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* Avoid allocating unnecessary zero-sized array.Jeff Davis2020-03-24
| | | | | If there are no aggregates, there is no need to allocate an array of zero AggStatePerGroupData elements.
* Improve the internal implementation of ereport().Tom Lane2020-03-24
| | | | | | | | | | | | | | | | | | | | | | Change all the auxiliary error-reporting routines to return void, now that we no longer need to pretend they are passing something useful to errfinish(). While this probably doesn't save anything significant at the machine-code level, it allows detection of some additional types of mistakes. Pass the error location details (__FILE__, __LINE__, PG_FUNCNAME_MACRO) to errfinish not errstart. This shaves a few cycles off the case where errstart decides we're not going to emit anything. Re-implement elog() as a trivial wrapper around ereport(), removing the separate support infrastructure it used to have. Aside from getting rid of some now-surplus code, this means that elog() now really does have exactly the same semantics as ereport(), in particular that it can skip evaluation work if the message is not to be emitted. Andres Freund and Tom Lane Discussion: https://postgr.es/m/CA+fd4k6N8EjNvZpM8nme+y+05mz-SM8Z_BgkixzkA34R+ej0Kw@mail.gmail.com
* Fixes for Disk-based Hash Aggregation.Jeff Davis2020-03-23
| | | | | | | | | Justin Pryzby raised a couple issues with commit 1f39bce0. Fixed. Also, tweak the way the size of a hash entry is estimated and the number of buckets is estimated when calling BuildTupleHashTableExt(). Discussion: https://www.postgresql.org/message-id/20200319064222.GR26184@telsasoft.com
* Add object names to partition integrity violations.Amit Kapila2020-03-23
| | | | | | | | | | | | All errors of SQLSTATE class 23 should include the name of an object associated with the error in separate fields of the error report message. We do this so that applications need not try to extract them from the possibly-localized human-readable text of the message. Reported-by: Chris Bandy Author: Chris Bandy Reviewed-by: Amit Kapila and Amit Langote Discussion: https://postgr.es/m/0aa113a3-3c7f-db48-bcd8-f9290b2269ae@gmail.com
* Disk-based Hash Aggregation.Jeff Davis2020-03-18
| | | | | | | | | | | | | | | | | | | | | | While performing hash aggregation, track memory usage when adding new groups to a hash table. If the memory usage exceeds work_mem, enter "spill mode". In spill mode, new groups are not created in the hash table(s), but existing groups continue to be advanced if input tuples match. Tuples that would cause a new group to be created are instead spilled to a logical tape to be processed later. The tuples are spilled in a partitioned fashion. When all tuples from the outer plan are processed (either by advancing the group or spilling the tuple), finalize and emit the groups from the hash table. Then, create new batches of work from the spilled partitions, and select one of the saved batches and process it (possibly spilling recursively). Author: Jeff Davis Reviewed-by: Tomas Vondra, Adam Lee, Justin Pryzby, Taylor Vesely, Melanie Plageman Discussion: https://postgr.es/m/507ac540ec7c20136364b5272acbcd4574aa76ef.camel@j-davis.com
* Remove bogus assertion about polymorphic SQL function result.Tom Lane2020-03-17
| | | | | | | | | | | | | | | | | | It is possible to reach check_sql_fn_retval() with an unresolved polymorphic rettype, resulting in an assertion failure as demonstrated by one of the added test cases. However, the code following that throws what seems an acceptable error message, so just remove the Assert and adjust commentary. While here, I thought it'd be a good idea to provide some parallel tests of SQL-function and PL/pgSQL-function polymorphism behavior. Some of these cases are perhaps duplicative of tests elsewhere, but we hadn't any organized coverage of the topic AFAICS. Although that assertion's been wrong all along, it won't have any effect in production builds, so I'm not bothering to back-patch. Discussion: https://postgr.es/m/21569.1584314271@sss.pgh.pa.us
* Simplify the effective_io_concurrency setting.Thomas Munro2020-03-16
| | | | | | | | | | | | | | | | | | | | | The effective_io_concurrency GUC and equivalent tablespace option were previously passed through a formula based on a theory about RAID spindles and probabilities, to arrive at the number of pages to prefetch in bitmap heap scans. Tomas Vondra, Andres Freund and others argued that it was anachronistic and hard to justify, and commit 558a9165e08 already started down the path of bypassing it in new code. We agreed to drop that logic and use the value directly. For the default setting of 1, there is no change in effect. Higher settings can be converted from the old meaning to the new with: select round(sum(OLD / n::float)) from generate_series(1, OLD) s(n); We might want to consider renaming the GUC before the next release given the change in meaning, but it's not clear that many users had set it very carefully anyway. That decision is deferred for now. Discussion: https://postgr.es/m/CA%2BhUKGJUw08dPs_3EUcdO6M90GnjofPYrWp4YSLaBkgYwS-AqA%40mail.gmail.com
* Remove utils/acl.h from catalog/objectaddress.hPeter Eisentraut2020-03-10
| | | | | | | | | | | | | | | | | | The need for this was removed by 8b9e9644dc6a9bd4b7a97950e6212f63880cf18b. A number of files now need to include utils/acl.h or parser/parse_node.h explicitly where they previously got it indirectly somehow. Since parser/parse_node.h already includes nodes/parsenodes.h, the latter is then removed where the former was added. Also, remove nodes/pg_list.h from objectaddress.h, since that's included via nodes/parsenodes.h. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com> Discussion: https://www.postgresql.org/message-id/flat/7601e258-26b2-8481-36d0-dc9dca6f28f1%402ndquadrant.com
* Extend ExecBuildAggTrans() to support a NULL pointer check.Jeff Davis2020-03-04
| | | | | | | | | | | | | | | | | Optionally push a step to check for a NULL pointer to the pergroup state. This will be important for disk-based hash aggregation in combination with grouping sets. When memory limits are reached, a given tuple may find its per-group state for some grouping sets but not others. For the former, it advances the per-group state as normal; for the latter, it skips evaluation and the calling code will have to spill the tuple and reprocess it in a later batch. Add the NULL check as a separate expression step because in some common cases it's not needed. Discussion: https://postgr.es/m/20200221202212.ssb2qpmdgrnx52sj%40alap3.anarazel.de
* Introduce macros for typalign and typstorage constants.Tom Lane2020-03-04
| | | | | | | | | | | | | | | | | | | | | Our usual practice for "poor man's enum" catalog columns is to define macros for the possible values and use those, not literal constants, in C code. But for some reason lost in the mists of time, this was never done for typalign/attalign or typstorage/attstorage. It's never too late to make it better though, so let's do that. The reason I got interested in this right now is the need to duplicate some uses of the TYPSTORAGE constants in an upcoming ALTER TYPE patch. But in general, this sort of change aids greppability and readability, so it's a good idea even without any specific motivation. I may have missed a few places that could be converted, and it's even more likely that pending patches will re-introduce some hard-coded references. But that's not fatal --- there's no expectation that we'd actually change any of these values. We can clean up stragglers over time. Discussion: https://postgr.es/m/16457.1583189537@sss.pgh.pa.us
* Represent command completion tags as structsAlvaro Herrera2020-03-02
| | | | | | | | | | | | | | | | | | | | | | The backend was using strings to represent command tags and doing string comparisons in multiple places, but that's slow and unhelpful. Create a new command list with a supporting structure to use instead; this is stored in a tag-list-file that can be tailored to specific purposes with a caller-definable C macro, similar to what we do for WAL resource managers. The first first such uses are a new CommandTag enum and a CommandTagBehavior struct. Replace numerous occurrences of char *completionTag with a QueryCompletion struct so that the code no longer stores information about completed queries in a cstring. Only at the last moment, in EndCommand(), does this get converted to a string. EventTriggerCacheItem no longer holds an array of palloc’d tag strings in sorted order, but rather just a Bitmapset over the CommandTags. Author: Mark Dilger, with unsolicited help from Álvaro Herrera Reviewed-by: John Naylor, Tom Lane Discussion: https://postgr.es/m/981A9DB4-3F0C-4DA5-88AD-CB9CFF4D6CAD@enterprisedb.com
* Correctly re-use hash tables in buildSubPlanHash().Tom Lane2020-02-29
| | | | | | | | | | | | | | | | | | | | | | Commit 356687bd8 omitted to remove leftover code for destroying a hashed subplan's hash tables, with the result that the tables were always rebuilt not reused; this leads to severe memory leakage if a hashed subplan is re-executed enough times. Moreover, the code for reusing the hashnulls table had a typo that would have made it do the wrong thing if it were reached. Looking at the code coverage report shows severe under-coverage of the potential callers of ResetTupleHashTable, so add some test cases that exercise them. Andreas Karlsson and Tom Lane, per reports from Ranier Vilela and Justin Pryzby. Backpatch to v11, as the faulty commit was. Discussion: https://postgr.es/m/edb62547-c453-c35b-3ed6-a069e4d6b937@proxel.se Discussion: https://postgr.es/m/CAEudQAo=DCebm1RXtig9OH+QivpS97sMkikt0A9qHmMUs+g6ZA@mail.gmail.com Discussion: https://postgr.es/m/20200210032547.GA1412@telsasoft.com
* Remove obsolete comment.Tom Lane2020-02-29
| | | | Noted while studying subplan hash issue.
* Move src/backend/utils/hash/hashfn.c to src/commonRobert Haas2020-02-27
| | | | | | | | | | | | | | This also involves renaming src/include/utils/hashutils.h, which becomes src/include/common/hashfn.h. Perhaps an argument can be made for keeping the hashutils.h name, but it seemed more consistent to make it match the name of the file, and also more descriptive of what is actually going on here. Patch by me, reviewed by Suraj Kharage and Mark Dilger. Off-list advice on how not to break the Windows build from Davinder Singh and Amit Kapila. Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
* expression eval: Reduce number of steps for agg transition invocations.Andres Freund2020-02-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do so by combining the various steps that are part of aggregate transition function invocation into one larger step. As some of the current steps are only necessary for some aggregates, have one variant of the aggregate transition step for each possible combination. To avoid further manual copies of code in the different transition step implementations, move most of the code into helper functions marked as "always inline". The benefit of this change is an increase in performance when aggregating lots of rows. This comes in part due to the reduced number of indirect jumps due to the reduced number of steps, and in part by reducing redundant setup code across steps. This mainly benefits interpreted execution, but the code generated by JIT is also improved a bit. As a nice side-effect it also ends up making the code a bit simpler. A small additional optimization is removing the need to set aggstate->curaggcontext before calling ExecAggInitGroup, choosing to instead passign curaggcontext as an argument. It was, in contrast to other aggregate related functions, only needed to fetch a memory context to copy the transition value into. Author: Andres Freund Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de https://postgr.es/m/5c371df7cee903e8cd4c685f90c6c72086d3a2dc.camel@j-davis.com
* Fixup for nodeAgg.c refactor.Jeff Davis2020-02-21
| | | | Commit 5b618e1f made an unintended behavior change.
* Minor refactor of nodeAgg.c.Jeff Davis2020-02-19
| | | | | | | | | | | | * Separate calculation of hash value from the lookup. * Split build_hash_table() into two functions. * Change lookup_hash_entry() to return AggStatePerGroup. That's all the caller needed, anyway. These changes are to support the upcoming Disk-based Hash Aggregation work. Discussion: https://postgr.es/m/31f5ab871a3ad5a1a91a7a797651f20e77ac7ce3.camel%40j-davis.com
* Remove duplicated words in commentsMichael Paquier2020-02-18
| | | | | | Author: Daniel Gustafsson Reviewed-by: Vik Fearing Discussion: https://postgr.es/m/EBC3BFEB-664C-4063-81ED-29F1227DB012@yesql.se
* Optimize update of tables with generated columnsPeter Eisentraut2020-02-17
| | | | | | | | | | | When updating a table row with generated columns, only recompute those generated columns whose base columns have changed in this update and keep the rest unchanged. This can result in a significant performance benefit. The required information was already kept in RangeTblEntry.extraUpdatedCols; we just have to make use of it. Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/b05e781a-fa16-6b52-6738-761181204567@2ndquadrant.com
* Change signature of TupleHashTableHash().Jeff Davis2020-02-10
| | | | | | | | Commit 4eaea3db introduced TupleHashTableHash(), but the signature didn't match the other exposed functions. Separate it into internal and external versions. The external version hides the details behind an API more consistent with the other external functions, and the internal version is still suitable for simplehash.
* Fix bug in Tid scan.Fujii Masao2020-02-07
| | | | | | | | | | | | | | | | | | | | | | | Commit 147e3722f7 changed Tid scan so that it calls table_beginscan() and uses the scan option for seq scan. This change caused two issues. (1) The change caused Tid scan to take a predicate lock on the entire relation in serializable transaction even when relation-level lock is not necessary. This could lead to an unexpected serialization error. (2) The change caused Tid scan to increment the number of seq_scan in pg_stat_*_tables views even though it's not seq scan. This could confuse the users. This commit adds the scan option for Tid scan and makes Tid scan use it, to avoid those issues. Back-patch to v12, where the bug was introduced. Author: Tatsuhito Kasahara Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Fujii Masao Discussion: https://postgr.es/m/CAP0=ZVKy+gTbFmB6X_UW0pP3WaeJ-fkUWHoD-pExS=at3CY76g@mail.gmail.com
* Introduce TupleHashTableHash() and LookupTupleHashEntryHash().Jeff Davis2020-02-06
| | | | | | | | | | Expose two new entry points: one for only calculating the hash value of a tuple, and another for looking up a hash entry when the hash value is already known. This will be useful for disk-based Hash Aggregation to avoid recomputing the hash value for the same tuple after saving and restoring it from disk. Discussion: https://postgr.es/m/37091115219dd522fd9ed67333ee8ed1b7e09443.camel%40j-davis.com
* expression eval: Don't redundantly keep track of AggState.Andres Freund2020-02-06
| | | | | | | | | | It's already tracked via ExprState->parent, so we don't need to also include it in ExprEvalStep. When that code originally was written ExprState->parent didn't exist, but it since has been introduced in 6719b238e8f. Author: Andres Freund Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de
* expression eval, jit: Minor code cleanups.Andres Freund2020-02-06
| | | | | | | | | | This mostly consists of using C99 style for loops, moving variables into narrower scopes, and a smattering of other minor improvements. Done separately to make it easier to review patches with actual functional changes. Author: Andres Freund Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de
* Refactor hash_agg_entry_size().Jeff Davis2020-02-06
| | | | | | Consolidate the calculations for hash table size estimation. This will help with upcoming Hash Aggregation work that will add additional call sites.
* Add missing break out seqscan loop in logical replicationAlvaro Herrera2020-02-03
| | | | | | | | | | | | | When replica identity is FULL (an admittedly unusual case), the loop that searches for tuples in execReplication.c didn't stop scanning the table when once a matching tuple was found. Add the missing 'break'. Note slight behavior change: we now return the first matching tuple rather than the last one. They are supposed to be indistinguishable anyway, so this shouldn't matter. Author: Konstantin Knizhnik Discussion: https://postgr.es/m/379743f6-ae91-b866-f7a2-5624e6d2b0a4@postgrespro.ru
* Clean up newlines following left parenthesesAlvaro Herrera2020-01-30
| | | | | | | | | | | | We used to strategically place newlines after some function call left parentheses to make pgindent move the argument list a few chars to the left, so that the whole line would fit under 80 chars. However, pgindent no longer does that, so the newlines just made the code vertically longer for no reason. Remove those newlines, and reflow some of those lines for some extra naturality. Reviewed-by: Michael Paquier, Tom Lane Discussion: https://postgr.es/m/20200129200401.GA6303@alvherre.pgsql
* 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