix.
So no backpatch. In Andreas' test case, it just wasn't that clear that
there was a nested Append since the top-level Append just had a single
sub-path which was pulled up a level, per 8edd0e794.
Author: David Rowley
Reviewed-by: Amit Langote
Discussion: https://postgr.es/m/flat/CAApHDvqSchs%2BubdybcfFaSPB%2B%2BEA7kqMaoqajtP0GtZvzOOR3g%40mail.gmail.com
Statistics associated to an index got lost after running REINDEX
CONCURRENTLY, while the non-concurrent case preserves these correctly.
The concurrent and non-concurrent operations need to be consistent for
the end-user, and missing statistics would force to wait for a new
analyze to happen, which could take some time depending on the activity
of the existing autovacuum workers. This issue is fixed by copying any
existing entries in pg_statistic associated to the old index to the new
one. Note that this copy is already done with the data of the index in
the stats collector.
Reported-by: Fabrízio de Royes Mello
Author: Michael Paquier, Fabrízio de Royes Mello
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/CAFcNs+qpFPmiHd1oTXvcPdvAHicJDA9qBUSujgAhUMJyUMb+SA@mail.gmail.com
Backpatch-through: 12
Certain background workers initiate parallel queries while
debug_query_string==NULL, at which point they attempted strlen(NULL) and
died to SIGSEGV. Older debug_query_string observers allow NULL, so do
likewise in these newer ones. Back-patch to v11, where commit
7de4a1bcc5 introduced the first of these.
Discussion: https://postgr.es/m/20201014022636.GA1962668@rfd.leadboat.com
Because of this, if you tried to create an operator family with the new
sortsupport function, you got an error:
ERROR: support function number 11 is invalid for access method gist
We missed this in commit 16fa9b2b30 that added the sortsupport function,
because it only added sortsupport to a built-in operator family.
Author: Andrey Borodin
Discussion: https://www.postgresql.org/message-id/3520A18A-5C38-4697-A2E3-F3BDE3496CD5%40yandex-team.ru
On the same reasoning as in commit 36b931214, forbid using custom
oid_symbol macros in pg_type as well as pg_proc, so that we always
rely on the predictable macro names generated by genbki.pl.
We do continue to grant grandfather status to the names CASHOID and
LSNOID, although those are now considered deprecated aliases for the
preferred names MONEYOID and PG_LSNOID. This is because there's
likely to be client-side code using the old names, and this bout of
neatnik-ism doesn't quite seem worth breaking client code.
There might be a case for grandfathering EVTTRIGGEROID, too, since
externally-maintained PLs may reference that symbol. But renaming
such references to EVENT_TRIGGEROID doesn't seem like a particularly
heavy lift --- we make far more significant backend API changes in
every major release. For now I didn't add that, but we could
reconsider if there's pushback.
The other names changed here seem pretty unlikely to have any outside
uses. Again, we could add alias macros if there are complaints, but
for now I didn't.
As before, no need for a catversion bump.
John Naylor
Discussion: https://postgr.es/m/CAFBsxsHpCbjfoddNGpnnnY5pHwckWfiYkMYSF74PmP1su0+ZOw@mail.gmail.com
When ComputeXidHorizons() was called before MyDatabaseOid is set,
e.g. because a dead row in a shared relation is encountered during
InitPostgres(), the horizon for normal tables was computed too
aggressively, ignoring all backends connected to a database.
During subsequent pruning in a data table the too aggressive horizon
could end up still being used, possibly leading to still needed tuples
being removed. Not good.
This is a bug in dc7420c2c9, which the test added in 94bc27b576 made
visible, if run with force_parallel_mode set to regress. In that case
the bug is reliably triggered, because "pruning_query" is run in a
parallel worker and the start of that parallel worker is likely to
encounter a dead row in pg_database.
The fix is trivial: Compute a more pessimistic data table horizon if
MyDatabaseId is not yet known.
Author: Andres Freund
Discussion: https://postgr.es/m/20201029040030.p4osrmaywhqaesd4@alap3.anarazel.de
This adds the statistics about transactions streamed to the decoding
output plugin from ReorderBuffer. Users can query the
pg_stat_replication_slots view to check these stats and call
pg_stat_reset_replication_slot to reset the stats of a particular slot.
Users can pass NULL in pg_stat_reset_replication_slot to reset stats of
all the slots.
Commit 9868167500 has added the basic infrastructure to capture the stats
of slot and this commit extends the statistics collector to track
additional information about slots.
Bump the catversion as we have added new columns in the catalog entry.
Author: Ajin Cherian and Amit Kapila
Reviewed-by: Sawada Masahiko and Dilip Kumar
Discussion: https://postgr.es/m/CAA4eK1+chpEomLzgSoky-D31qev19AmECNiEAietPQUGEFhtVA@mail.gmail.com
This fixes a bug in the edge case where, for a temp table, heap_page_prune()
can end up with a different horizon than heap_vacuum_rel(). Which can trigger
errors like "ERROR: cannot freeze committed xmax ...".
The bug was introduced due to interaction of a7212be8b9 "Set cutoff xmin more
aggressively when vacuuming a temporary table." with dc7420c2c9 "snapshot
scalability: Don't compute global horizons while building snapshots.".
The problem is caused by lazy_scan_heap() assuming that the only reason its
HeapTupleSatisfiesVacuum() call would return HEAPTUPLE_DEAD is if the tuple is
a HOT tuple, or if the tuple's inserting transaction has aborted since the
heap_page_prune() call. But after a7212be8b9 that was also possible in other
cases for temp tables, because heap_page_prune() uses a different visibility
test after dc7420c2c9.
The fix is fairly simple: Move the special case logic for temp tables from
vacuum_set_xid_limits() to the infrastructure introduced in dc7420c2c9. That
ensures that the horizon used for pruning is at least as aggressive as the one
used by lazy_scan_heap(). The concrete horizon used for temp tables is
slightly different than the logic in dc7420c2c9, but should always be as
aggressive as before (see comments).
A significant benefit to centralizing the logic procarray.c is that now the
more aggressive horizons for temp tables does not just apply to VACUUM but
also to e.g. HOT pruning and the nbtree killtuples logic.
Because isTopLevel is not needed by vacuum_set_xid_limits() anymore, I
undid the the related changes from a7212be8b9.
This commit also adds an isolation test ensuring that the more aggressive
vacuuming and pruning of temp tables keeps working.
Debugged-By: Amit Kapila <amit.kapila16@gmail.com>
Debugged-By: Tom Lane <tgl@sss.pgh.pa.us>
Debugged-By: Ashutosh Sharma <ashu.coek88@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20201014203103.72oke6hqywcyhx7s@alap3.anarazel.de
Discussion: https://postgr.es/m/20201015083735.derdzysdtqdvxshp@alap3.anarazel.de
It's unsafe to do this at parse time because addition of generated
columns to a table would not invalidate stored rules containing
UPDATEs on the table ... but there might now be dependent generated
columns that were not there when the rule was made. This also fixes
an oversight that rewriteTargetView failed to update extraUpdatedCols
when transforming an UPDATE on an updatable view. (Since the new
calculation is downstream of that, rewriteTargetView doesn't actually
need to do anything; but before, there was a demonstrable bug there.)
In v13 and HEAD, this leads to easily-visible bugs because (since
commit c6679e4fc) we won't recalculate generated columns that aren't
listed in extraUpdatedCols. In v12 this bitmap is mostly just used
for trigger-firing decisions, so you'd only notice a problem if a
trigger cared whether a generated column had been updated.
I'd complained about this back in May, but then forgot about it
until bug #16671 from Michael Paul Killian revived the issue.
Back-patch to v12 where this field was introduced. If existing
stored rules contain any extraUpdatedCols values, they'll be
ignored because the rewriter will overwrite them, so the bug will
be fixed even for existing rules. (But note that if someone were
to update to 13.1 or 12.5, store some rules with UPDATEs on tables
having generated columns, and then downgrade to a prior minor version,
they might observe issues similar to what this patch fixes. That
seems unlikely enough to not be worth going to a lot of effort to fix.)
Discussion: https://postgr.es/m/10206.1588964727@sss.pgh.pa.us
Discussion: https://postgr.es/m/16671-2fa55851859fb166@postgresql.org
We have a perfectly good convention for OID macros for built-in functions
already, so making custom symbols is just introducing unnecessary
deviation from the convention. Remove the one case that had snuck in,
and add an error check in genbki.pl to discourage future instances.
Although this touches pg_proc.dat, there's no need for a catversion
bump since the actual catalog data isn't changed.
John Naylor
Discussion: https://postgr.es/m/CAFBsxsHpCbjfoddNGpnnnY5pHwckWfiYkMYSF74PmP1su0+ZOw@mail.gmail.com
get_foreign_key_join_selectivity() looks for join clauses that equate
the two sides of the FK constraint. However, if we have a query like
"WHERE fktab.a = pktab.a and fktab.a = 1", it won't find any such join
clause, because equivclass.c replaces the given clauses with "fktab.a
= 1 and pktab.a = 1", which can be enforced at the scan level, leaving
nothing to be done for column "a" at the join level.
We can fix that expectation without much trouble, but then a new problem
arises: applying the foreign-key-based selectivity rule produces a
rowcount underestimate, because we're effectively double-counting the
selectivity of the "fktab.a = 1" clause. So we have to cancel that
selectivity out of the estimate.
To fix, refactor process_implied_equality() so that it can pass back the
new RestrictInfo to its callers in equivclass.c, allowing the generated
"fktab.a = 1" clause to be saved in the EquivalenceClass's ec_derives
list. Then it's not much trouble to dig out the relevant RestrictInfo
when we need to adjust an FK selectivity estimate. (While at it, we
can also remove the expensive use of initialize_mergeclause_eclasses()
to set up the new RestrictInfo's left_ec and right_ec pointers.
The equivclass.c code can set those basically for free.)
This seems like clearly a bug fix, but I'm hesitant to back-patch it,
first because there's some API/ABI risk for extensions and second because
we're usually loath to destabilize plan choices in stable branches.
Per report from Sigrid Ehrenreich.
Discussion: https://postgr.es/m/1019549.1603770457@sss.pgh.pa.us
Discussion: https://postgr.es/m/AM6PR02MB5287A0ADD936C1FA80973E72AB190@AM6PR02MB5287.eurprd02.prod.outlook.com
This makes use of CheckBuffer() introduced in c780a7a, adding a SQL
wrapper able to do checks for all the pages of a relation. By default,
all the fork types of a relation are checked, and it is possible to
check only a given relation fork. Note that if the relation given in
input has no physical storage or is temporary, then no errors are
generated, allowing full-database checks when coupled with a simple scan
of pg_class for example. This is not limited to clusters with data
checksums enabled, as clusters without data checksums can still apply
checks on pages using the page headers or for the case of a page full of
zeros.
This function returns a set of tuples consisting of:
- The physical file where a broken page has been detected (without the
segment number as that can be AM-dependent, which can be guessed from
the block number for heap). A relative path from PGPATH is used.
- The block number of the broken page.
By default, only superusers have an access to this function but
execution rights can be granted to other users.
The feature introduced here is still minimal, and more improvements
could be done, like:
- Addition of a start and end block number to run checks on a range
of blocks, which would apply only if one fork type is checked.
- Addition of some progress reporting.
- Throttling, with configuration parameters in function input or
potentially some cost-based GUCs.
Regression tests are added for positive cases in the main regression
test suite, and TAP tests are added for cases involving the emulation of
page corruptions.
Bump catalog version.
Author: Julien Rouhaud, Michael Paquier
Reviewed-by: Masahiko Sawada, Justin Pryzby
Discussion: https://postgr.es/m/CAOBaU_aVvMjQn=ge5qPiJOPMmOj5=ii3st5Q0Y+WuLML5sR17w@mail.gmail.com
CheckBuffer() is designed to be a concurrent-safe function able to run
sanity checks on a relation page without loading it into the shared
buffers. The operation is done using a lock on the partition involved
in the shared buffer mapping hashtable and an I/O lock for the buffer
itself, preventing the risk of false positives due to any concurrent
activity.
The primary use of this function is the detection of on-disk corruptions
for relation pages. If a page is found in shared buffers, the on-disk
page is checked if not dirty (a follow-up checkpoint would flush a valid
version of the page if dirty anyway), as it could be possible that a
page was present for a long time in shared buffers with its on-disk
version corrupted. Such a scenario could lead to a corrupted cluster if
a host is plugged off for example. If the page is not found in shared
buffers, its on-disk state is checked. PageIsVerifiedExtended() is used
to apply the same sanity checks as when a page gets loaded into shared
buffers.
This function will be used by an upcoming patch able to check the state
of on-disk relation pages using a SQL function.
Author: Julien Rouhaud, Michael Paquier
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/CAOBaU_aVvMjQn=ge5qPiJOPMmOj5=ii3st5Q0Y+WuLML5sR17w@mail.gmail.com
This accompanies select_common_type() and select_common_collation().
Typmods were previously combined using hand-coded logic in several
places. The logic in select_common_typmod() isn't very exciting, but
it makes the code more compact and readable in a few locations, and in
the future we can perhaps do more complicated things if desired.
As a small enhancement, the type unification of the direct and
aggregate arguments of hypothetical-set aggregates now unifies the
typmod as well using this new function, instead of just dropping it.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://www.postgresql.org/message-id/flat/97df3af9-8b5e-fb7f-a029-3eb7e80d7af9@2ndquadrant.com
The restriction that only tables and views can be locked by LOCK TABLE
is quite arbitrary, since the underlying mechanism can lock any relation
type. Drop the restriction so that programs such as pg_dump can lock
all relations they're interested in, preventing schema changes that
could cause a dump to fail after expending much effort.
Backpatch to 9.5.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Wells Oliver <wells.oliver@gmail.com>
Discussion: https://postgr.es/m/20201021200659.GA32358@alvherre.pgsql
Previously, ExecInitModifyTable relied on ExecInitJunkFilter,
and thence ExecCleanTypeFromTL, to build the target descriptor from
the query tlist. While we just checked (in ExecCheckPlanOutput)
that the tlist produces compatible output, this is not a great
substitute for the relation's actual tuple descriptor that's
available from the relcache. For one thing, dropped columns will
not be correctly marked attisdropped; it's a bit surprising that
we've gotten away with that this long. But the real reason for
being concerned with this is that using the table's descriptor means
that the slot will have correct attrmissing data, allowing us to
revert the klugy fix of commit ba9f18abd. (This commit undoes
that one's changes in trigger.c, but keeps the new test case.)
Thus we can solve the bogus-trigger-tuple problem with fewer cycles
rather than more.
No back-patch, since this doesn't fix any additional bug, and it
seems somewhat more likely to have unforeseen side effects than
ba9f18abd's narrow fix.
Discussion: https://postgr.es/m/16644-5da7ef98a7ac4545@postgresql.org
This is useful for checks of relation pages without having to load the
pages into the shared buffers, and two cases can make use of that: page
verification in base backups and the online, lock-safe, flavor.
Compatibility is kept with past versions using a macro that calls the
new extended routine with the set of options compatible with the
original version.
Extracted from a larger patch by the same author.
Author: Anastasia Lubennikova
Reviewed-by: Michael Paquier, Julien Rouhaud
Discussion: https://postgr.es/m/608f3476-0598-2514-2c03-e05c7d2b0cbd@postgrespro.ru
If the old row has any "missing" attributes that are supposed to
be retrieved from an associated tuple descriptor, the wrong things
happened because the trigger result is shoved directly into an
executor slot that lacks the missing-attribute data. Notably,
CHECK-constraint verification would incorrectly see those columns
as NULL, and so would RETURNING-list evaluation.
Band-aid around this by forcibly expanding the tuple before passing
it to the trigger function. (IMO it was a fundamental misdesign to
put the missing-attribute data into tuple constraints, which so
much of the system considers to be optional. But we're probably
stuck with that now, and will have to continue to apply band-aids
as we find other places with similar issues.)
Back-patch to v12. v11 would also have the issue, except that
commit 920311ab1 already applied a similar band-aid. That forced
expansion in more cases than seem really necessary, though, so
this isn't a directly equivalent fix.
Amit Langote, with some cosmetic changes by me
Discussion: https://postgr.es/m/16644-5da7ef98a7ac4545@postgresql.org
The ExplainCloseGroup arguments for incremental sort usage data
didn't match the corresponding ExplainOpenGroup. This only matters
for XML-format output, which is probably why we'd not noticed.
Daniel Gustafsson, per bug #16683 from Frits Jalvingh
Discussion: https://postgr.es/m/16683-8005033324ad34e9@postgresql.org
There is a handful of places where we called list_delete_ptr() to remove
some element from a List. In many of these places we know, or with very
little additional effort know the index of the ListCell that we need to
remove.
Here we change all of those places to instead either use one of;
list_delete_nth_cell(), foreach_delete_current() or list_delete_last().
Each of these saves from having to iterate over the list to search for the
element to remove by its pointer value.
There are some small performance gains to be had by doing this, but in the
general case, none of these lists are likely to be very large, so the
lookup was probably never that expensive anyway. However, some of the
calls are in fairly hot code paths, e.g process_equivalence(). So any
small gains there are useful.
Author: Zhijie Hou and David Rowley
Discussion: https://postgr.es/m/b3517353ec7c4f87aa560678fbb1034b@G08CNEXMBPEKD05.g08.fujitsu.local
After de8feb1f3a, some warnings remained
that were only visible when using GCC on Windows. Fix those as well.
Note that the ecpg test source files don't use the full pg_config.h,
so we can't use pg_funcptr_t there but have to do it the long way.
More precisely, correctly handle the ONLY flag indicating not to
recurse. This was implemented in 86f575948c by recursing in
trigger.c, but that's the wrong place; use ATSimpleRecursion instead,
which behaves properly. However, because legacy inheritance has never
recursed in that situation, make sure to do that only for new-style
partitioning.
I noticed this problem while testing a fix for another bug in the
vicinity.
This has been wrong all along, so backpatch to 11.
Discussion: https://postgr.es/m/20201016235925.GA29829@alvherre.pgsql
Change the attribute 'name' to 'slot_name' in pg_stat_replication_slots
view to make it clear and that way we will be consistent with the other
places like pg_stat_wal_receiver view where we display the same attribute.
In the passing, fix the typo in one of the macros in the related code.
Bump the catversion as we have modified the name in the catalog as well.
Reported-by: Noriyoshi Shinoda
Author: Noriyoshi Shinoda
Reviewed-by: Sawada Masahiko and Amit Kapila
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
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
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
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
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
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
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
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