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* Fix misbehavior of EvalPlanQual checks with multiple result relations.Tom Lane2023-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The idea of EvalPlanQual is that we replace the query's scan of the result relation with a single injected tuple, and see if we get a tuple out, thereby implying that the injected tuple still passes the query quals. (In join cases, other relations in the query are still scanned normally.) This logic was not updated when commit 86dc90056 made it possible for a single DML query plan to have multiple result relations, when the query target relation has inheritance or partition children. We replaced the output for the current result relation successfully, but other result relations were still scanned normally; thus, if any other result relation contained a tuple satisfying the quals, we'd think the EPQ check passed, even if it did not pass for the injected tuple itself. This would lead to update or delete actions getting performed when they should have been skipped due to a conflicting concurrent update in READ COMMITTED isolation mode. Fix by blocking all sibling result relations from emitting tuples during an EvalPlanQual recheck. In the back branches, the fix is complicated a bit by the need to not change the size of struct EPQState (else we'd have ABI-breaking changes in offsets in struct ModifyTableState). Like the back-patches of 3f7836ff6 and 4b3e37993, add a separately palloc'd struct to avoid that. The logic is the same as in HEAD otherwise. This is only a live bug back to v14 where 86dc90056 came in. However, I chose to back-patch the test cases further, on the grounds that this whole area is none too well tested. I skipped doing so in v11 though because none of the test applied cleanly, and it didn't quite seem worth extra work for a branch with only six months to live. Per report from Ante Krešić (via Aleksander Alekseev) Discussion: https://postgr.es/m/CAJ7c6TMBTN3rcz4=AjYhLPD_w3FFT0Wq_C15jxCDn8U4tZnH1g@mail.gmail.com
* Allocate hash join files in a separate memory contextTomas Vondra2023-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | Should a hash join exceed memory limit, the hashtable is split up into multiple batches. The number of batches is doubled each time a given batch is determined not to fit in memory. Each batch file is allocated with a block-sized buffer for buffering tuples and parallel hash join has additional sharedtuplestore accessor buffers. In some pathological cases requiring a lot of batches, often with skewed data, bad stats, or very large datasets, users can run out-of-memory solely from the memory overhead of all the batch files' buffers. Batch files were allocated in the ExecutorState memory context, making it very hard to identify when this batch explosion was the source of an OOM. This commit allocates the batch files in a dedicated memory context, making it easier to identify the cause of an OOM and work to avoid it. Based on initial draft by Tomas Vondra, with significant reworks and improvements by Jehan-Guillaume de Rorthais. Author: Jehan-Guillaume de Rorthais <jgdr@dalibo.com> Author: Tomas Vondra <tomas.vondra@enterprisedb.com> Reviewed-by: Melanie Plageman <melanieplageman@gmail.com> Discussion: https://postgr.es/m/20190421114618.z3mpgmimc3rmubi4@development Discussion: https://postgr.es/m/20230504193006.1b5b9622%40karst#273020ff4061fc7a2fbb1ba96b281f17
* Describe hash join implementationTomas Vondra2023-05-19
| | | | | | | | | | Add a high level description of our implementation of the hybrid hash join algorithm to the block comment in nodeHashjoin.c. Author: Melanie Plageman <melanieplageman@gmail.com> Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com> Reviewed-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com> Discussion: https://postgr.es/m/20230516160051.4267a800%40karst
* Remove stray mid-sentence tabs in commentsPeter Eisentraut2023-05-19
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* Add back SQLValueFunction for SQL keywordsMichael Paquier2023-05-17
| | | | | | | | | | | | | | | | | | | | | | | | This is equivalent to a revert of f193883 and fb32748, with the addition that the declaration of the SQLValueFunction node needs to gain a couple of node_attr for query jumbling. The performance impact of removing the function call inlining is proving to be too huge for some workloads where these are used. A worst-case test case of involving only simple SELECT queries with a SQL keyword is proving to lead to a reduction of 10% in TPS via pgbench and prepared queries on a high-end machine. None of the tests I ran back for this set of changes saw such a huge gap, but Alexander Lakhin and Andres Freund have found that this can be noticeable. Keeping the older performance would mean to do more inlining in the executor when using COERCE_SQL_SYNTAX for a function expression, similarly to what SQLValueFunction does. This requires more redesign work and there is little time until 16beta1 is released, so for now reverting the change is the best way forward, bringing back the previous performance. Bump catalog version. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/b32bed1b-0746-9b20-1472-4bdc9ca66d52@gmail.com
* Mark internal messages as no longer translatableAlvaro Herrera2023-05-16
| | | | | | | | | | | The problem that these messages protect against can only occur because a corrupted hash spill file was written, i.e., a Postgres bug. There's no reason to have them as translatable. Backpatch to 15, where these messages were changed by commit c4649cce39a4. Reviewed-by: Daniel Gustafsson <daniel@yesql.se> Discussion: https://postgr.es/m/20230510175407.dwa5v477pw62ikyx@alvherre.pgsql
* Fix ExecCheckPermissions call in RI_Initial_CheckAlvaro Herrera2023-05-04
| | | | | | | | | | | | | | | | | | RI_Initial_Check was setting up a list of RTEPermissionInfo for ExecCheckPermissions() wrong, and the problem is subtle enough that it doesn't have any immediate effect in core code. However, if an extension is using the ExecutorCheckPerms_hook, then it would get the wrong parameters and perhaps arrive at a wrong conclusion, or outright malfunction. Fix by constructing that list and the RTE list more honestly. We also add an assertion check to verify that these lists match. This new assertion would have caught this bug. Co-authored-by: Олег Целебровский (Oleg Tselebrovskii) <o.tselebrovskiy@postgrespro.ru> Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Amit Langote <amitlangote09@gmail.com> Discussion: https://postgr.es/m/3722b7a2cbe27a1796ee40824bd86dd1@postgrespro.ru
* Revert "Move PartitionPruneInfo out of plan nodes into PlannedStmt"Alvaro Herrera2023-05-04
| | | | | | | | | | | | | This reverts commit ec386948948c and its fixup 589bb816499e. This change was intended to support query planning avoiding acquisition of locks on partitions that were going to be pruned; however, the overall project took a different direction at [1] and this bit is no longer needed. Put things back the way they were as agreed in [2], to avoid unnecessary complexity. Discussion: [1] https://postgr.es/m/4191508.1674157166@sss.pgh.pa.us Discussion: [2] https://postgr.es/m/20230502175409.kcoirxczpdha26wt@alvherre.pgsql
* Fix typos in commentsMichael Paquier2023-05-02
| | | | | | | | | The changes done in this commit impact comments with no direct user-visible changes, with fixes for incorrect function, variable or structure names. Author: Alexander Lakhin Discussion: https://postgr.es/m/e8c38840-596a-83d6-bd8d-cebc51111572@gmail.com
* Fix buffer refcount leak with FDW bulk insertsMichael Paquier2023-04-25
| | | | | | | | | | | | | | | | | | | | | The leak would show up when using batch inserts with foreign tables included in a partition tree, as the slots used in the batch were not reset once processed. In order to fix this problem, some ExecClearTuple() are added to clean up the slots used once a batch is filled and processed, mapping with the number of slots currently in use as tracked by the counter ri_NumSlots. This buffer refcount leak has been introduced in b676ac4 with the addition of the executor facility to improve bulk inserts for FDWs, so backpatch down to 14. Alexander has provided the patch (slightly modified by me). The test for postgres_fdw comes from me, based on the test case that the author has sent in the report. Author: Alexander Pyhalov Discussion: https://postgr.es/m/b035780a740efd38dc30790c76927255@postgrespro.ru Backpatch-through: 14
* Rename ExecAggTransReparent, and improve its documentation.Tom Lane2023-04-24
| | | | | | | | | | | | | The name of this function suggests that it ought to reparent R/W expanded objects to be children of the persistent aggcontext, instead of copying them. In fact it does no such thing, and if you try to make it do so you will see multiple regression failures. Rename it to the less-misleading ExecAggCopyTransValue, and add commentary about why that attractive-sounding optimization won't work. Also adjust comments at call sites, some of which were describing logic that has since been moved into ExecAggCopyTransValue. Discussion: https://postgr.es/m/3004282.1681930251@sss.pgh.pa.us
* Fix various typos and incorrect/outdated name referencesDavid Rowley2023-04-19
| | | | | Author: Alexander Lakhin Discussion: https://postgr.es/m/699beab4-a6ca-92c9-f152-f559caf6dc25@gmail.com
* Fix various typosDavid Rowley2023-04-18
| | | | | | | | | | | | This fixes many spelling mistakes in comments, but a few references to invalid parameter names, function names and option names too in comments and also some in string constants Also, fix an #undef that was undefining the incorrect definition Author: Alexander Lakhin Reviewed-by: Justin Pryzby Discussion: https://postgr.es/m/d5f68d19-c0fc-91a9-118d-7c6a5a3f5fad@gmail.com
* Ensure result of an aggregate's finalfunc is made read-only.Tom Lane2023-04-16
| | | | | | | | | | | | | | | The finalfunc might return a read-write expanded object. If we de-duplicate multiple call sites for the aggregate, any function(s) receiving the aggregate result earlier could alter or destroy the value that reaches the ones called later. This is a brown-paper-bag bug in commit 42b746d4c, because we actually considered the need for read-only-ness but failed to realize that it applied to the case with a finalfunc as well as the case without. Per report from Justin Pryzby. New error in HEAD, no need for back-patch. Discussion: https://postgr.es/m/ZDm5TuKsh3tzoEjz@telsasoft.com
* Fix assignment to array of domain over composite, redux.Tom Lane2023-04-15
| | | | | | | | | | | | | | | | Commit 3e310d837 taught isAssignmentIndirectionExpr() to look through CoerceToDomain nodes. That's not sufficient, because since commit 04fe805a1 it's been possible for the planner to simplify CoerceToDomain to RelabelType when the domain has no constraints to enforce. So we need to look through RelabelType too. Per bug #17897 from Alexander Lakhin. Although 3e310d837 was back-patched to v11, it seems sufficient to apply this change to v12 and later, since 04fe805a1 came in in v12. Dmitry Dolgov Discussion: https://postgr.es/m/17897-4216c546c3874044@postgresql.org
* Fix PHJ match bit initialization.Thomas Munro2023-04-14
| | | | | | | | | | | | | | | | | Hash join tuples reuse the HOT status bit to indicate match status during hash join execution. Correct reuse requires clearing the bit in all tuples. Serial hash join and parallel multi-batch hash join do so upon inserting the tuple into the hashtable. Single batch parallel hash join and batch 0 of unexpected multi-batch hash joins forgot to do this. It hadn't come up before because hashtable tuple match bits are only used for right and full outer joins and parallel ROJ and FOJ were unsupported. 11c2d6fdf5 introduced support for parallel ROJ/FOJ but neglected to ensure the match bits were reset. Author: Melanie Plageman <melanieplageman@gmail.com> Reported-by: Richard Guo <guofenglinux@gmail.com> Discussion: https://postgr.es/m/flat/CAMbWs48Nde1Mv%3DBJv6_vXmRKHMuHZm2Q_g4F6Z3_pn%2B3EV6BGQ%40mail.gmail.com
* Remove overzealous assertion from PHJ.Thomas Munro2023-04-13
| | | | | | | | | | | | | | We can't assert that we're the only process attached to a barrier after BarrierArriveAndDetachExceptLast(). Although that'll be true almost always, a late-starting parallel worker can attach very briefly (that is, immediately detach after checking the phase) right at that moment. BarrierArriveAndDetachExceptLast() already contains an assertion like that, but it holds a spinlock preventing the race. This thinko caused a one-off failure on build farm animal chimaera. Diagnosed-by: Melanie Plageman <melanieplageman@gmail.com> Reported-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/3590249.1680971629@sss.pgh.pa.us
* Fix row tracking in pg_stat_statements with extended query protocolMichael Paquier2023-04-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pg_stat_statements relies on EState->es_processed to count the number of rows processed by ExecutorRun(). This proves to be a problem under the extended query protocol when the result of a query is fetched through more than one call of ExecutorRun(), as es_processed is reset each time ExecutorRun() is called. This causes pg_stat_statements to report the number of rows calculated in the last execute fetch, rather than the global sum of all the rows processed. As pquery.c tells, this is a problem when a portal does not use holdStore. For example, DMLs with RETURNING would report a correct tuple count as these do one execution cycle when the query is first executed to fill in the portal's store with one ExecutorRun(), feeding on the portal's store for each follow-up execute fetch depending on the fetch size requested by the client. The fix proposed for this issue is simple with the addition of an extra counter in EState that's preserved across multiple ExecutorRun() calls, incremented with the value calculated in es_processed. This approach is not back-patchable, unfortunately. Note that libpq does not currently give any way to control the fetch size when using the extended v3 protocol, meaning that in-core testing is not possible yet. This issue can be easily verified with the JDBC driver, though, with *autocommit disabled*. Hence, having in-core tests requires more features, left for future discussion: - At least two new libpq routines splitting PQsendQueryGuts(), one for the bind/describe and a second for a series of execute fetches with a custom fetch size, likely in a fashion similar to what JDBC does. - A psql meta-command for the execute phase. This part is not strictly mandatory, still it could be handy. Reported-by: Andrew Dunstan (original discovery by Simon Siggs) Author: Sami Imseih Reviewed-by: Tom Lane, Michael Paquier Discussion: https://postgr.es/m/EBE6C507-9EB6-4142-9E4D-38B1673363A7@amazon.com Discussion: https://postgr.es/m/c90890e7-9c89-c34f-d3c5-d5c763a34bd8@dunslane.net
* Support "Right Anti Join" plan shapes.Tom Lane2023-04-05
| | | | | | | | | | | | | Merge and hash joins can support antijoin with the non-nullable input on the right, using very simple combinations of their existing logic for right join and anti join. This gives the planner more freedom about how to order the join. It's particularly useful for hash join, since we may now have the option to hash the smaller table instead of the larger. Richard Guo, reviewed by Ronan Dunklau and myself Discussion: https://postgr.es/m/CAMbWs48xh9hMzXzSy3VaPzGAz+fkxXXTUbCLohX1_L8THFRm2Q@mail.gmail.com
* Revert 764da7710bAlexander Korotkov2023-04-03
| | | | Discussion: https://postgr.es/m/20230323003003.plgaxjqahjgkuxrk%40awork3.anarazel.de
* Revert 11470f544eAlexander Korotkov2023-04-03
| | | | Discussion: https://postgr.es/m/20230323003003.plgaxjqahjgkuxrk%40awork3.anarazel.de
* SQL/JSON: support the IS JSON predicateAlvaro Herrera2023-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces the SQL standard IS JSON predicate. It operates on text and bytea values representing JSON, as well as on the json and jsonb types. Each test has IS and IS NOT variants and supports a WITH UNIQUE KEYS flag. The tests are: IS JSON [VALUE] IS JSON ARRAY IS JSON OBJECT IS JSON SCALAR These should be self-explanatory. The WITH UNIQUE KEYS flag makes these return false when duplicate keys exist in any object within the value, not necessarily directly contained in the outermost object. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Author: Andrew Dunstan <andrew@dunslane.net> Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby. Discussion: https://postgr.es/m/CAF4Au4w2x-5LTnN_bxky-mq4=WOqsGsxSpENCzHRAzSnEd8+WQ@mail.gmail.com Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
* Move ExecEvalJsonConstructor new function to a more natural placeAlvaro Herrera2023-03-31
| | | | | Commit 7081ac46ace8 put it at the end of the file, but that doesn't look very nice.
* Parallel Hash Full Join.Thomas Munro2023-03-31
| | | | | | | | | | | | | | | | | | | | | | | | | | Full and right outer joins were not supported in the initial implementation of Parallel Hash Join because of deadlock hazards (see discussion). Therefore FULL JOIN inhibited parallelism, as the other join strategies can't do that in parallel either. Add a new PHJ phase PHJ_BATCH_SCAN that scans for unmatched tuples on the inner side of one batch's hash table. For now, sidestep the deadlock problem by terminating parallelism there. The last process to arrive at that phase emits the unmatched tuples, while others detach and are free to go and work on other batches, if there are any, but otherwise they finish the join early. That unfairness is considered acceptable for now, because it's better than no parallelism at all. The build and probe phases are run in parallel, and the new scan-for-unmatched phase, while serial, is usually applied to the smaller of the two relations and is either limited by some multiple of work_mem, or it's too big and is partitioned into batches and then the situation is improved by batch-level parallelism. Author: Melanie Plageman <melanieplageman@gmail.com> Author: Thomas Munro <thomas.munro@gmail.com> Reviewed-by: Thomas Munro <thomas.munro@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKG%2BA6ftXPz4oe92%2Bx8Er%2BxpGZqto70-Q_ERwRaSyA%3DafNg%40mail.gmail.com
* Fix inconsistencies and style issues in new SQL/JSON codeAlvaro Herrera2023-03-30
| | | | | | Reported by Alexander Lakhin. Discussion: https://postgr.es/m/60483139-5c34-851d-baee-6c0d014e1710@gmail.com
* Fix outdated comments regarding TupleTableSlotsDavid Rowley2023-03-30
| | | | | | | | | | | | The tts_flag is named TTS_FLAG_SHOULDFREE, so use that instead of TTS_SHOULDFREE, which is the name of the macro that checks for that flag. Additionally, 4da597edf got rid of the TupleTableSlot.tts_tuple field but forgot to update a comment which referenced that field. Fix that. Reported-by: Zhen Mingyang <zhenmingyang@yeah.net> Reported-by: Richard Guo <guofenglinux@gmail.com> Discussion: https://postgr.es/m/1a96696c.9d3.187193989c3.Coremail.zhenmingyang@yeah.net
* SQL/JSON: add standard JSON constructor functionsAlvaro Herrera2023-03-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commit introduces the SQL/JSON standard-conforming constructors for JSON types: JSON_ARRAY() JSON_ARRAYAGG() JSON_OBJECT() JSON_OBJECTAGG() Most of the functionality was already present in PostgreSQL-specific functions, but these include some new functionality such as the ability to skip or include NULL values, and to allow duplicate keys or throw error when they are found, as well as the standard specified syntax to specify output type and format. Author: Nikita Glukhov <n.gluhov@postgrespro.ru> Author: Teodor Sigaev <teodor@sigaev.ru> Author: Oleg Bartunov <obartunov@gmail.com> Author: Alexander Korotkov <aekorotkov@gmail.com> Author: Amit Langote <amitlangote09@gmail.com> Reviewers have included (in no particular order) Andres Freund, Alexander Korotkov, Pavel Stehule, Andrew Alsup, Erik Rijkers, Zihong Yu, Himanshu Upadhyaya, Daniel Gustafsson, Justin Pryzby. Discussion: https://postgr.es/m/CAF4Au4w2x-5LTnN_bxky-mq4=WOqsGsxSpENCzHRAzSnEd8+WQ@mail.gmail.com Discussion: https://postgr.es/m/cd0bb935-0158-78a7-08b5-904886deac4b@postgrespro.ru Discussion: https://postgr.es/m/20220616233130.rparivafipt6doj3@alap3.anarazel.de Discussion: https://postgr.es/m/abd9b83b-aa66-f230-3d6d-734817f0995d%40postgresql.org
* Simplify useless 0L constantsPeter Eisentraut2023-03-29
| | | | | | | In ancient times, these belonged to arguments or fields that were actually of type long, but now they are not anymore, so this "L" decoration is just confusing. (Some other 0L and other "L" constants remain, where they are actually associated with a long type.)
* Fix oversights in array manipulation.Tom Lane2023-03-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The nested-arrays code path in ExecEvalArrayExpr() used palloc to allocate the result array, whereas every other array-creating function has used palloc0 since 18c0b4ecc. This mostly works, but unused bits past the end of the nulls bitmap may end up undefined. That causes valgrind complaints with -DWRITE_READ_PARSE_PLAN_TREES, and could cause planner misbehavior as cited in 18c0b4ecc. There seems no very good reason why we should strive to avoid palloc0 in just this one case, so fix it the easy way with s/palloc/palloc0/. While looking at that I noted that we also failed to check for overflow of "nbytes" and "nitems" while summing the sizes of the sub-arrays, potentially allowing a crash due to undersized output allocation. For "nbytes", follow the policy used by other array-munging code of checking for overflow after each addition. (As elsewhere, the last addition of the array's overhead space doesn't need an extra check, since palloc itself will catch a value between 1Gb and 2Gb.) For "nitems", there's no very good reason to sum the inputs at all, since we can perfectly well use ArrayGetNItems' result instead of ignoring it. Per discussion of this bug, also remove redundant zeroing of the nulls bitmap in array_set_element and array_set_slice. Patch by Alexander Lakhin and myself, per bug #17858 from Alexander Lakhin; thanks also to Richard Guo. These bugs are a dozen years old, so back-patch to all supported branches. Discussion: https://postgr.es/m/17858-8fd287fd3663d051@postgresql.org
* Add SysCacheGetAttrNotNull for guaranteed not-null attrsDaniel Gustafsson2023-03-25
| | | | | | | | | | | | | When extracting an attr from a cached tuple in the syscache with SysCacheGetAttr the isnull parameter must be checked in case the attr cannot be NULL. For cases when this is known beforehand, a wrapper is introduced which perform the errorhandling internally on behalf of the caller, invoking an elog in case of a NULL attr. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/AD76405E-DB45-46B6-941F-17B1EB3A9076@yesql.se
* Invent GENERIC_PLAN option for EXPLAIN.Tom Lane2023-03-24
| | | | | | | | | | | | | | | | | This provides a very simple way to see the generic plan for a parameterized query. Without this, it's necessary to define a prepared statement and temporarily change plan_cache_mode, which is a bit tedious. One thing that's a bit of a hack perhaps is that we disable execution-time partition pruning when the GENERIC_PLAN option is given. That's because the pruning code may attempt to fetch the value of one of the parameters, which would fail. Laurenz Albe, reviewed by Julien Rouhaud, Christoph Berg, Michel Pelletier, Jim Jones, and myself Discussion: https://postgr.es/m/0a29b954b10b57f0d135fe12aa0909bd41883eb0.camel@cybertec.at
* Ignore generated columns during apply of update/delete.Amit Kapila2023-03-23
| | | | | | | | | | | | We fail to apply updates and deletes when the REPLICA IDENTITY FULL is used for the table having generated columns. We didn't use to ignore generated columns while doing tuple comparison among the tuples from the publisher and subscriber during apply of updates and deletes. Author: Onder Kalaci Reviewed-by: Shi yu, Amit Kapila Backpatch-through: 12 Discussion: https://postgr.es/m/CACawEhVQC9WoofunvXg12aXtbqKnEgWxoRx3+v8q32AWYsdpGg@mail.gmail.com
* Improve the naming of Parallel Hash Join phases.Thomas Munro2023-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | * Commit 3048898e dropped -ING from PHJ wait event names. Update the corresponding barrier phases names to match. * Rename the "DONE" phases to "FREE". That's symmetrical with "ALLOCATE", and names the activity that actually happens in that phase (as we do for the other phases) rather than a state. The bug fixed by commit 8d578b9b might have been more obvious with this name. * Rename the batch/bucket growth barriers' "ALLOCATE" phases to "REALLOCATE", a better description of what they do. * Update the high level comments about phases to highlight phases are executed by a single process with an asterisk (mostly memory management phases). No behavior change, as this is just improving internal identifiers. The only user-visible sign of this is that a couple of wait events' display names change from "...Allocate" to "...Reallocate" in pg_stat_activity, to stay in sync with the internal names. Reviewed-by: Melanie Plageman <melanieplageman@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKG%2BMDpwF2Eo2LAvzd%3DpOh81wUTsrwU1uAwR-v6OGBB6%2B7g%40mail.gmail.com
* Allow locking updated tuples in tuple_update() and tuple_delete()Alexander Korotkov2023-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently, in read committed transaction isolation mode (default), we have the following sequence of actions when tuple_update()/tuple_delete() finds the tuple updated by concurrent transaction. 1. Attempt to update/delete tuple with tuple_update()/tuple_delete(), which returns TM_Updated. 2. Lock tuple with tuple_lock(). 3. Re-evaluate plan qual (recheck if we still need to update/delete and calculate the new tuple for update). 4. Second attempt to update/delete tuple with tuple_update()/tuple_delete(). This attempt should be successful, since the tuple was previously locked. This patch eliminates step 2 by taking the lock during first tuple_update()/tuple_delete() call. Heap table access method saves some efforts by checking the updated tuple once instead of twice. Future undo-based table access methods, which will start from the latest row version, can immediately place a lock there. The code in nodeModifyTable.c is simplified by removing the nested switch/case. Discussion: https://postgr.es/m/CAPpHfdua-YFw3XTprfutzGp28xXLigFtzNbuFY8yPhqeq6X5kg%40mail.gmail.com Reviewed-by: Aleksander Alekseev, Pavel Borisov, Vignesh C, Mason Sharp Reviewed-by: Andres Freund, Chris Travers
* Evade extra table_tuple_fetch_row_version() in ExecUpdate()/ExecDelete()Alexander Korotkov2023-03-23
| | | | | | | | | | | When we lock tuple using table_tuple_lock() then we at the same time fetch the locked tuple to the slot. In this case we can skip extra table_tuple_fetch_row_version() thank to we've already fetched the 'old' tuple and nobody can change it concurrently since it's locked. Discussion: https://postgr.es/m/CAPpHfdua-YFw3XTprfutzGp28xXLigFtzNbuFY8yPhqeq6X5kg%40mail.gmail.com Reviewed-by: Aleksander Alekseev, Pavel Borisov, Vignesh C, Mason Sharp Reviewed-by: Andres Freund, Chris Travers
* Ignore dropped columns during apply of update/delete.Amit Kapila2023-03-21
| | | | | | | | | | | We fail to apply updates and deletes when the REPLICA IDENTITY FULL is used for the table having dropped columns. We didn't use to ignore dropped columns while doing tuple comparison among the tuples from the publisher and subscriber during apply of updates and deletes. Author: Onder Kalaci, Shi yu Reviewed-by: Amit Kapila Discussion: https://postgr.es/m/CACawEhVQC9WoofunvXg12aXtbqKnEgWxoRx3+v8q32AWYsdpGg@mail.gmail.com
* Fix race in parallel hash join batch cleanup, take II.Thomas Munro2023-03-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With unlucky timing and parallel_leader_participation=off (not the default), PHJ could attempt to access per-batch shared state just as it was being freed. There was code intended to prevent that by checking for a cleared pointer, but it was racy. Fix, by introducing an extra barrier phase. The new phase PHJ_BUILD_RUNNING means that it's safe to access the per-batch state to find a batch to help with, and PHJ_BUILD_DONE means that it is too late. The last to detach will free the array of per-batch state as before, but now it will also atomically advance the phase, so that late attachers can avoid the hazard. This mirrors the way per-batch hash tables are freed (see phases PHJ_BATCH_PROBING and PHJ_BATCH_DONE). An earlier attempt to fix this (commit 3b8981b6, later reverted) missed one special case. When the inner side is empty (the "empty inner optimization), the build barrier would only make it to PHJ_BUILD_HASHING_INNER phase before workers attempted to detach from the hashtable. In that case, fast-forward the build barrier to PHJ_BUILD_RUNNING before proceeding, so that our later assertions hold and we can still negotiate who is cleaning up. Revealed by build farm failures, where BarrierAttach() failed a sanity check assertion, because the memory had been clobbered by dsa_free(). In non-assert builds, the result could be a segmentation fault. Back-patch to all supported releases. Author: Thomas Munro <thomas.munro@gmail.com> Author: Melanie Plageman <melanieplageman@gmail.com> Reported-by: Michael Paquier <michael@paquier.xyz> Reported-by: David Geier <geidav.pg@gmail.com> Tested-by: David Geier <geidav.pg@gmail.com> Discussion: https://postgr.es/m/20200929061142.GA29096%40paquier.xyz
* Ignore BRIN indexes when checking for HOT updatesTomas Vondra2023-03-20
| | | | | | | | | | | | | | | | | | | | | | | | When determining whether an index update may be skipped by using HOT, we can ignore attributes indexed by block summarizing indexes without references to individual tuples that need to be cleaned up. A new type TU_UpdateIndexes provides a signal to the executor to determine which indexes to update - no indexes, all indexes, or only the summarizing indexes. This also removes rd_indexattr list, and replaces it with rd_attrsvalid flag. The list was not used anywhere, and a simple flag is sufficient. This was originally committed as 5753d4ee32, but then got reverted by e3fcca0d0d because of correctness issues. Original patch by Josef Simanek, various fixes and improvements by Tomas Vondra and me. Authors: Matthias van de Meent, Josef Simanek, Tomas Vondra Reviewed-by: Tomas Vondra, Alvaro Herrera Discussion: https://postgr.es/m/05ebcb44-f383-86e3-4f31-0a97a55634cf@enterprisedb.com Discussion: https://postgr.es/m/CAFp7QwpMRGcDAQumN7onN9HjrJ3u4X3ZRXdGFT0K5G2JWvnbWg%40mail.gmail.com
* Fix memory leak in Memoize cache key evaluationDavid Rowley2023-03-20
| | | | | | | | | | | | | | | | | | When probing the Memoize cache to check if the current cache key values exist in the cache, we perform an evaluation of the expressions making up the cache key before probing the hash table for those values. This operation could leak memory as it is possible that the cache key is an expression which requires allocation of memory, as was the case in bug 17844. Here we fix this by correctly switching to the per tuple context before evaluating the cache expressions so that the memory is freed next time the per tuple context is reset. Bug: 17844 Reported-by: Alexey Ermakov Discussion: https://postgr.es/m/17844-d2f6f9e75a622bed@postgresql.org Backpatch-through: 14, where Memoize was introduced
* Support [NO] INDENT option in XMLSERIALIZE().Tom Lane2023-03-15
| | | | | | | | | | | | | | This adds the ability to pretty-print XML documents ... according to libxml's somewhat idiosyncratic notions of what's pretty, anyway. One notable divergence from a strict reading of the spec is that libxml is willing to collapse empty nodes "<node></node>" to just "<node/>", whereas SQL and the underlying XML spec say that this option should only result in whitespace tweaks. Nonetheless, it seems close enough to justify using the SQL-standard syntax. Jim Jones, reviewed by Peter Smith and myself Discussion: https://postgr.es/m/2f5df461-dad8-6d7d-4568-08e10608a69b@uni-muenster.de
* Allow the use of indexes other than PK and REPLICA IDENTITY on the subscriber.Amit Kapila2023-03-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Using REPLICA IDENTITY FULL on the publisher can lead to a full table scan per tuple change on the subscription when REPLICA IDENTITY or PK index is not available. This makes REPLICA IDENTITY FULL impractical to use apart from some small number of use cases. This patch allows using indexes other than PRIMARY KEY or REPLICA IDENTITY on the subscriber during apply of update/delete. The index that can be used must be a btree index, not a partial index, and it must have at least one column reference (i.e. cannot consist of only expressions). We can uplift these restrictions in the future. There is no smart mechanism to pick the index. If there is more than one index that satisfies these requirements, we just pick the first one. We discussed using some of the optimizer's low-level APIs for this but ruled it out as that can be a maintenance burden in the long run. This patch improves the performance in the vast majority of cases and the improvement is proportional to the amount of data in the table. However, there could be some regression in a small number of cases where the indexes have a lot of duplicate and dead rows. It was discussed that those are mostly impractical cases but we can provide a table or subscription level option to disable this feature if required. Author: Onder Kalaci, Amit Kapila Reviewed-by: Peter Smith, Shi yu, Hou Zhijie, Vignesh C, Kuroda Hayato, Amit Kapila Discussion: https://postgr.es/m/CACawEhVLqmAAyPXdHEPv1ssU2c=dqOniiGz7G73HfyS7+nGV4w@mail.gmail.com
* Fix MERGE command tag for actions blocked by BEFORE ROW triggers.Dean Rasheed2023-03-13
| | | | | | | | | | | | This ensures that the row count in the command tag for a MERGE is correctly computed in the case where UPDATEs or DELETEs are skipped due to a BEFORE ROW trigger returning NULL (the INSERT case was already handled correctly by ExecMergeNotMatched() calling ExecInsert()). Back-patch to v15, where MERGE was introduced. Discussion: https://postgr.es/m/CAEZATCU8XEmR0JWKDtyb7iZ%3DqCffxS9uyJt0iOZ4TV4RT%2Bow1w%40mail.gmail.com
* Fix concurrent update issues with MERGE.Dean Rasheed2023-03-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If MERGE attempts an UPDATE or DELETE on a table with BEFORE ROW triggers, or a cross-partition UPDATE (with or without triggers), and a concurrent UPDATE or DELETE happens, the merge code would fail. In some cases this would lead to a crash, while in others it would cause the wrong merge action to be executed, or no action at all. The immediate cause of the crash was the trigger code calling ExecGetUpdateNewTuple() as part of the EPQ mechanism, which fails because during a merge ri_projectNew is NULL, since merge has its own per-action projection information, which ExecGetUpdateNewTuple() knows nothing about. Fix by arranging for the trigger code to exit early, returning the TM_Result and TM_FailureData information, if a concurrent modification is detected, allowing the merge code to do the necessary EPQ handling in its own way. Similarly, prevent the cross-partition update code from doing any EPQ processing for a merge, allowing the merge code to work out what it needs to do. This leads to a number of simplifications in nodeModifyTable.c. Most notably, the ModifyTableContext->GetUpdateNewTuple() callback is no longer needed, and mergeGetUpdateNewTuple() can be deleted, since there is no longer any requirement for get-update-new-tuple during a merge. Similarly, ModifyTableContext->cpUpdateRetrySlot is no longer needed. Thus ExecGetUpdateNewTuple() and the retry_slot handling of ExecCrossPartitionUpdate() can be restored to how they were in v14, before the merge code was added, and ExecMergeMatched() no longer needs any special-case handling for cross-partition updates. While at it, tidy up ExecUpdateEpilogue() a bit, making it handle recheckIndexes locally, rather than passing it in as a parameter, ensuring that it is freed properly. This dates back to when it was split off from ExecUpdate() to support merge. Per bug #17809 from Alexander Lakhin, and follow-up investigation of bug #17792, also from Alexander Lakhin. Back-patch to v15, where MERGE was introduced, taking care to preserve backwards-compatibility of the trigger API in v15 for any extensions that might use it. Discussion: https://postgr.es/m/17809-9e6650bef133f0fe%40postgresql.org https://postgr.es/m/17792-0f89452029662c36%40postgresql.org
* Fix some more cases of missed GENERATED-column updates.Tom Lane2023-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | If UPDATE is forced to retry after an EvalPlanQual check, it neglected to repeat GENERATED-column computations, even though those might well have changed since we're dealing with a different tuple than before. Fixing this is mostly a matter of looping back a bit further when we retry. In v15 and HEAD that's most easily done by altering the API of ExecUpdateAct so that it includes computing GENERATED expressions. Also, if an UPDATE in a partitioned table turns into a cross-partition INSERT operation, we failed to recompute GENERATED columns. That's a bug since 8bf6ec3ba allowed partitions to have different generation expressions; although it seems to have no ill effects before that. Fixing this is messier because we can now have situations where the same query needs both the UPDATE-aligned set of GENERATED columns and the INSERT-aligned set, and it's unclear which set will be generated first (else we could hack things by forcing the INSERT-aligned set to be generated, which is indeed how fe9e658f4 made it work for MERGE). The best fix seems to be to build and store separate sets of expressions for the INSERT and UPDATE cases. That would create ABI issues in the back branches, but so far it seems we can leave this alone in the back branches. Per bug #17823 from Hisahiro Kauchi. The first part of this affects all branches back to v12 where GENERATED columns were added. Discussion: https://postgr.es/m/17823-b64909cf7d63de84@postgresql.org
* Fill EState.es_rteperminfos more systematically.Tom Lane2023-03-06
| | | | | | | | | | | | | | | | | | While testing a fix for bug #17823, I discovered that EvalPlanQualStart failed to copy es_rteperminfos from the parent EState, resulting in failure if anything in EPQ execution wanted to consult that information. This led me to conclude that commit a61b1f748 had been too haphazard about where to fill es_rteperminfos, and that we need to be sure that that happens exactly where es_range_table gets filled. So I changed the signature of ExecInitRangeTable to help ensure that this new requirement doesn't get missed. (Indeed, pgoutput.c was also failing to fill it. Maybe we don't ever need it there, but I wouldn't bet on that.) No test case yet; one will arrive with the fix for #17823. But that needs to be back-patched, while this fix is HEAD-only. Discussion: https://postgr.es/m/17823-b64909cf7d63de84@postgresql.org
* Remove local optimizations of empty Bitmapsets into null pointers.Tom Lane2023-03-02
| | | | | | | | These are all dead code now that it's done centrally. Patch by me; thanks to Nathan Bossart and Richard Guo for review. Discussion: https://postgr.es/m/1159933.1677621588@sss.pgh.pa.us
* Mop up some undue familiarity with the innards of Bitmapsets.Tom Lane2023-03-02
| | | | | | | | | | | | | | | | | | | | | nodeAppend.c used non-nullness of appendstate->as_valid_subplans as a state flag to indicate whether it'd done ExecFindMatchingSubPlans (or some sufficient approximation to that). This was pretty questionable even in the beginning, since it wouldn't really work right if there are no valid subplans. It got more questionable after commit 27e1f1456 added logic that could reduce as_valid_subplans to an empty set: at that point we were depending on unspecified behavior of bms_del_members, namely that it'd not return an empty set as NULL. It's about to start doing that, which breaks this logic entirely. Hence, add a separate boolean flag to signal whether as_valid_subplans has been computed. Also fix a previously-cosmetic bug in nodeAgg.c, wherein it ignored the return value of bms_del_member instead of updating its pointer. Patch by me; thanks to Nathan Bossart and Richard Guo for review. Discussion: https://postgr.es/m/1159933.1677621588@sss.pgh.pa.us
* Remove bms_first_member().Tom Lane2023-03-02
| | | | | | | | | | | | | | This function has been semi-deprecated ever since we invented bms_next_member(). Its habit of scribbling on the input bitmapset isn't great, plus for sufficiently large bitmapsets it would take O(N^2) time to complete a loop. Now we have the additional problem that reducing the input to empty while leaving it still accessible would violate a planned invariant. So let's just get rid of it, after updating the few extant callers to use bms_next_member(). Patch by me; thanks to Nathan Bossart and Richard Guo for review. Discussion: https://postgr.es/m/1159933.1677621588@sss.pgh.pa.us
* Fix MULTIEXPR_SUBLINK with partitioned target tables, yet again.Tom Lane2023-02-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We already tried to fix this in commits 3f7323cbb et al (and follow-on fixes), but now it emerges that there are still unfixed cases; moreover, these cases affect all branches not only pre-v14. I thought we had eliminated all cases of making multiple clones of an UPDATE's target list when we nuked inheritance_planner. But it turns out we still do that in some partitioned-UPDATE cases, notably including INSERT ... ON CONFLICT UPDATE, because ExecInitPartitionInfo thinks it's okay to clone and modify the parent's targetlist. This fix is based on a suggestion from Andres Freund: let's stop abusing the ParamExecData.execPlan mechanism, which was only ever meant to handle initplans, and instead solve the execution timing problem by having the expression compiler move MULTIEXPR_SUBLINK steps to the front of their expression step lists. This is feasible because (a) all branches still in support compile the entire targetlist of an UPDATE into a single ExprState, and (b) we know that all MULTIEXPR_SUBLINKs do need to be evaluated --- none could be buried inside a CASE, for example. There is a minor semantics change concerning the order of execution of the MULTIEXPR's subquery versus other parts of the parent targetlist, but that seems like something we can get away with. By doing that, we no longer need to worry about whether different clones of a MULTIEXPR_SUBLINK share output Params; their usage of that data structure won't overlap. Per bug #17800 from Alexander Lakhin. Back-patch to all supported branches. In v13 and earlier, we can revert 3f7323cbb and follow-on fixes; however, I chose to keep the SubPlan.subLinkId field added in ccbb54c72. We don't need that anymore in the core code, but it's cheap enough to fill, and removing a plan node field in a minor release seems like it'd be asking for trouble. Andres Freund and Tom Lane Discussion: https://postgr.es/m/17800-ff90866b3906c964@postgresql.org
* Add missing support for the latest SPI status codes.Dean Rasheed2023-02-22
| | | | | | | | | | | | | | | | | | | SPI_result_code_string() was missing support for SPI_OK_TD_REGISTER, and in v15 and later, it was missing support for SPI_OK_MERGE, as was pltcl_process_SPI_result(). The last of those would trigger an error if a MERGE was executed from PL/Tcl. The others seem fairly innocuous, but worth fixing. Back-patch to all supported branches. Before v15, this is just adding SPI_OK_TD_REGISTER to SPI_result_code_string(), which is unlikely to be seen by anyone, but seems worth doing for completeness. Reviewed by Tom Lane. Discussion: https://postgr.es/m/CAEZATCUg8V%2BK%2BGcafOPqymxk84Y_prXgfe64PDoopjLFH6Z0Aw%40mail.gmail.com https://postgr.es/m/CAEZATCUMe%2B_KedPMM9AxKqm%3DSZogSxjUcrMe%2BsakusZh3BFcQw%40mail.gmail.com