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* Fix dangling pointer in EvalPlanQual machinery.Tom Lane2020-01-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | EvalPlanQualStart() supposed that it could re-use the relsubs_rowmark and relsubs_done arrays from a prior instantiation. But since they are allocated in the es_query_cxt of the recheckestate, that's just wrong; EvalPlanQualEnd() will blow away that storage. Therefore we were using storage that could have been reallocated to something else, causing all sorts of havoc. I think this was modeled on the old code's handling of es_epqTupleSlot, but since the code was anyway clearing the arrays at re-use, there's clearly no expectation of importing any outside state. So it's just a dubious savings of a couple of pallocs, which is negligible compared to setting up a new planstate tree. Therefore, just allocate the arrays always. (I moved the allocations slightly for readability.) In principle this bug could cause a problem whenever EPQ rechecks are needed in more than one target table of a ModifyTable plan node. In practice it seems not quite so easy to trigger as that; I couldn't readily duplicate a crash with a partitioned target table, for instance. That's probably down to incidental choices about when to free or reallocate stuff. The added isolation test case does seem to reliably show an assertion failure, though. Per report from Oleksii Kliukin. Back-patch to v12 where the bug was introduced (evidently by commit 3fb307bc4). Discussion: https://postgr.es/m/EEF05F66-2871-4786-992B-5F45C92FEE2E@hintbits.com
* Added relation name in error messages for constraint checks.Amit Kapila2020-01-28
| | | | | | | | | | This gives more information to the user about the error and it makes such messages consistent with the other similar messages in the code. Reported-by: Simon Riggs Author: Mahendra Singh and Simon Riggs Reviewed-by: Beena Emerson and Amit Kapila Discussion: https://postgr.es/m/CANP8+j+7YUvQvGxTrCiw77R23enMJ7DFmyA3buR+fa2pKs4XhA@mail.gmail.com
* Avoid unnecessary shm writes in Parallel Hash Join.Thomas Munro2020-01-27
| | | | | | | | | | | | | | Currently, Parallel Hash Join cannot be used for full/right joins, so there is no point in setting the match flag. It turns out that the cache coherence traffic generated by those writes slows down large systems running many-core joins, so let's stop doing that. In future, if we need to use match bits in parallel joins, we might want to consider setting them only if not already set. Back-patch to 11, where Parallel Hash Join arrived. Reported-by: Deng, Gang Discussion: https://postgr.es/m/0F44E799048C4849BAE4B91012DB910462E9897A%40SHSMSX103.ccr.corp.intel.com
* Fix edge case leading to agg transitions skipping ExecAggTransReparent() calls.Andres Freund2020-01-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The code checking whether an aggregate transition value needs to be reparented into the current context has always only compared the transition return value with the previous transition value by datum, i.e. without regard for NULLness. This normally works, because when the transition function returns NULL (via fcinfo->isnull), it'll return a value that won't be the same as its input value. But there's no hard requirement that that's the case. And it turns out, it's possible to hit this case (see discussion or reproducers), leading to a non-null transition value not being reparented, followed by a crash caused by that. Instead of adding another comparison of NULLness, instead have ExecAggTransReparent() ensure that pergroup->transValue ends up as 0 when the new transition value is NULL. That avoids having to add an additional branch to the much more common cases of the transition function returning the old transition value (which is a pointer in this case), and when the new value is different, but not NULL. In branches since 69c3936a149, also deduplicate the reparenting code between the expression evaluation based transitions, and the path for ordered aggregates. Reported-By: Teodor Sigaev, Nikita Glukhov Author: Andres Freund Discussion: https://postgr.es/m/bd34e930-cfec-ea9b-3827-a8bc50891393@sigaev.ru Backpatch: 9.4-, this issue has existed since at least 7.4
* Repair more failures with SubPlans in multi-row VALUES lists.Tom Lane2020-01-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 9b63c13f0 turns out to have been fundamentally misguided: the parent node's subPlan list is by no means the only way in which a child SubPlan node can be hooked into the outer execution state. As shown in bug #16213 from Matt Jibson, we can also get short-lived tuple table slots added to the outer es_tupleTable list. At this point I have little faith that there aren't other possible connections as well; the long time it took to notice this problem shows that this isn't a heavily-exercised situation. Therefore, revert that fix, returning to the coding that passed a NULL parent plan pointer down to the transiently-built subexpressions. That gives us a pretty good guarantee that they won't hook into the outer executor state in any way. But then we need some other solution to make SubPlans work. Adopt the solution speculated about in the previous commit's log message: do expression initialization at plan startup for just those VALUES rows containing SubPlans, abandoning the goal of reclaiming memory intra-query for those rows. In practice it seems unlikely that queries containing a vast number of VALUES rows would be using SubPlans in them, so this should not give up much. (BTW, this test case also refutes my claim in connection with the prior commit that the issue only arises with use of LATERAL. That was just wrong: some variants of SubLink always produce SubPlans.) As with previous patch, back-patch to all supported branches. Discussion: https://postgr.es/m/16213-871ac3bc208ecf23@postgresql.org
* Fix problems with "read only query" checks, and refactor the code.Robert Haas2020-01-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, check_xact_readonly() was responsible for determining which types of queries could not be run in a read-only transaction, standard_ProcessUtility() was responsibility for prohibiting things which were allowed in read only transactions but not in recovery, and utility commands were basically prohibited in bulk in parallel mode by calls to CommandIsReadOnly() in functions.c and spi.c. This situation was confusing and error-prone. Accordingly, move all the checks to a new function ClassifyUtilityCommandAsReadOnly(), which determines the degree to which a given statement is read only. In the old code, check_xact_readonly() inadvertently failed to handle several statement types that actually should have been prohibited, specifically T_CreatePolicyStmt, T_AlterPolicyStmt, T_CreateAmStmt, T_CreateStatsStmt, T_AlterStatsStmt, and T_AlterCollationStmt. As a result, thes statements were erroneously allowed in read only transactions, parallel queries, and standby operation. Generally, they would fail anyway due to some lower-level error check, but we shouldn't rely on that. In the new code structure, future omissions of this type should cause ClassifyUtilityCommandAsReadOnly() to complain about an unrecognized node type. As a fringe benefit, this means we can allow certain types of utility commands in parallel mode, where it's safe to do so. This allows ALTER SYSTEM, CALL, DO, CHECKPOINT, COPY FROM, EXPLAIN, and SHOW. It might be possible to allow additional commands with more work and thought. Along the way, document the thinking process behind the current set of checks, as per discussion especially with Peter Eisentraut. There is some interest in revising some of these rules, but that seems like a job for another patch. Patch by me, reviewed by Tom Lane, Stephen Frost, and Peter Eisentraut. Discussion: http://postgr.es/m/CA+TgmoZ_rLqJt5sYkvh+JpQnfX0Y+B2R+qfi820xNih6x-FQOQ@mail.gmail.com
* Make rewriter prevent auto-updates on views with conditional INSTEAD rules.Dean Rasheed2020-01-14
| | | | | | | | | | | | | | | | | | | | A view with conditional INSTEAD rules and no unconditional INSTEAD rules or INSTEAD OF triggers is not auto-updatable. Previously we relied on a check in the executor to catch this, but that's problematic since the planner may fail to properly handle such a query and thus return a particularly unhelpful error to the user, before reaching the executor check. Instead, trap this in the rewriter and report the correct error there. Doing so also allows us to include more useful error detail than the executor check can provide. This doesn't change the existing behaviour of updatable views; it merely ensures that useful error messages are reported when a view isn't updatable. Per report from Pengzhou Tang, though not adopting that suggested fix. Back-patch to all supported branches. Discussion: https://postgr.es/m/CAG4reAQn+4xB6xHJqWdtE0ve_WqJkdyCV4P=trYr4Kn8_3_PEA@mail.gmail.com
* Improve the handling of result type coercions in SQL functions.Tom Lane2020-01-08
| | | | | | | | | | | | | | | | | | | | | | Use the parser's standard type coercion machinery to convert the output column(s) of a SQL function's final SELECT or RETURNING to the type(s) they should have according to the function's declared result type. We'll allow any case where an assignment-level coercion is available. Previously, we failed unless the required coercion was a binary-compatible one (and the documentation ignored this, falsely claiming that the types must match exactly). Notably, the coercion now accounts for typmods, so that cases where a SQL function is declared to return a composite type whose columns are typmod-constrained now behave as one would expect. Arguably this aspect is a bug fix, but the overall behavioral change here seems too large to consider back-patching. A nice side-effect is that functions can now be inlined in a few cases where we previously failed to do so because of type mismatches. Discussion: https://postgr.es/m/18929.1574895430@sss.pgh.pa.us
* Update copyrights for 2020Bruce Momjian2020-01-01
| | | | Backpatch-through: update all files in master, backpatch legal files through 9.4
* Revert "Rename files and headers related to index AM"Michael Paquier2019-12-27
| | | | | | | | This follows multiple complains from Peter Geoghegan, Andres Freund and Alvaro Herrera that this issue ought to be dug more before actually happening, if it happens. Discussion: https://postgr.es/m/20191226144606.GA5659@alvherre.pgsql
* Load relcache entries' partitioning data on-demand, not immediately.Tom Lane2019-12-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Formerly the rd_partkey and rd_partdesc data structures were always populated immediately when a relcache entry was built or rebuilt. This patch changes things so that they are populated only when they are first requested. (Hence, callers *must* now always use RelationGetPartitionKey or RelationGetPartitionDesc; just fetching the pointer directly is no longer acceptable.) This seems to have some performance benefits, but the main reason to do it is that it eliminates a recursive-reload failure that occurs if the partkey or partdesc expressions contain any references to the relation's rowtype (as discovered by Amit Langote). In retrospect, since loading these data structures might result in execution of nearly-arbitrary code via eval_const_expressions, it was a dumb idea to require that to happen during relcache entry rebuild. Also, fix things so that old copies of a relcache partition descriptor will be dropped when the cache entry's refcount goes to zero. In the previous coding it was possible for such copies to survive for the lifetime of the session, as I'd complained of in a previous discussion. (This management technique still isn't perfect, but it's better than before.) Improve the commentary explaining how that works and why it's safe to hand out direct pointers to these relcache substructures. In passing, improve RelationBuildPartitionDesc by using the same memory-context-parent-swap approach used by RelationBuildPartitionKey, thereby making it less dependent on strong assumptions about what partition_bounds_copy does. Avoid doing get_rel_relkind in the critical section, too. Patch by Amit Langote and Tom Lane; Robert Haas deserves some credit for prior work in the area, too. Although this is a pre-existing problem, no back-patch: the patch seems too invasive to be safe to back-patch, and the bug it fixes is a corner case that seems relatively unlikely to cause problems in the field. Discussion: https://postgr.es/m/CA+HiwqFUzjfj9HEsJtYWcr1SgQ_=iCAvQ=O2Sx6aQxoDu4OiHw@mail.gmail.com Discussion: https://postgr.es/m/CA+TgmoY3bRmGB6-DUnoVy5fJoreiBJ43rwMrQRCdPXuKt4Ykaw@mail.gmail.com
* Rename files and headers related to index AMMichael Paquier2019-12-25
| | | | | | | | | | | | | | | | | | | | | The following renaming is done so as source files related to index access methods are more consistent with table access methods (the original names used for index AMs ware too generic, and could be confused as including features related to table AMs): - amapi.h -> indexam.h. - amapi.c -> indexamapi.c. Here we have an equivalent with backend/access/table/tableamapi.c. - amvalidate.c -> indexamvalidate.c. - amvalidate.h -> indexamvalidate.h. - genam.c -> indexgenam.c. - genam.h -> indexgenam.h. This has been discussed during the development of v12 when table AM was worked on, but the renaming never happened. Author: Michael Paquier Reviewed-by: Fabien Coelho, Julien Rouhaud Discussion: https://postgr.es/m/20191223053434.GF34339@paquier.xyz
* Avoid splitting C string literals with \-newlineAlvaro Herrera2019-12-24
| | | | | | | | | | | Using \ is unnecessary and ugly, so remove that. While at it, stitch the literals back into a single line: we've long discouraged splitting error message literals even when they go past the 80 chars line limit, to improve greppability. Leave contrib/tablefunc alone. Discussion: https://postgr.es/m/20191223195156.GA12271@alvherre.pgsql
* Rotate instead of shifting hash join batch number.Thomas Munro2019-12-24
| | | | | | | | | | | | | | | | | | | Our algorithm for choosing batch numbers turned out not to work effectively for multi-billion key inner relations. We would use more hash bits than we have, and effectively concentrate all tuples into a smaller number of batches than we intended. While ideally we should switch to wider hashes, for now, change the algorithm to one that effectively gives up bits from the bucket number when we don't have enough bits. That means we'll finish up with longer bucket chains than would be ideal, but that's better than having batches that don't fit in work_mem and can't be divided. Batch-patch to all supported releases. Author: Thomas Munro Reviewed-by: Tom Lane, thanks also to Tomas Vondra, Alvaro Herrera, Andres Freund for testing and discussion Reported-by: James Coleman Discussion: https://postgr.es/m/16104-dc11ed911f1ab9df%40postgresql.org
* Refactor attribute mappings used in logical tuple conversionMichael Paquier2019-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | Tuple conversion support in tupconvert.c is able to convert rowtypes between two relations, inner and outer, which are logically equivalent but have a different ordering or even dropped columns (used mainly for inheritance tree and partitions). This makes use of attribute mappings, which are simple arrays made of AttrNumber elements with a length matching the number of attributes of the outer relation. The length of the attribute mapping has been treated as completely independent of the mapping itself until now, making it easy to pass down an incorrect mapping length. This commit refactors the code related to attribute mappings and moves it into an independent facility called attmap.c, extracted from tupconvert.c. This merges the attribute mapping with its length, avoiding to try to guess what is the length of a mapping to use as this is computed once, when the map is built. This will avoid mistakes like what has been fixed in dc816e58, which has used an incorrect mapping length by matching it with the number of attributes of an inner relation (a child partition) instead of an outer relation (a partitioned table). Author: Michael Paquier Reviewed-by: Amit Langote Discussion: https://postgr.es/m/20191121042556.GD153437@paquier.xyz
* Remove redundant not-null testBruce Momjian2019-12-17
| | | | | | | | | | Reported-by: Ranier Vilela Discussion: https://postgr.es/m/MN2PR18MB2927E73FADCA8967B2302469E3490@MN2PR18MB2927.namprd18.prod.outlook.com Author: Ranier Vilela Backpatch-through: master
* Allow executor startup pruning to prune all child nodes.Tom Lane2019-12-11
| | | | | | | | | | | | | Previously, if the startup pruning logic proved that all child nodes of an Append or MergeAppend could be pruned, we still kept one, just to keep EXPLAIN from failing. The previous commit removed the ruleutils.c limitation that required this kluge, so drop it. That results in less-confusing EXPLAIN output, as per a complaint from Yuzuko Hosoya. David Rowley Discussion: https://postgr.es/m/001001d4f44b$2a2cca50$7e865ef0$@lab.ntt.co.jp
* Further adjust EXPLAIN's choices of table alias names.Tom Lane2019-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch causes EXPLAIN to always assign a separate table alias to the parent RTE of an append relation (inheritance set); before, such RTEs were ignored if not actually scanned by the plan. Since the child RTEs now always have that same alias to start with (cf. commit 55a1954da), the net effect is that the parent RTE usually gets the alias used or implied by the query text, and the children all get that alias with "_N" appended. (The exception to "usually" is if there are duplicate aliases in different subtrees of the original query; then some of those original RTEs will also have "_N" appended.) This results in more uniform output for partitioned-table plans than we had before: the partitioned table itself gets the original alias, and all child tables have aliases with "_N", rather than the previous behavior where one of the children would get an alias without "_N". The reason for giving the parent RTE an alias, even if it isn't scanned by the plan, is that we now use the parent's alias to qualify Vars that refer to an appendrel output column and appear above the Append or MergeAppend that computes the appendrel. But below the append, Vars refer to some one of the child relations, and are displayed that way. This seems clearer than the old behavior where a Var that could carry values from any child relation was displayed as if it referred to only one of them. While at it, change ruleutils.c so that the code paths used by EXPLAIN deal in Plan trees not PlanState trees. This effectively reverts a decision made in commit 1cc29fe7c, which seemed like a good idea at the time to make ruleutils.c consistent with explain.c. However, it's problematic because we'd really like to allow executor startup pruning to remove all the children of an append node when possible, leaving no child PlanState to resolve Vars against. (That's not done here, but will be in the next patch.) This requires different handling of subplans and initplans than before, but is otherwise a pretty straightforward change. Discussion: https://postgr.es/m/001001d4f44b$2a2cca50$7e865ef0$@lab.ntt.co.jp
* Fix comments in execGrouping.cJeff Davis2019-12-06
| | | | | | | | | Commit 5dfc1981 missed updating some comments. Also, fix a comment typo found in passing. Author: Jeff Davis Discussion: https://postgr.es/m/9723131d247b919f94699152647fa87ee0bc02c2.camel%40j-davis.com
* Fix whitespace.Etsuro Fujita2019-12-04
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* Remove useless "return;" linesAlvaro Herrera2019-11-28
| | | | Discussion: https://postgr.es/m/20191128144653.GA27883@alvherre.pgsql
* Don't shut down Gather[Merge] early under Limit.Amit Kapila2019-11-26
| | | | | | | | | | | | | | | | | | | Revert part of commit 19df1702f5. Early shutdown was added by that commit so that we could collect statistics from workers, but unfortunately, it interacted badly with rescans. The problem is that we ended up destroying the parallel context which is required for rescans. This leads to rescans of a Limit node over a Gather node to produce unpredictable results as it tries to access destroyed parallel context. By reverting the early shutdown code, we might lose statistics in some cases of Limit over Gather [Merge], but that will require further study to fix. Reported-by: Jerry Sievers Diagnosed-by: Thomas Munro Author: Amit Kapila, testcase by Vignesh C Backpatch-through: 9.6 Discussion: https://postgr.es/m/87ims2amh6.fsf@jsievers.enova.com
* Always call ExecShutdownNode() if appropriate.Thomas Munro2019-11-16
| | | | | | | | | | | | | | Call ExecShutdownNode() after ExecutePlan()'s loop, rather than at each break. We had forgotten to do that in one case. The omission caused intermittent "temporary file leak" warnings from multi-batch parallel hash joins with a LIMIT clause. Back-patch to 11. Though the problem exists in theory in earlier parallel query releases, nothing really depended on it. Author: Kyotaro Horiguchi Reviewed-by: Thomas Munro, Amit Kapila Discussion: https://postgr.es/m/20191111.212418.2222262873417235945.horikyota.ntt%40gmail.com
* Make the order of the header file includes consistent in backend modules.Amit Kapila2019-11-12
| | | | | | | | | | | Similar to commits 7e735035f2 and dddf4cdc33, this commit makes the order of header file inclusion consistent for backend modules. In the passing, removed a couple of duplicate inclusions. Author: Vignesh C Reviewed-by: Kuntal Ghosh and Amit Kapila Discussion: https://postgr.es/m/CALDaNm2Sznv8RR6Ex-iJO6xAdsxgWhCoETkaYX=+9DW3q0QCfA@mail.gmail.com
* Add reusable routine for making arrays unique.Thomas Munro2019-11-07
| | | | | | | | | | Introduce qunique() and qunique_arg(), which can be used after qsort() and qsort_arg() respectively to remove duplicate values. Use it where appropriate. Author: Thomas Munro Reviewed-by: Tom Lane (in an earlier version) Discussion: https://postgr.es/m/CAEepm%3D2vmFTNpAmwbGGD2WaryM6T3hSDVKQPfUwjdD_5XY6vAA%40mail.gmail.com
* Minor code review for tuple slot rewrite.Tom Lane2019-11-06
| | | | | | | | | | | | | | | | | Avoid creating transiently-inconsistent slot states where possible, by not setting TTS_FLAG_SHOULDFREE until after the slot actually has a free'able tuple pointer, and by making sure that we reset tts_nvalid and related derived state before we replace the tuple contents. This would only matter if something were to examine the slot after we'd suffered some kind of error (e.g. out of memory) while manipulating the slot. We typically don't do that, so these changes might just be cosmetic --- but even if so, it seems like good future-proofing. Also remove some redundant Asserts, and add a couple for consistency. Back-patch to v12 where all this code was rewritten. Discussion: https://postgr.es/m/16095-c3ff2e5283b8dba5@postgresql.org
* Split all OBJS style lines in makefiles into one-line-per-entry style.Andres Freund2019-11-05
| | | | | | | | | | | | | | | When maintaining or merging patches, one of the most common sources for conflicts are the list of objects in makefiles. Especially when the split across lines has been changed on both sides, which is somewhat common due to attempting to stay below 80 columns, those conflicts are unnecessarily laborious to resolve. By splitting, and alphabetically sorting, OBJS style lines into one object per line, conflicts should be less frequent, and easier to resolve when they still occur. Author: Andres Freund Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
* Rename some toasting functions based on whether they are heap-specific.Robert Haas2019-10-04
| | | | | | | | | | | | | | | | | | | | | | The old names for the attribute-detoasting functions names included the word "heap," which seems outdated now that the heap is only one of potentially many table access methods. On the other hand, toast_insert_or_update and toast_delete are heap-specific, so rename them by adding "heap_" as a prefix. Not all of the work of making the TOAST system fully accessible to AMs other than the heap is done yet, but there seems to be little harm in getting this renaming out of the way now. Commit 8b94dab06617ef80a0901ab103ebd8754427ef5a already divided up the functions among various files partially according to whether it was intended that they should be heap-specific or AM-agnostic, so this is just clarifying the division contemplated by that commit. Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro, Andres Freund, and Álvaro Herrera. Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
* Don't generate EEOP_*_FETCHSOME operations for slots know to be virtual.Andres Freund2019-09-30
| | | | | | | | | | | | That avoids unnecessary work during both interpreted execution, and JIT compiled expression evaluation. Both benefit from fewer expression steps needing be processed, and for interpreted execution there now is a fastpath dedicated to just fetching a value from a virtual slot. That's e.g. beneficial for hashjoins over nodes that perform projections, as the hashed columns are currently fetched individually. Author: Soumyadeep Chakraborty, Andres Freund Discussion: https://postgr.es/m/CAE-ML+9OKSN71+mHtfMD-L24oDp8dGTfaVjDU6U+j+FNAW5kRQ@mail.gmail.com
* Reduce code duplication for ExecJust*Var operations.Andres Freund2019-09-30
| | | | | | | | | | | This is mainly in preparation for adding further fastpath evaluation routines. Also reorder ExecJust*Var functions to be consistent with the order in which they're used. Author: Andres Freund Discussion: https://postgr.es/m/CAE-ML+9OKSN71+mHtfMD-L24oDp8dGTfaVjDU6U+j+FNAW5kRQ@mail.gmail.com
* jit: Re-allow JIT compilation of execGrouping.c hashtable comparisons.Andres Freund2019-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In the course of 5567d12ce03, 356687bd8 and 317ffdfeaac, I changed BuildTupleHashTable[Ext]'s call to ExecBuildGroupingEqual to not pass in the parent node, but NULL. Which in turn prevents the tuple equality comparator from being JIT compiled. While that fixes bug #15486, it is not actually necessary after all of the above commits, as we don't re-build the comparator when using the new BuildTupleHashTableExt() interface (as the content of the hashtable are reset, but the TupleHashTable itself is not). Therefore re-allow jit compilation for callers that use BuildTupleHashTableExt with a separate context for "metadata" and content. As in the previous commit, there's ongoing work to make this easier to test to prevent such regressions in the future, but that infrastructure is not going to be backpatchable. The performance impact of not JIT compiling hashtable equality comparators can be substantial e.g. for aggregation queries that aggregate a lot of input rows to few output rows (when there are a lot of output groups, there will be fewer comparisons). Author: Andres Freund Discussion: https://postgr.es/m/20190927072053.njf6prdl3vb7y7qb@alap3.anarazel.de Backpatch: 11, just as 5567d12ce03
* Fix determination when slot types for upper executor nodes are fixed.Andres Freund2019-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | For many queries the fact that the tuple descriptor from the lower node was not taken into account when determining whether the type of a slot is fixed, lead to tuple deforming for such upper nodes not to be JIT accelerated. I broke this in 675af5c01e297. There is ongoing work to enable writing regression tests for related behavior (including a patch that would have detected this regression), by optionally showing such details in EXPLAIN. But as it seems unlikely that that will be suitable for stable branches, just merge the fix for now. While it's fairly close to the 12 release window, the fact that 11 continues to perform JITed tuple deforming in these cases, that there's still cases where we do so in 12, and the fact that the performance regression can be sizable, weigh in favor of fixing it now. Author: Andres Freund Discussion: https://postgr.es/m/20190927072053.njf6prdl3vb7y7qb@alap3.anarazel.de Backpatch: 12-, where 675af5c01e297 was merged.
* Fix ExprState's tag to be of type NodeTag rather than Node.Andres Freund2019-09-23
| | | | | | | This appears to have been an oversight in b8d7f053c5c2. As it's effectively harmless, though confusing, only fix in master. Author: Andres Freund
* Fix typo in tts_virtual_copyslot.Tom Lane2019-09-22
| | | | | | | | | | | The code used the destination slot's natts where it intended to use the source slot's natts. Adding an Assert shows that there is no case in "make check-world" where these counts are different, so maybe this is a harmless bug, but it's still a bug. Takayuki Tsunakawa Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1FD34C0E@G01JPEXMBYT05
* Fix bogus sizeof calculations.Tom Lane2019-09-15
| | | | | Noted by Coverity. Typo in 27cc7cd2b, so back-patch to v12 as that was.
* Reorder EPQ work, to fix rowmark related bugs and improve efficiency.Andres Freund2019-09-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In ad0bda5d24ea I changed the EvalPlanQual machinery to store substitution tuples in slot, instead of using plain HeapTuples. The main motivation for that was that using HeapTuples will be inefficient for future tableams. But it turns out that that conversion was buggy for non-locking rowmarks - the wrong tuple descriptor was used to create the slot. As a secondary issue 5db6df0c0 changed ExecLockRows() to begin EPQ earlier, to allow to fetch the locked rows directly into the EPQ slots, instead of having to copy tuples around. Unfortunately, as Tom complained, that forces some expensive initialization to happen earlier. As a third issue, the test coverage for EPQ was clearly insufficient. Fixing the first issue is unfortunately not trivial: Non-locked row marks were fetched at the start of EPQ, and we don't have the type information for the rowmarks available at that point. While we could change that, it's not easy. It might be worthwhile to change that at some point, but to fix this bug, it seems better to delay fetching non-locking rowmarks when they're actually needed, rather than eagerly. They're referenced at most once, and in cases where EPQ fails, might never be referenced. Fetching them when needed also increases locality a bit. To be able to fetch rowmarks during execution, rather than initialization, we need to be able to access the active EPQState, as that contains necessary data. To do so move EPQ related data from EState to EPQState, and, only for EStates creates as part of EPQ, reference the associated EPQState from EState. To fix the second issue, change EPQ initialization to allow use of EvalPlanQualSlot() to be used before EvalPlanQualBegin() (but obviously still requiring EvalPlanQualInit() to have been done). As these changes made struct EState harder to understand, e.g. by adding multiple EStates, significantly reorder the members, and add a lot more comments. Also add a few more EPQ tests, including one that fails for the first issue above. More is needed. Reported-By: yi huang Author: Andres Freund Reviewed-By: Tom Lane Discussion: https://postgr.es/m/CAHU7rYZo_C4ULsAx_LAj8az9zqgrD8WDd4hTegDTMM1LMqrBsg@mail.gmail.com https://postgr.es/m/24530.1562686693@sss.pgh.pa.us Backpatch: 12-, where the EPQ changes were introduced
* Split tuptoaster.c into three separate files.Robert Haas2019-09-05
| | | | | | | | | | | | | | | | | | | | | | | | detoast.c/h contain functions required to detoast a datum, partially or completely, plus a few other utility functions for examining the size of toasted datums. toast_internals.c/h contain functions that are used internally to the TOAST subsystem but which (mostly) do not need to be accessed from outside. heaptoast.c/h contains code that is intrinsically specific to the heap AM, either because it operates on HeapTuples or is based on the layout of a heap page. detoast.c and toast_internals.c are placed in src/backend/access/common rather than src/backend/access/heap. At present, both files still have dependencies on the heap, but that will be improved in a future commit. Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro, Andres Freund, and Álvaro Herrera. Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
* Remove 'msg' parameter from convert_tuples_by_nameAlvaro Herrera2019-09-03
| | | | | | | | | | The message was included as a parameter when this function was added in dcb2bda9b704, but I don't think it has ever served any useful purpose. Let's stop spreading it pointlessly. Reviewed by Amit Langote and Peter Eisentraut. Discussion: https://postgr.es/m/20190806224728.GA17233@alvherre.pgsql
* Fix inconsistencies and typos in the tree, take 11Michael Paquier2019-08-19
| | | | | | | | This fixes various typos in docs and comments, and removes some orphaned definitions. Author: Alexander Lakhin Discussion: https://postgr.es/m/5da8e325-c665-da95-21e0-c8a99ea61fbf@gmail.com
* Don't include utils/array.h from acl.h.Andres Freund2019-08-16
| | | | | | | | | | | | | | | | | | For most uses of acl.h the details of how "Acl" internally looks like are irrelevant. It might make sense to move a lot of the implementation details into a separate header at a later point. The main motivation of this change is to avoid including fmgr.h (via array.h, which needs it for exposed structs) in a lot of files that otherwise don't need it. A subsequent commit will remove the fmgr.h include from a lot of files. Directly include utils/array.h and utils/expandeddatum.h from the files that need them, but previously included them indirectly, via acl.h. Author: Andres Freund Discussion: https://postgr.es/m/20190803193733.g3l3x3o42uv4qj7l@alap3.anarazel.de
* Fix inconsistencies and typos in the tree, take 10Michael Paquier2019-08-13
| | | | | | | | | This addresses some issues with unnecessary code comments, fixes various typos in docs and comments, and removes some orphaned structures and definitions. Author: Alexander Lakhin Discussion: https://postgr.es/m/9aabc775-5494-b372-8bcb-4dfc0bd37c68@gmail.com
* Remove EState.es_range_table_array.Tom Lane2019-08-12
| | | | | | | | | | Now that list_nth is O(1), there's no good reason to maintain a separate array of RTE pointers rather than indexing into estate->es_range_table. Deleting the array doesn't save all that much either; but just on cleanliness grounds, it's better not to have duplicate representations of the identical information. Discussion: https://postgr.es/m/14960.1565384592@sss.pgh.pa.us
* Rationalize use of list_concat + list_copy combinations.Tom Lane2019-08-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In the wake of commit 1cff1b95a, the result of list_concat no longer shares the ListCells of the second input. Therefore, we can replace "list_concat(x, list_copy(y))" with just "list_concat(x, y)". To improve call sites that were list_copy'ing the first argument, or both arguments, invent "list_concat_copy()" which produces a new list sharing no ListCells with either input. (This is a bit faster than "list_concat(list_copy(x), y)" because it makes the result list the right size to start with.) In call sites that were not list_copy'ing the second argument, the new semantics mean that we are usually leaking the second List's storage, since typically there is no remaining pointer to it. We considered inventing another list_copy variant that would list_free the second input, but concluded that for most call sites it isn't worth worrying about, given the relative compactness of the new List representation. (Note that in cases where such leakage would happen, the old code already leaked the second List's header; so we're only discussing the size of the leak not whether there is one. I did adjust two or three places that had been troubling to free that header so that they manually free the whole second List.) Patch by me; thanks to David Rowley for review. Discussion: https://postgr.es/m/11587.1550975080@sss.pgh.pa.us
* Fix choice of comparison operators for cross-type hashed subplans.Tom Lane2019-08-05
| | | | | | | | | | | | | | | | | | | | | | Commit bf6c614a2 rearranged the lookup of the comparison operators needed in a hashed subplan, and in so doing, broke the cross-type case: it caused the original LHS-vs-RHS operator to be used to compare hash table entries too (which of course are all of the RHS type). This leads to C functions being passed a Datum that is not of the type they expect, with the usual hazards of crashes and unauthorized server memory disclosure. For the set of hashable cross-type operators present in v11 core Postgres, this bug is nearly harmless on 64-bit machines, which may explain why it escaped earlier detection. But it is a live security hazard on 32-bit machines; and of course there may be extensions that add more hashable cross-type operators, which would increase the risk. Reported by Andreas Seltenreich. Back-patch to v11 where the problem came in. Security: CVE-2019-10209
* Fix inconsistencies and typos in the tree, take 9Michael Paquier2019-08-05
| | | | | | | | This addresses more issues with code comments, variable names and unreferenced variables. Author: Alexander Lakhin Discussion: https://postgr.es/m/7ab243e0-116d-3e44-d120-76b3df7abefd@gmail.com
* Fix representation of hash keys in Hash/HashJoin nodes.Andres Freund2019-08-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In 5f32b29c1819 I changed the creation of HashState.hashkeys to actually use HashState as the parent (instead of HashJoinState, which was incorrect, as they were executed below HashState), to fix the problem of hashkeys expressions otherwise relying on slot types appropriate for HashJoinState, rather than HashState as would be correct. That reliance was only introduced in 12, which is why it previously worked to use HashJoinState as the parent (although I'd be unsurprised if there were problematic cases). Unfortunately that's not a sufficient solution, because before this commit, the to-be-hashed expressions referenced inner/outer as appropriate for the HashJoin, not Hash. That didn't have obvious bad consequences, because the slots containing the tuples were put into ecxt_innertuple when hashing a tuple for HashState (even though Hash doesn't have an inner plan). There are less common cases where this can cause visible problems however (rather than just confusion when inspecting such executor trees). E.g. "ERROR: bogus varno: 65000", when explaining queries containing a HashJoin where the subsidiary Hash node's hash keys reference a subplan. While normally hashkeys aren't displayed by EXPLAIN, if one of those expressions references a subplan, that subplan may be printed as part of the Hash node - which then failed because an inner plan was referenced, and Hash doesn't have that. It seems quite possible that there's other broken cases, too. Fix the problem by properly splitting the expression for the HashJoin and Hash nodes at plan time, and have them reference the proper subsidiary node. While other workarounds are possible, fixing this correctly seems easy enough. It was a pretty ugly hack to have ExecInitHashJoin put the expression into the already initialized HashState, in the first place. I decided to not just split inner/outer hashkeys inside make_hashjoin(), but also to separate out hashoperators and hashcollations at plan time. Otherwise we would have ended up having two very similar loops, one at plan time and the other during executor startup. The work seems to more appropriately belong to plan time, anyway. Reported-By: Nikita Glukhov, Alexander Korotkov Author: Andres Freund Reviewed-By: Tom Lane, in an earlier version Discussion: https://postgr.es/m/CAPpHfdvGVegF_TKKRiBrSmatJL2dR9uwFCuR+teQ_8tEXU8mxg@mail.gmail.com Backpatch: 12-
* Remove superfluous newlines in function prototypes.Andres Freund2019-07-31
| | | | | | | | | | | | | | | These were introduced by pgindent due to fixe to broken indentation (c.f. 8255c7a5eeba8). Previously the mis-indentation of function prototypes was creatively used to reduce indentation in a few places. As that formatting only exists in master and REL_12_STABLE, it seems better to fix it in both, rather than having some odd indentation in v12 that somebody might copy for future patches or such. Author: Andres Freund Discussion: https://postgr.es/m/20190728013754.jwcbe5nfyt3533vx@alap3.anarazel.de Backpatch: 12-
* Fix slot type handling for Agg nodes performing internal sorts.Andres Freund2019-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 15d8f8312 we assert that - and since 7ef04e4d2cb2, 4da597edf1 rely on - the slot type for an expression's ecxt_{outer,inner,scan}tuple not changing, unless explicitly flagged as such. That allows to either skip deforming (for a virtual tuple slot) or optimize the code for JIT accelerated deforming appropriately (for other known slot types). This assumption was sometimes violated for grouping sets, when nodeAgg.c internally uses tuplesorts, and the child node doesn't return a TTSOpsMinimalTuple type slot. Detect that case, and flag that the outer slot might not be "fixed". It's probably worthwhile to optimize this further in the future, and more granularly determine whether the slot is fixed. As we already instantiate per-phase transition and equal expressions, we could cheaply set the slot type appropriately for each phase. But that's a separate change from this bugfix. This commit does include a very minor optimization by avoiding to create a slot for handling tuplesorts, if no such sorts are performed. Previously we created that slot unnecessarily in the common case of computing all grouping sets via hashing. The code looked too confusing without that, as the conditions for needing a sort slot and flagging that the slot type isn't fixed, are the same. Reported-By: Ashutosh Sharma Author: Andres Freund Discussion: https://postgr.es/m/CAE9k0PmNaMD2oHTEAhRyxnxpaDaYkuBYkLa1dpOpn=RS0iS2AQ@mail.gmail.com Backpatch: 12-, where the bug was introduced in 15d8f8312
* Fix system column accesses in ON CONFLICT ... RETURNING.Andres Freund2019-07-24
| | | | | | | | | | | | | | | | | After 277cb789836 ON CONFLICT ... SET ... RETURNING failed with ERROR: virtual tuple table slot does not have system attributes when taking the update path, as the slot used to insert into the table (and then process RETURNING) was defined to be a virtual slot in that commit. Virtual slots don't support system columns except for tableoid and ctid, as the other system columns are AM dependent. Fix that by using a slot of the table's type. Add tests for system column accesses in ON CONFLICT ... RETURNING. Reported-By: Roby, bisected to the relevant commit by Jeff Janes Author: Andres Freund Discussion: https://postgr.es/m/73436355-6432-49B1-92ED-1FE4F7E7E100@finefun.com.au Backpatch: 12-, where the bug was introduced in 277cb789836
* Use appendBinaryStringInfo in more places where the length is knownDavid Rowley2019-07-23
| | | | | | | | | | When we already know the length that we're going to append, then it makes sense to use appendBinaryStringInfo instead of appendStringInfoString so that the append can be performed with a simple memcpy() using a known length rather than having to first perform a strlen() call to obtain the length. Discussion: https://postgr.es/m/CAKJS1f8+FRAM1s5+mAa3isajeEoAaicJ=4e0WzrH3tAusbbiMQ@mail.gmail.com