16.4のリリース後(pg164tail)のdoc_ja_16の更新をdoc_ja_17にマージしました #3090
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This is confusing, as it exports twice the same variable. Oversight in 6782709 that has spread in more places afterwards. Reported-by: Alvaro Herrera, Tom Lane Discussion: https://postgr.es/m/[email protected] Backpatch-through: 17
These tests depend on the test module injection_points to be installed, but it may not be available as the contents of src/test/modules/ are not installed by default. This commit adds a workaround based on a scan of pg_available_extensions to check if the extension is available, skipping the test if it is not. This allows installcheck to work transparently. There are more tests impacted by this problem on HEAD, but for now this addresses only the tests that exist on HEAD and v17 as the release is close by. Reported-by: Maxim Orlov Discussion: https://postgr.es/m/CACG=ezZkoT-pFz6a9XnyToiuR-Wg8fGELqHLoyBodr+2h-77qA@mail.gmail.com Backpatch-through: 17
This term was using an inconsistent casing between the code and the documentation, using "CommitTsSLRU" in wait_event_names.txt and "CommitTSSLRU" in the code. Let's update the term in the code to reflect what's in the documentation, "CommitTs" being more commonly used, so as pg_stat_activity shows the same term as the documentation. Oversight in 53c2a97. Author: Alexander Lakhin Discussion: https://postgr.es/m/[email protected] Backpatch-through: 17
Since commit 2549f06, we reject an identifier immediately following a numeric literal (without separating whitespace), because that risks ambiguity with hex/octal/binary integers. However, that patch used token patterns like "{integer}{ident_start}", which is problematic because {ident_start} matches only a single byte. If the first character after the integer is a multibyte character, this ends up with flex reporting an error message that includes a partial multibyte character. That can cause assorted bad-encoding problems downstream, both in the report to the client and in the postmaster log file. To fix, use {identifier} not {ident_start} in the "junk" token patterns, so that they will match complete multibyte characters. This seems generally better user experience quite aside from the encoding problem: for "123abc" the error message will now say that the error appeared at or near "123abc" instead of "123a". While at it, add some commentary about why these patterns exist and how they work. Report and patch by Karina Litskevich; review by Pavel Borisov. Back-patch to v15 where the problem came in. Discussion: https://postgr.es/m/CACiT8iZ_diop=0zJ7zuY3BXegJpkKK1Av-PU7xh0EDYHsa5+=g@mail.gmail.com
commit 60ae37a Backpatch-through: 17 only
The updated comment provides more helpful guidance by mentioning that escontext should be set when soft error handling is needed. Reported-by: Jian He <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
The deparsing code in get_json_expr_options() unnecessarily emitted the default column-specific ON ERROR / EMPTY behavior when the top-level ON ERROR behavior in JSON_TABLE was set to ERROR. Fix that by not overriding the column-specific default, determined based on the column's JsonExprOp in get_json_table_columns(), with JSON_BEHAVIOR_ERROR when that is the top-level ON ERROR behavior. Note that this only removes redundancy; the current deparsing output is not incorrect, just redundant. Reviewed-by: Jian He <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
Use EMPTY ARRAY instead of EMPTY. This change does not affect the runtime behavior of JSON_TABLE(), which continues to return an empty relation ON ERROR. It only alters whether the default ON ERROR behavior is shown in the deparsed output. Reported-by: Jian He <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
When the ON ERROR / ON EMPTY behavior is to return NULL, returning NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's no need to create separate steps to check the error/empty flag or those to evaluate the the constant NULL expression. This speeds up common cases because the default ON ERROR / ON EMPTY behavior for JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps are necessary if the RETURNING type is a domain, as constraints on the domain may need to be checked. Reported-by: Jian He <[email protected]> Author: Jian He <[email protected]> Author: Amit Langote <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
The deparsing code in get_json_expr_options() unnecessarily emitted the default column-specific ON ERROR / EMPTY behavior when the top-level ON ERROR behavior in JSON_TABLE was set to ERROR. Fix that by not overriding the column-specific default, determined based on the column's JsonExprOp in get_json_table_columns(), with JSON_BEHAVIOR_ERROR when that is the top-level ON ERROR behavior. Note that this only removes redundancy; the current deparsing output is not incorrect, just redundant. Reviewed-by: Jian He <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
Use EMPTY ARRAY instead of EMPTY. This change does not affect the runtime behavior of JSON_TABLE(), which continues to return an empty relation ON ERROR. It only alters whether the default ON ERROR behavior is shown in the deparsed output. Reported-by: Jian He <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
pg_stat_get_io() applied TimestampTzGetDatum twice to the stat_reset_timestamp value. On 64-bit builds that's harmless because TimestampTzGetDatum is a no-op, but on 32-bit builds it results in displaying garbage in the stats_reset column of the pg_stat_io view. Bug dates to commit a9c70b4 which introduced pg_stat_io, so back-patch to v16 where that came in. Bertrand Drouvot Discussion: https://postgr.es/m/[email protected]
…essions As introduced by f9900df, a REINDEX CONCURRENTLY job done for an index with predicates or expressions would set PROC_IN_SAFE_IC in its MyProc->statusFlags, causing it to be ignored by other concurrent operations. Such concurrent index rebuilds should never be ignored, as a predicate or an expression could call a user-defined function that accesses a different table than the table where the index is rebuilt. A test that uses injection points is added, backpatched down to 17. Michail has proposed a different test, but I have added something simpler with more coverage. Oversight in f9900df. Author: Michail Nikolaev Discussion: https://postgr.es/m/CANtu0oj9A3kZVduFTG0vrmGnKB+DCHgEpzOp0qAyOgmks84j0w@mail.gmail.com Backpatch-through: 14
When the ON ERROR / ON EMPTY behavior is to return NULL, returning NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's no need to create separate steps to check the error/empty flag or those to evaluate the the constant NULL expression. This speeds up common cases because the default ON ERROR / ON EMPTY behavior for JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps are necessary if the RETURNING type is a domain, as constraints on the domain may need to be checked. Reported-by: Jian He <[email protected]> Author: Jian He <[email protected]> Author: Amit Langote <[email protected]> Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com Backpatch-through: 17
We must drop whitespace while parsing the input, else libxml2 will include "blank" nodes that interfere with the desired indentation behavior. The end result is that we didn't indent nodes separated by whitespace. Also, it seems that libxml2 may add a trailing newline when working in DOCUMENT mode. This is semantically insignificant, so strip it. This is in the gray area between being a bug fix and a definition change. However, the INDENT option is still pretty new (since v16), so I think we can get away with changing this in stable branches. Hence, back-patch to v16. Jim Jones Discussion: https://postgr.es/m/[email protected]
When building a JSON object, the code builds a hash table of keys, to allow checking if the keys are unique. The uniqueness check and adding the new key happens in json_unique_check_key(), but this assumes the pointer to the key remains valid. Unfortunately, two places passed pointers to keys in a buffer, while also appending more data (additional key/value pairs) to the buffer. With enough data the buffer is resized by enlargeStringInfo(), which calls repalloc(), invalidating the earlier key pointers. Due to this the uniqueness check may fail with both false negatives and false positives, producing JSON objects with duplicate keys or failing to produce a perfectly valid JSON object. This affects multiple functions that enforce uniqueness of keys, all introduced in PG16 with the new SQL/JSON: - json_object_agg_unique / jsonb_object_agg_unique - json_object / jsonb_objectagg Existing regression tests did not detect the issue, simply because the initial buffer size is 1024 and the objects were small enough not to require the repalloc. With a sufficiently large object, AddressSanitizer reported the access to invalid memory immediately. So would valgrind, of course. Fixed by copying the key into the hash table memory context, and adding regression tests with enough data to repalloc the buffer. Backpatch to 16, where the functions were introduced. Reported by Alexander Lakhin. Investigation and initial fix by Junwang Zhao, with various improvements and tests by me. Reported-by: Alexander Lakhin Author: Junwang Zhao, Tomas Vondra Backpatch-through: 16 Discussion: https://postgr.es/m/[email protected] Discussion: https://postgr.es/m/CAEG8a3JjH0ReJF2_O7-8LuEbO69BxPhYeXs95_x7+H9AMWF1gw@mail.gmail.com
check_agglevels_and_constraints() asserted that if we find an aggregate function in an EXPR_KIND_FROM_SUBSELECT expression, the expression must be in a LATERAL subquery. Alexander Lakhin found a case where that's not so: because of the odd scoping rules for NEW/OLD within a rule, a reference to NEW/OLD could cause an aggregate to be considered top-level even though it's in an unmarked sub-select. The error message that would be thrown seems sufficiently on-point, so just remove the Assert. (Hence, this is not a bug for production builds.) This Assert was added by me in commit eaccfde (9.3 era). It looks like I put it in to cross-check that the new logic for detecting misplaced aggregates (using agglevelsup) caught the same cases that a previous check on p_lateral_active did. So there might have been some related misbehavior before eaccfde ... but that's very ancient history by now, so I didn't dig any deeper. Per bug #18608 from Alexander Lakhin. Back-patch to all supported branches. Discussion: https://postgr.es/m/[email protected]
Currently, when WITH CONDITIONAL WRAPPER is specified, array wrappers are applied even to a single SQL/JSON item if it is a scalar JSON value, but this behavior does not comply with the standard. To fix, apply wrappers only when there are multiple SQL/JSON items in the result. Reported-by: Peter Eisentraut <[email protected]> Author: Peter Eisentraut <[email protected]> Author: Amit Langote <[email protected]> Reviewed-by: Andrew Dunstan <[email protected]> Discussion: https://postgr.es/m/8022e067-818b-45d3-8fab-6e0d94d03626%40eisentraut.org Backpatch-through: 17
A few recent JSON aggregates have been added without much consideration to the existing order. Put these back in alphabetical order (with the exception of the JSONB variant of each JSON aggregate). Author: Wolfgang Walther <[email protected]> Reviewed-by: Marlene Reiterer <[email protected]> Discussion: https://postgr.es/m/6a7b910c-3feb-4006-b817-9b4759cb6bb6%40technowledgy.de Backpatch-through: 16, where these aggregates were added
Discussion of commit ed055d2 revealed that we don't actually want jsonpath's .string() method to depend on DateStyle, nor TimeZone either, because the non-"_tz" jsonpath functions are supposed to be immutable. Potentially we could allow a TimeZone dependency in the "_tz" variants, but it seems better to just uniformly define this method as returning the same string that jsonb text output would do. That's easier to implement too, saving a couple dozen lines. Patch by me, per complaint from Peter Eisentraut. Back-patch to v17 where this feature came in (in 66ea94e). Also back-patch ed055d2 to provide test cases. Discussion: https://postgr.es/m/[email protected]
Commit 4b82664 restricted a number of functions provided by contrib modules to only relations that use the "heap" table access method. Sequences always use this table access method, but they do not advertise as such in the pg_class system catalog, so the aforementioned commit also (presumably unintentionally) removed support for sequences from some of these functions. This commit reintroduces said support for sequences to these functions and adds a couple of relevant tests. Co-authored-by: Ayush Vatsa Reviewed-by: Robert Haas, Michael Paquier, Matthias van de Meent Discussion: https://postgr.es/m/CACX%2BKaP3i%2Bi9tdPLjF5JCHVv93xobEdcd_eB%2B638VDvZ3i%3DcQA%40mail.gmail.com Backpatch-through: 12
Commit 2c27346 fixed the behavior of JSON_QUERY() when WITH CONDITIONAL WRAPPER is used, but the documentation example wasn't updated to reflect this change. This commit updates the example to show the correct result. Per off-list report from Andreas Ulbrich. Backpatch-through: 17
Copied from SGML comments. Discussion: https://postgr.es/m/CACJufxF+9YCDce5vzmZY6ZCEeTJsYFG-kPohT9UjKikJX30mGw@mail.gmail.com Author: jian he Backpatch-through: 17 only
I managed to break this test in two different ways in commit 05036a3. First, the output of the new call to tuple_data_split() on the test sequence is dependent on endianness. This is fixed by setting a special start value for the test sequence that produces the same output regardless of the endianness of the machine. Second, on versions older than v15, the new test case fails under "force_parallel_mode = regress" with the following error: ERROR: cannot access temporary tables during a parallel operation This is because pageinspect's disk-accessing functions are incorrectly marked PARALLEL SAFE on versions older than v15 (see commit aeaaf52 for details). This one is fixed by changing the test sequence to be permanent. The only reason it was previously marked temporary was to avoid needing a DROP SEQUENCE command at the end of the test. Unlike some other tests in this file, the use of a permanent sequence here shouldn't result in any test instability like what was fixed by commit e2933a6. Reviewed-by: Tom Lane Discussion: https://postgr.es/m/ZuOKOut5hhDlf_bP%40nathan Backpatch-through: 12
Backpatch-through: 17 only
When we are building a hash index that is large enough to need pre-sorting (larger than either maintenance_work_mem or NBuffers), the initial sorting phase is interruptible, but the insertion phase wasn't. Add the missing CHECK_FOR_INTERRUPTS(). Per bug #18616 from Alexander Lakhin. Back-patch to all supported branches. Pavel Borisov Discussion: https://postgr.es/m/[email protected]
Reported-by: Nathan Bossart Discussion: https://postgr.es/m/Ztcuwbs0FGCPOEu9@nathan Backpatch-through: 17 only
Also clarify wording. Reported-by: Álvaro Herrera Discussion: https://postgr.es/m/[email protected] Backpatch-through: 17 only
In existing releases of libxml2, xmlXPathCompile can be driven to stack overflow because it fails to protect itself against too-deeply-nested input. While there is an upstream fix as of yesterday, it will take years for that to propagate into all shipping versions. In the meantime, we can protect our own usages basically for free by calling xmlXPathCtxtCompile instead. (The actual bug is that libxml2 keeps its nesting counter in the xmlXPathContext, and its parsing code was willing to just skip counting nesting levels if it didn't have a context. So if we supply a context, all is well. It seems odd actually that it works at all to not supply a context, because this means that XPath parsing does not have access to XML namespace info. Apparently libxml2 never checks namespaces until runtime? Anyway, this seems like good future-proofing even if its only immediate effect is to dodge a bug.) Sadly, this hack only offers protection with libxml2 2.9.11 and newer. Before that there are multiple similar problems, so if you are processing untrusted XML it behooves you to get a newer version. But we have some pretty old libxml2 in the buildfarm, so it seems impractical to add a regression test to verify this fix. Per bug #18617 from Jingzhou Fu. Back-patch to all supported versions. Discussion: https://postgr.es/m/[email protected] Discussion: https://gitlab.gnome.org/GNOME/libxml2/-/issues/799
Reported-by: jian he Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
Commit 5bf748b, which enhanced nbtree ScalarArrayOp execution, made parallel index scans work with the new design for arrays via explicit scheduling of primitive index scans. A backend that successfully scheduled the scan's next primitive index scan saved its backend local array keys in shared memory. Any backend could pick up the scheduled primitive scan within _bt_first. This scheme decouples scheduling a primitive scan from starting the scan (by performing another descent of the index via a _bt_search call from _bt_first) to make things robust. The scheme had a deadlock hazard, at least when the leader process participated in the scan. _bt_parallel_seize had a code path that made backends that were not in an immediate position to start a scheduled primitive index scan wait for some other backend to do so instead. Under the right circumstances, the leader process could wait here forever: the leader would wait for any other backend to start the primitive scan, while every worker was busy waiting on the leader to consume tuples from the scan's tuple queue. To fix, don't wait for a scheduled primitive index scan to be started by some other eligible backend from within _bt_parallel_seize (when the calling backend isn't in a position to do so itself). Return false instead, while recording that the scan has a scheduled primitive index scan in backend local state. This leaves the backend in the same state as the existing case where a backend schedules (or tries to schedule) another primitive index scan from within _bt_advance_array_keys, before calling _bt_parallel_seize. _bt_parallel_seize already handles that case by returning false without waiting, and without unsetting the backend local state. Leaving the backend in this state enables it to start a previously scheduled primitive index scan once it gets back to _bt_first. Oversight in commit 5bf748b, which enhanced nbtree ScalarArrayOp execution. Matthias van de Meent, with tweaks by me. Author: Matthias van de Meent <[email protected]> Reported-By: Tomas Vondra <[email protected]> Reviewed-By: Peter Geoghegan <[email protected]> Discussion: https://postgr.es/m/CAH2-WzmMGaPa32u9x_FvEbPTUkP5e95i=QxR8054nvCRydP-sw@mail.gmail.com Backpatch: 17-, where nbtree SAOP execution was enhanced.
Since we introduced unlogged sequences in v15, identity sequences have defaulted to having the same persistence as their owning table. However, it is possible to change that with ALTER SEQUENCE, and pg_dump tries to preserve the logged-ness of sequences when it doesn't match (as indeed it wouldn't for an unlogged table from before v15). The fly in the ointment is that ALTER SEQUENCE SET [UN]LOGGED fails in binary-upgrade mode, because it needs to assign a new relfilenode which we cannot permit in that mode. Thus, trying to pg_upgrade a database containing a mismatching identity sequence failed. To fix, add syntax to ADD/ALTER COLUMN GENERATED AS IDENTITY to allow the sequence's persistence to be set correctly at creation, and use that instead of ALTER SEQUENCE SET [UN]LOGGED in pg_dump. (I tried to make SET [UN]LOGGED work without any pg_dump modifications, but that seems too fragile to be a desirable answer. This way should be markedly faster anyhow.) In passing, document the previously-undocumented SEQUENCE NAME option that pg_dump also relies on for identity sequences; I see no value in trying to pretend it doesn't exist. Per bug #18618 from Anthony Hsu. Back-patch to v15 where we invented this stuff. Discussion: https://postgr.es/m/[email protected]
Commits 041b968 and 6377e12 changed the interface of scan_analyze_next_block() to take a ReadStream instead of a BlockNumber and a BufferAccessStrategy, and to return a value to indicate when the stream has run out of blocks. This caused integration problems for at least one known extension that uses specially encoded BlockNumber values that map to different underlying storage, because acquire_sample_rows() sets up the stream so that read_stream_next_buffer() reads blocks from the main fork of the relation's SMgrRelation. Provide read_stream_next_block(), as a way for such an extension to access the stream of raw BlockNumbers directly and forward them to its own ReadBuffer() calls after decoding, as it could in earlier releases. The new function returns the BlockNumber and BufferAccessStrategy that were previously passed directly to scan_analyze_next_block(). Alternatively, an extension could wrap the stream of BlockNumbers in another ReadStream with a callback that performs any decoding required to arrive at real storage manager BlockNumber values, so that it could benefit from the I/O combining and concurrency provided by read_stream.c. Another class of table access method that does nothing in scan_analyze_next_block() because it is not block-oriented could use this function to control the number of block sampling loops. It could match the previous behavior with "return read_stream_next_block(stream, &bas) != InvalidBlockNumber". Ongoing work is expected to provide better ANALYZE support for table access methods that don't behave like heapam with respect to storage blocks, but that will be for future releases. Back-patch to 17. Reported-by: Mats Kindahl <[email protected]> Reviewed-by: Mats Kindahl <[email protected]> Discussion: https://postgr.es/m/CA%2B14425%2BCcm07ocG97Fp%2BFrD9xUXqmBKFvecp0p%2BgV2YYR258Q%40mail.gmail.com
This commit adds query ID reports for two code paths when processing extended query protocol messages: - When receiving a bind message, setting it to the first Query retrieved from a cached cache. - When receiving an execute message, setting it to the first PlannedStmt stored in a portal. An advantage of this method is that this is able to cover all the types of portals handled in the extended query protocol, particularly these two when the report done in ExecutorStart() is not enough (neither is an addition in ExecutorRun(), actually, for the second point): - Multiple execute messages, with multiple ExecutorRun(). - Portal with execute/fetch messages, like a query with a RETURNING clause and a fetch size that stores the tuples in a first execute message going though ExecutorStart() and ExecuteRun(), followed by one or more execute messages doing only fetches from the tuplestore created in the first message. This corresponds to the case where execute_is_fetch is set, for example. Note that the query ID reporting done in ExecutorStart() is still necessary, as an EXECUTE requires it. Query ID reporting is optimistic and more calls to pgstat_report_query_id() don't matter as the first report takes priority except if the report is forced. The comment in ExecutorStart() is adjusted to reflect better the reality with the extended query protocol. The test added in pg_stat_statements is a courtesy of Robert Haas. This uses psql's \bind metacommand, hence this part is backpatched down to v16. Reported-by: Kaido Vaikla, Erik Wienhold Author: Sami Imseih Reviewed-by: Jian He, Andrei Lepikhov, Michael Paquier Discussion: https://postgr.es/m/CA+427g8DiW3aZ6pOpVgkPbqK97ouBdf18VLiHFesea2jUk3XoQ@mail.gmail.com Discussion: https://postgr.es/m/CA+TgmoZxtnf_jZ=VqBSyaU8hfUkkwoJCJ6ufy4LGpXaunKrjrg@mail.gmail.com Discussion: https://postgr.es/m/[email protected] Backpatch-through: 14
Doing so caused the leader to hang in wait_event=ParallelFinish, which required an immediate shutdown to resolve. Back-patch to v12 (all supported versions). Francesco Degrassi Discussion: https://postgr.es/m/CAC-SaSzHUKT=vZJ8MPxYdC_URPfax+yoA1hKTcF4ROz_Q6z0_Q@mail.gmail.com
current through 2370582
…nter. The previous documentation stated that num_timed reflects the number of scheduled checkpoints performed. However, checkpoints may be skipped if the server has been idle, and num_timed counts both skipped and completed checkpoints. This commit clarifies the description to make it clear that the counter includes both skipped and completed checkpoints. Back-patch to v17 where pg_stat_checkpointer was added. Author: Fujii Masao Reviewed-by: Alexander Korotkov Discussion: https://postgr.es/m/[email protected]
In print output, there are too many commit links for footnotes in the release notes to be useful. Reported-by: Tom Lane Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
And suppress the symbol in print mode, where the section symbol does not appear. Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
Calling \bind repeatedly would cause the memory allocated for the list of bind parameters to be leaked after each call, as the list is reset when beginning a single call. This issue is fixed by making the cleanup of the bind parameter list more aggressive, refactoring it into a single routine called after processing a query and before running an individual \bind. HEAD required more surgery and has been fixed by 87eeada. Issue introduced by 5b66de3. Reported-by: Anthonin Bonnefoy Discussion: https://postgr.es/m/[email protected] Backpatch-through: 16
Reported-by: Andrew Dunstan Discussion: https://postgr.es/m/[email protected] Author: Andrew Dunstan Backpatch-through: 12
FYI, during PDF builds, this link type generates a "Unresolved ID reference found" warning because it is suppressed from the PDF output. Backpatch-through: 12
Backpatch-through: 12
Make paragraph empty instead of removing it. Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
Commit 5bf748b, which enhanced nbtree ScalarArrayOp execution, made parallel index scans work with the new design for arrays via explicit scheduling of primitive index scans. Under this scheme a parallel index scan with array keys will perform the same number of index descents as an equivalent serial index scan (barring corner cases where an individual parallel worker discovers that it can advance the scan's array keys without anybody needing to perform another descent of the index to get to the relevant page on the leaf level). Despite all this, the pgstats accounting wasn't updated; it continued to increment the total number of index scans for the rel once per _bt_first call, no matter the details. As a result, the number of (primitive) index scans could be over-counted during parallel scans. To fix, delay incrementing the count of index scans until after we've established that another descent of the index (using either _bt_search or _bt_endpoint) is required. That way pg_stat_user_tables.idx_scan always advances in the same way, regardless of whether or not the scan makes use of parallelism. Oversight in commit 5bf748b, which enhanced nbtree ScalarArrayOp execution. Author: Peter Geoghegan <[email protected]> Reviewed-By: Tomas Vondra <[email protected]> Discussion: https://postgr.es/m/CAH2-Wz=E7XrkvscBN0U6V81NK3Q-dQOmivvbEsjG-zwEfDdFpg@mail.gmail.com Discussion: https://postgr.es/m/CAH2-WzkRqvaqR2CTNqTZP0z6FuL4-3ED6eQB0yx38XBNj1v-4Q@mail.gmail.com Backpatch: 17-, where nbtree SAOP execution was enhanced.
This has always been possible, but the syntax is a bit obscure, and our user-facing docs were not very helpful. Spell it out more clearly. Per complaint from Dominique Devienne. Back-patch to all supported branches. Discussion: https://postgr.es/m/CAFCRh-8JNEy+dV4SXFOrWca50u+d=--TO4cq=+ac1oBtfJy4AA@mail.gmail.com
Reported-by: Tom Lane Discussion: https://postgr.es/m/[email protected] Author: Jonathan Katz Backpatch-through: 17 only
Also some trivial copy-editing.
Source-Git-URL: https://git.postgresql.org/git/pgtranslation/messages.git Source-Git-Hash: 4b069f67b5be4227eb620a74c9900f079f2e59f4
doc_ja_16の最新をフォワードポートしました（2024-09-26）。
KenichiroTanaka
approved these changes
Sep 27, 2024
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#3088 のREL_17_0のマージ後にマージされる想定です。