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* Remove unused #includePeter Eisentraut2019-03-14
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* tableam: Add and use scan APIs.Andres Freund2019-03-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
* Store tuples for EvalPlanQual in slots, rather than as HeapTuples.Andres Freund2019-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | | For the upcoming pluggable table access methods it's quite inconvenient to store tuples as HeapTuples, as that'd require converting tuples from a their native format into HeapTuples. Instead use slots to manage epq tuples. To fit into that scheme, change the foreign data wrapper callback RefetchForeignRow, to store the tuple in a slot. Insist on using the caller provided slot, so it conveniently can be stored in the corresponding EPQ slot. As there is no in core user of RefetchForeignRow, that change was done blindly, but we plan to test that soon. To avoid duplicating that work for row locks, move row locks to just directly use the EPQ slots - it previously temporarily stored tuples in LockRowsState.lr_curtuples, but that doesn't seem beneficial, given we'd possibly end up with a significant number of additional slots. The behaviour of es_epqTupleSet[rti -1] is now checked by es_epqTupleSlot[rti -1] != NULL, as that is distinguishable from a slot containing an empty tuple. Author: Andres Freund, Haribabu Kommi, Ashutosh Bapat Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
* Use slots in trigger infrastructure, except for the actual invocation.Andres Freund2019-02-26
| | | | | | | | | | | | | | | | | | | | | In preparation for abstracting table storage, convert trigger.c to track tuples in slots. Which also happens to make code calling triggers simpler. As the calling interface for triggers themselves is not changed in this patch, HeapTuples still are extracted from the slot at that time. But that's handled solely inside trigger.c, not visible to callers. It's quite likely that we'll want to revise the external trigger interface, but that's a separate large project. As part of this work the slots used for old/new/return tuples are moved from EState into ResultRelInfo, as different updated tables might need different slots. The slots are now also now created on-demand, which is good both from an efficiency POV, but also makes the modifying code simpler. Author: Andres Freund, Amit Khandekar and Ashutosh Bapat Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
* Refactor planner's header files.Tom Lane2019-01-29
| | | | | | | | | | | | | | | | | | | | | | | | Create a new header optimizer/optimizer.h, which exposes just the planner functions that can be used "at arm's length", without need to access Paths or the other planner-internal data structures defined in nodes/relation.h. This is intended to provide the whole planner API seen by most of the rest of the system; although FDWs still need to use additional stuff, and more thought is also needed about just what selfuncs.c should rely on. The main point of doing this now is to limit the amount of new #include baggage that will be needed by "planner support functions", which I expect to introduce later, and which will be in relevant datatype modules rather than anywhere near the planner. This commit just moves relevant declarations into optimizer.h from other header files (a couple of which go away because everything got moved), and adjusts #include lists to match. There's further cleanup that could be done if we want to decide that some stuff being exposed by optimizer.h doesn't belong in the planner at all, but I'll leave that for another day. Discussion: https://postgr.es/m/11460.1548706639@sss.pgh.pa.us
* Remove superfluous tqual.h includes.Andres Freund2019-01-21
| | | | | | | | | | | | Most of these had been obsoleted by 568d4138c / the SnapshotNow removal. This is is preparation for moving most of tqual.[ch] into either snapmgr.h or heapam.h, which in turn is in preparation for pluggable table AMs. Author: Andres Freund Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
* Replace uses of heap_open et al with the corresponding table_* function.Andres Freund2019-01-21
| | | | | Author: Andres Freund Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
* Don't include heapam.h from others headers.Andres Freund2019-01-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | heapam.h previously was included in a number of widely used headers (e.g. execnodes.h, indirectly in executor.h, ...). That's problematic on its own, as heapam.h contains a lot of low-level details that don't need to be exposed that widely, but becomes more problematic with the upcoming introduction of pluggable table storage - it seems inappropriate for heapam.h to be included that widely afterwards. heapam.h was largely only included in other headers to get the HeapScanDesc typedef (which was defined in heapam.h, even though HeapScanDescData is defined in relscan.h). The better solution here seems to be to just use the underlying struct (forward declared where necessary). Similar for BulkInsertState. Another problem was that LockTupleMode was used in executor.h - parts of the file tried to cope without heapam.h, but due to the fact that it indirectly included it, several subsequent violations of that goal were not not noticed. We could just reuse the approach of declaring parameters as int, but it seems nicer to move LockTupleMode to lockoptions.h - that's not a perfect location, but also doesn't seem bad. As a number of files relied on implicitly included heapam.h, a significant number of files grew an explicit include. It's quite probably that a few external projects will need to do the same. Author: Andres Freund Reviewed-By: Alvaro Herrera Discussion: https://postgr.es/m/20190114000701.y4ttcb74jpskkcfb@alap3.anarazel.de
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Fix thinko in previous commitAlvaro Herrera2018-12-28
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* Rewrite ExecPartitionCheckEmitError for clarityAlvaro Herrera2018-12-28
| | | | | | The original was hard to follow and failed to comply with DRY principle. Discussion: https://postgr.es/m/20181206222221.g5witbsklvqthjll@alvherre.pgsql
* Remove WITH OIDS support, change oid catalog column visibility.Andres Freund2018-11-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
* Redesign initialization of partition routing structuresAlvaro Herrera2018-11-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This speeds up write operations (INSERT, UPDATE, DELETE, COPY, as well as the future MERGE) on partitioned tables. This changes the setup for tuple routing so that it does far less work during the initial setup and pushes more work out to when partitions receive tuples. PartitionDispatchData structs for sub-partitioned tables are only created when a tuple gets routed through it. The possibly large arrays in the PartitionTupleRouting struct have largely been removed. The partitions[] array remains but now never contains any NULL gaps. Previously the NULLs had to be skipped during ExecCleanupTupleRouting(), which could add a large overhead to the cleanup when the number of partitions was large. The partitions[] array is allocated small to start with and only enlarged when we route tuples to enough partitions that it runs out of space. This allows us to keep simple single-row partition INSERTs running quickly. Redesign The arrays in PartitionTupleRouting which stored the tuple translation maps have now been removed. These have been moved out into a PartitionRoutingInfo struct which is an additional field in ResultRelInfo. The find_all_inheritors() call still remains by far the slowest part of ExecSetupPartitionTupleRouting(). This commit just removes the other slow parts. In passing also rename the tuple translation maps from being ParentToChild and ChildToParent to being RootToPartition and PartitionToRoot. The old names mislead you into thinking that a partition of some sub-partitioned table would translate to the rowtype of the sub-partitioned table rather than the root partitioned table. Authors: David Rowley and Amit Langote, heavily revised by Álvaro Herrera Testing help from Jesper Pedersen and Kato Sho. Discussion: https://postgr.es/m/CAKJS1f_1RJyFquuCKRFHTdcXqoPX-PYqAd7nz=GVBwvGh4a6xA@mail.gmail.com
* Introduce notion of different types of slots (without implementing them).Andres Freund2018-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Upcoming work intends to allow pluggable ways to introduce new ways of storing table data. Accessing those table access methods from the executor requires TupleTableSlots to be carry tuples in the native format of such storage methods; otherwise there'll be a significant conversion overhead. Different access methods will require different data to store tuples efficiently (just like virtual, minimal, heap already require fields in TupleTableSlot). To allow that without requiring additional pointer indirections, we want to have different structs (embedding TupleTableSlot) for different types of slots. Thus different types of slots are needed, which requires adapting creators of slots. The slot that most efficiently can represent a type of tuple in an executor node will often depend on the type of slot a child node uses. Therefore we need to track the type of slot is returned by nodes, so parent slots can create slots based on that. Relatedly, JIT compilation of tuple deforming needs to know which type of slot a certain expression refers to, so it can create an appropriate deforming function for the type of tuple in the slot. But not all nodes will only return one type of slot, e.g. an append node will potentially return different types of slots for each of its subplans. Therefore add function that allows to query the type of a node's result slot, and whether it'll always be the same type (whether it's fixed). This can be queried using ExecGetResultSlotOps(). The scan, result, inner, outer type of slots are automatically inferred from ExecInitScanTupleSlot(), ExecInitResultSlot(), left/right subtrees respectively. If that's not correct for a node, that can be overwritten using new fields in PlanState. This commit does not introduce the actually abstracted implementation of different kind of TupleTableSlots, that will be left for a followup commit. The different types of slots introduced will, for now, still use the same backing implementation. While this already partially invalidates the big comment in tuptable.h, it seems to make more sense to update it later, when the different TupleTableSlot implementations actually exist. Author: Ashutosh Bapat and Andres Freund, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
* Rejigger materializing and fetching a HeapTuple from a slot.Andres Freund2018-11-15
| | | | | | | | | | | | | | | | | | | | | | | | | Previously materializing a slot always returned a HeapTuple. As current work aims to reduce the reliance on HeapTuples (so other storage systems can work efficiently), that needs to change. Thus split the tasks of materializing a slot (i.e. making it independent from the underlying storage / other memory contexts) from fetching a HeapTuple from the slot. For brevity, allow to fetch a HeapTuple from a slot and materializing the slot at the same time, controlled by a parameter. For now some callers of ExecFetchSlotHeapTuple, with materialize = true, expect that changes to the heap tuple will be reflected in the underlying slot. Those places will be adapted in due course, so while not pretty, that's OK for now. Also rename ExecFetchSlotTuple to ExecFetchSlotHeapTupleDatum and ExecFetchSlotTupleDatum to ExecFetchSlotHeapTupleDatum, as it's likely that future storage methods will need similar methods. There already is ExecFetchSlotMinimalTuple, so the new names make the naming scheme more coherent. Author: Ashutosh Bapat and Andres Freund, with changes by Amit Khandekar Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
* Improve some comments related to executor result relations.Tom Lane2018-10-17
| | | | | | | | es_leaf_result_relations doesn't exist; perhaps this was an old name for es_tuple_routing_result_relations, or maybe this comment has gone unmaintained through multiple rounds of whacking the code around. Related comment in execnodes.h was both obsolete and ungrammatical.
* Avoid O(N^2) cost in ExecFindRowMark().Tom Lane2018-10-08
| | | | | | | | | | | | | | | | | | | | If there are many ExecRowMark structs, we spent O(N^2) time in ExecFindRowMark during executor startup. Once upon a time this was not of great concern, but the addition of native partitioning has squeezed out enough other costs that this can become the dominant overhead in some use-cases for tables with many partitions. To fix, simply replace that List data structure with an array. This adds a little bit of cost to execCurrentOf(), but not much, and anyway that code path is neither of large importance nor very efficient now. If we ever decide it is a bottleneck, constructing a hash table for lookup-by-tableoid would likely be the thing to do. Per complaint from Amit Langote, though this is different from his fix proposal. Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Restore sane locking behavior during parallel query.Tom Lane2018-10-06
| | | | | | | | | | | | | | Commit 9a3cebeaa changed things so that parallel workers didn't obtain any lock of their own on tables they access. That was clearly a bad idea, but I'd mistakenly supposed that it was the intended end result of the series of patches for simplifying the executor's lock management. Undo that change in relation_open(), and adjust ExecOpenScanRelation() so that it gets the correct lock if inside a parallel worker. In passing, clean up some more obsolete comments about when locks are acquired. Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Remove more redundant relation locking during executor startup.Tom Lane2018-10-06
| | | | | | | | | | | | | | | | | We already have appropriate locks on every relation listed in the query's rangetable before we reach the executor. Take the next step in exploiting that knowledge by removing code that worries about taking locks on non-leaf result relations in a partitioned table. In particular, get rid of ExecLockNonLeafAppendTables and a stanza in InitPlan that asserts we already have locks on certain such tables. In passing, clean up some now-obsolete comments in InitPlan. Amit Langote, reviewed by David Rowley and Jesper Pedersen, and whacked around a bit more by me Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* In the executor, use an array of pointers to access the rangetable.Tom Lane2018-10-04
| | | | | | | | | | | | | | Instead of doing a lot of list_nth() accesses to es_range_table, create a flattened pointer array during executor startup and index into that to get at individual RangeTblEntrys. This eliminates one source of O(N^2) behavior with lots of partitions. (I'm not exactly convinced that it's the most important source, but it's an easy one to fix.) Amit Langote and David Rowley Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Centralize executor's opening/closing of Relations for rangetable entries.Tom Lane2018-10-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | Create an array estate->es_relations[] paralleling the es_range_table, and store references to Relations (relcache entries) there, so that any given RT entry is opened and closed just once per executor run. Scan nodes typically still call ExecOpenScanRelation, but ExecCloseScanRelation is no more; relation closing is now done centrally in ExecEndPlan. This is slightly more complex than one would expect because of the interactions with relcache references held in ResultRelInfo nodes. The general convention is now that ResultRelInfo->ri_RelationDesc does not represent a separate relcache reference and so does not need to be explicitly closed; but there is an exception for ResultRelInfos in the es_trig_target_relations list, which are manufactured by ExecGetTriggerResultRel and have to be cleaned up by ExecCleanUpTriggerState. (That much was true all along, but these ResultRelInfos are now more different from others than they used to be.) To allow the partition pruning logic to make use of es_relations[] rather than having its own relcache references, adjust PartitionedRelPruneInfo to store an RT index rather than a relation OID. Amit Langote, reviewed by David Rowley and Jesper Pedersen, some mods by me Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Change executor to just Assert that table locks were already obtained.Tom Lane2018-10-03
| | | | | | | | | | | | | | | | | | | | | | Instead of locking tables during executor startup, just Assert that suitable locks were obtained already during the parse/plan pipeline (or re-obtained by the plan cache). This must be so, else we have a hazard that concurrent DDL has invalidated the plan. This is pretty inefficient as well as undercommented, but it's all going to go away shortly, so I didn't try hard. This commit is just another attempt to use the buildfarm to see if we've missed anything in the plan to simplify the executor's table management. Note that the change needed here in relation_open() exposes that parallel workers now really are accessing tables without holding any lock of their own, whereas they were not doing that before this commit. This does not give me a warm fuzzy feeling about that aspect of parallel query; it does not seem like a good design, and we now know that it's had exactly no actual testing. I think that we should modify parallel query so that that change can be reverted. Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Fix issues around EXPLAIN with JIT.Andres Freund2018-10-03
| | | | | | | | | | | | | | | | | I (Andres) was more than a bit hasty in committing 33001fd7a7072d48327 after last minute changes, leading to a number of problems (jit output was only shown for JIT in parallel workers, and just EXPLAIN without ANALYZE didn't work). Lukas luckily found these issues quickly. Instead of combining instrumentation in in standard_ExecutorEnd(), do so on demand in the new ExplainPrintJITSummary(). Also update a documentation example of the JIT output, changed in 52050ad8ebec8d831. Author: Lukas Fittl, with minor changes by me Discussion: https://postgr.es/m/CAP53PkxmgJht69pabxBXJBM+0oc6kf3KHMborLP7H2ouJ0CCtQ@mail.gmail.com Backpatch: 11, where JIT compilation was introduced
* Change rewriter/planner/executor/plancache to depend on RTE rellockmode.Tom Lane2018-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | Instead of recomputing the required lock levels in all these places, just use what commit fdba460a2 made the parser store in the RTE fields. This already simplifies the code measurably in these places, and follow-on changes will remove a bunch of no-longer-needed infrastructure. In a few cases, this change causes us to acquire a higher lock level than we did before. This is OK primarily because said higher lock level should've been acquired already at query parse time; thus, we're saving a useless extra trip through the shared lock manager to acquire a lesser lock alongside the original lock. The only known exception to this is that re-execution of a previously planned SELECT FOR UPDATE/SHARE query, for a table that uses ROW_MARK_REFERENCE or ROW_MARK_COPY methods, might have gotten only AccessShareLock before. Now it will get RowShareLock like the first execution did, which seems fine. While there's more to do, push it in this state anyway, to let the buildfarm help verify that nothing bad happened. Amit Langote, reviewed by David Rowley and Jesper Pedersen, and whacked around a bit more by me Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Use slots more widely in tuple mapping code and make naming more consistent.Andres Freund2018-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | It's inefficient to use a single slot for mapping between tuple descriptors for multiple tuples, as previously done when using ConvertPartitionTupleSlot(), as that means the slot's tuple descriptors change for every tuple. Previously we also, via ConvertPartitionTupleSlot(), built new tuples after the mapping even in cases where we, immediately afterwards, access individual columns again. Refactor the code so one slot, on demand, is used for each partition. That avoids having to change the descriptor (and allows to use the more efficient "fixed" tuple slots). Then use slot->slot mapping, to avoid unnecessarily forming a tuple. As the naming between the tuple and slot mapping functions wasn't consistent, rename them to execute_attr_map_{tuple,slot}. It's likely that we'll also rename convert_tuples_by_* to denote that these functions "only" build a map, but that's left for later. Author: Amit Khandekar and Amit Langote, editorialized by me Reviewed-By: Amit Langote, Amit Khandekar, Andres Freund Discussion: https://postgr.es/m/CAJ3gD9fR0wRNeAE8VqffNTyONS_UfFPRpqxhnD9Q42vZB+Jvpg@mail.gmail.com https://postgr.es/m/e4f9d743-cd4b-efb0-7574-da21d86a7f36%40lab.ntt.co.jp Backpatch: -
* Create an RTE field to record the query's lock mode for each relation.Tom Lane2018-09-30
| | | | | | | | | | | | | | | | | | | | | | | | Add RangeTblEntry.rellockmode, which records the appropriate lock mode for each RTE_RELATION rangetable entry (either AccessShareLock, RowShareLock, or RowExclusiveLock depending on the RTE's role in the query). This patch creates the field and makes all creators of RTE nodes fill it in reasonably, but for the moment nothing much is done with it. The plan is to replace assorted post-parser logic that re-determines the right lockmode to use with simple uses of rte->rellockmode. For now, just add Asserts in each of those places that the rellockmode matches what they are computing today. (In some cases the match isn't perfect, so the Asserts are weaker than you might expect; but this seems OK, as per discussion.) This passes check-world for me, but it seems worth pushing in this state to see if the buildfarm finds any problems in cases I failed to test. catversion bump due to change of stored rules. Amit Langote, reviewed by David Rowley and Jesper Pedersen, and whacked around a bit more by me Discussion: https://postgr.es/m/468c85d9-540e-66a2-1dde-fec2b741e688@lab.ntt.co.jp
* Split ExecStoreTuple into ExecStoreHeapTuple and ExecStoreBufferHeapTuple.Andres Freund2018-09-25
| | | | | | | | | | | | | | | | | | | | Upcoming changes introduce further types of tuple table slots, in preparation of making table storage pluggable. New storage methods will have different representation of tuples, therefore the slot accessor should refer explicitly to heap tuples. Instead of just renaming the functions, split it into one function that accepts heap tuples not residing in buffers, and one accepting ones in buffers. Previously one function was used for both, but that was a bit awkward already, and splitting will allow us to represent slot types for tuples in buffers and normal memory separately. This is split out from the patch introducing abstract slots, as this largely consists out of mechanical changes. Author: Ashutosh Bapat Reviewed-By: Andres Freund Discussion: https://postgr.es/m/20180220224318.gw4oe5jadhpmcdnm@alap3.anarazel.de
* Collect JIT instrumentation from workers.Andres Freund2018-09-25
| | | | | | | | | | | | | | | | Previously, when using parallel query, EXPLAIN (ANALYZE)'s JIT compilation timings did not include the overhead from doing so on the workers. Fix that. We do so by simply aggregating the cost of doing JIT compilation on workers and the leader together. Arguably that's not quite accurate, because the total time spend doing so is spent in parallel - but it's hard to do much better. For additional detail, when VERBOSE is specified, the stats for workers are displayed separately. Author: Amit Khandekar and Andres Freund Discussion: https://postgr.es/m/CAJ3gD9eLrz51RK_gTkod+71iDcjpB_N8eC6vU2AW-VicsAERpQ@mail.gmail.com Backpatch: 11-
* Fix failure with initplans used conditionally during EvalPlanQual rechecks.Tom Lane2018-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The EvalPlanQual machinery assumes that any initplans (that is, uncorrelated sub-selects) used during an EPQ recheck would have already been evaluated during the main query; this is implicit in the fact that execPlan pointers are not copied into the EPQ estate's es_param_exec_vals. But it's possible for that assumption to fail, if the initplan is only reached conditionally. For example, a sub-select inside a CASE expression could be reached during a recheck when it had not been previously, if the CASE test depends on a column that was just updated. This bug is old, appearing to date back to my rewrite of EvalPlanQual in commit 9f2ee8f28, but was not detected until Kyle Samson reported a case. To fix, force all not-yet-evaluated initplans used within the EPQ plan subtree to be evaluated at the start of the recheck, before entering the EPQ environment. This could be inefficient, if such an initplan is expensive and goes unused again during the recheck --- but that's piling one layer of improbability atop another. It doesn't seem worth adding more complexity to prevent that, at least not in the back branches. It was convenient to use the new-in-v11 ExecEvalParamExecParams function to implement this, but I didn't like either its name or the specifics of its API, so revise that. Back-patch all the way. Rather than rewrite the patch to avoid depending on bms_next_member() in the oldest branches, I chose to back-patch that function into 9.4 and 9.3. (This isn't the first time back-patches have needed that, and it exhausted my patience.) I also chose to back-patch some test cases added by commits 71404af2a and 342a1ffa2 into 9.4 and 9.3, so that the 9.x versions of eval-plan-qual.spec are all the same. Andrew Gierth diagnosed the problem and contributed the added test cases, though the actual code changes are by me. Discussion: https://postgr.es/m/A033A40A-B234-4324-BE37-272279F7B627@tripadvisor.com
* Prohibit shutting down resources if there is a possibility of back up.Amit Kapila2018-08-13
| | | | | | | | | | | | | | | Currently, we release the asynchronous resources as soon as it is evident that no more rows will be needed e.g. when a Limit is filled. This can be problematic especially for custom and foreign scans where we can scan backward. Fix that by disallowing the shutting down of resources in such cases. Reported-by: Robert Haas Analysed-by: Robert Haas and Amit Kapila Author: Amit Kapila Reviewed-by: Robert Haas Backpatch-through: 9.6 where this code was introduced Discussion: https://postgr.es/m/86137f17-1dfb-42f9-7421-82fd786b04a1@anayrat.info
* Revert changes in execMain.c from commit 16828d5c0273bAndrew Dunstan2018-08-10
| | | | | | | | | | These changes were put in at some stage of the development process, but are unnecessary and should not have made it into the final patch. Mea culpa. Per gripe from Andreas Freund Backpatch to REL_11_STABLE
* LLVMJIT: Release JIT context after running ExprContext shutdown callbacks.Andres Freund2018-07-25
| | | | | | | | | | | | Due to inlining it previously was possible that an ExprContext's shutdown callback pointed to a JITed function. As the JIT context previously was shut down before the shutdown callbacks were called, that could lead to segfaults. Fix the ordering. Reported-By: Dmitry Dolgov Author: Andres Freund Discussion: https://postgr.es/m/CA+q6zcWO7CeAJtHBxgcHn_hj+PenM=tvG0RJ93X1uEJ86+76Ug@mail.gmail.com Backpatch: 11-, where JIT compilation was added
* pgindent run prior to branchingAndrew Dunstan2018-06-30
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* Don't needlessly check the partition contraint twiceAlvaro Herrera2018-06-11
| | | | | | | | | | | | | | | | | | | | | Starting with commit f0e44751d717, ExecConstraints was in charge of running the partition constraint; commit 19c47e7c8202 modified that so that caller could request to skip that checking depending on some conditions, but that commit and 15ce775faa42 together introduced a small bug there which caused ExecInsert to request skipping the constraint check but have this not be honored -- in effect doing the check twice. This could have been fixed in a very small patch, but on further analysis of the involved function and its callsites, it turns out to be simpler to give the responsibility of checking the partition constraint fully to the caller, and return ExecConstraints to its original (pre-partitioning) shape where it only checked tuple descriptor-related constraints. Each caller must do partition constraint checking on its own schedule, which is more convenient after commit 2f178441044 anyway. Reported-by: David Rowley Author: David Rowley, Álvaro Herrera Reviewed-by: Amit Langote, Amit Khandekar, Simon Riggs Discussion: https://postgr.es/m/CAKJS1f8w8+awsxgea8wt7_UX8qzOQ=Tm1LD+U1fHqBAkXxkW2w@mail.gmail.com
* Fix typoPeter Eisentraut2018-06-08
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* Clean up warnings from -Wimplicit-fallthrough.Tom Lane2018-05-01
| | | | | | | | | | | | | | | | | | | | | | | | | Recent gcc can warn about switch-case fall throughs that are not explicitly labeled as intentional. This seems like a good thing, so clean up the warnings exposed thereby by labeling all such cases with comments that gcc will recognize. In files that already had one or more suitable comments, I generally matched the existing style of those. Otherwise I went with /* FALLTHROUGH */, which is one of the spellings approved at the more-restrictive-than-default level -Wimplicit-fallthrough=4. (At the default level you can also spell it /* FALL ?THRU */, and it's not picky about case. What you can't do is include additional text in the same comment, so some existing comments containing versions of this aren't good enough.) Testing with gcc 8.0.1 (Fedora 28's current version), I found that I also had to put explicit "break"s after elog(ERROR) or ereport(ERROR); apparently, for this purpose gcc doesn't recognize that those don't return. That seems like possibly a gcc bug, but it's fine because in most places we did that anyway; so this amounts to a visit from the style police. Discussion: https://postgr.es/m/15083.1525207729@sss.pgh.pa.us
* Post-feature-freeze pgindent run.Tom Lane2018-04-26
| | | | Discussion: https://postgr.es/m/15719.1523984266@sss.pgh.pa.us
* Reorganize partitioning codeAlvaro Herrera2018-04-14
| | | | | | | | | | | | | | | | | | | | | | There's been a massive addition of partitioning code in PostgreSQL 11, with little oversight on its placement, resulting in a catalog/partition.c with poorly defined boundaries and responsibilities. This commit tries to set a couple of distinct modules to separate things a little bit. There are no code changes here, only code movement. There are three new files: src/backend/utils/cache/partcache.c src/include/partitioning/partdefs.h src/include/utils/partcache.h The previous arrangement of #including catalog/partition.h almost everywhere is no more. Authors: Amit Langote and Álvaro Herrera Discussion: https://postgr.es/m/98e8d509-790a-128c-be7f-e48a5b2d8d97@lab.ntt.co.jp https://postgr.es/m/11aa0c50-316b-18bb-722d-c23814f39059@lab.ntt.co.jp https://postgr.es/m/143ed9a4-6038-76d4-9a55-502035815e68@lab.ntt.co.jp https://postgr.es/m/20180413193503.nynq7bnmgh6vs5vm@alvherre.pgsql
* Revert MERGE patchSimon Riggs2018-04-12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commits d204ef63776b8a00ca220adec23979091564e465, 83454e3c2b28141c0db01c7d2027e01040df5249 and a few more commits thereafter (complete list at the end) related to MERGE feature. While the feature was fully functional, with sufficient test coverage and necessary documentation, it was felt that some parts of the executor and parse-analyzer can use a different design and it wasn't possible to do that in the available time. So it was decided to revert the patch for PG11 and retry again in the future. Thanks again to all reviewers and bug reporters. List of commits reverted, in reverse chronological order: f1464c5380 Improve parse representation for MERGE ddb4158579 MERGE syntax diagram correction 530e69e59b Allow cpluspluscheck to pass by renaming variable 01b88b4df5 MERGE minor errata 3af7b2b0d4 MERGE fix variable warning in non-assert builds a5d86181ec MERGE INSERT allows only one VALUES clause 4b2d44031f MERGE post-commit review 4923550c20 Tab completion for MERGE aa3faa3c7a WITH support in MERGE 83454e3c2b New files for MERGE d204ef6377 MERGE SQL Command following SQL:2016 Author: Pavan Deolasee Reviewed-by: Michael Paquier
* Raise error when affecting tuple moved into different partition.Andres Freund2018-04-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an update moves a row between partitions (supported since 2f178441044b), our normal logic for following update chains in READ COMMITTED mode doesn't work anymore. Cross partition updates are modeled as an delete from the old and insert into the new partition. No ctid chain exists across partitions, and there's no convenient space to introduce that link. Not throwing an error in a partitioned context when one would have been thrown without partitioning is obviously problematic. This commit introduces infrastructure to detect when a tuple has been moved, not just plainly deleted. That allows to throw an error when encountering a deletion that's actually a move, while attempting to following a ctid chain. The row deleted as part of a cross partition update is marked by pointing it's t_ctid to an invalid block, instead of self as a normal update would. That was deemed to be the least invasive and most future proof way to represent the knowledge, given how few infomask bits are there to be recycled (there's also some locking issues with using infomask bits). External code following ctid chains should be updated to check for moved tuples. The most likely consequence of not doing so is a missed error. Author: Amul Sul, editorialized by me Reviewed-By: Amit Kapila, Pavan Deolasee, Andres Freund, Robert Haas Discussion: http://postgr.es/m/CAAJ_b95PkwojoYfz0bzXU8OokcTVGzN6vYGCNVUukeUDrnF3dw@mail.gmail.com
* Allow insert and update tuple routing and COPY for foreign tables.Robert Haas2018-04-06
| | | | | | | | | | | Also enable this for postgres_fdw. Etsuro Fujita, based on an earlier patch by Amit Langote. The larger patch series of which this is a part has been reviewed by Amit Langote, David Fetter, Maksim Milyutin, Álvaro Herrera, Stephen Frost, and me. Minor documentation changes to the final version by me. Discussion: http://postgr.es/m/29906a26-da12-8c86-4fb9-d8f88442f2b9@lab.ntt.co.jp
* MERGE SQL Command following SQL:2016Simon Riggs2018-04-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MERGE performs actions that modify rows in the target table using a source table or query. MERGE provides a single SQL statement that can conditionally INSERT/UPDATE/DELETE rows a task that would other require multiple PL statements. e.g. MERGE INTO target AS t USING source AS s ON t.tid = s.sid WHEN MATCHED AND t.balance > s.delta THEN UPDATE SET balance = t.balance - s.delta WHEN MATCHED THEN DELETE WHEN NOT MATCHED AND s.delta > 0 THEN INSERT VALUES (s.sid, s.delta) WHEN NOT MATCHED THEN DO NOTHING; MERGE works with regular and partitioned tables, including column and row security enforcement, as well as support for row, statement and transition triggers. MERGE is optimized for OLTP and is parameterizable, though also useful for large scale ETL/ELT. MERGE is not intended to be used in preference to existing single SQL commands for INSERT, UPDATE or DELETE since there is some overhead. MERGE can be used statically from PL/pgSQL. MERGE does not yet support inheritance, write rules, RETURNING clauses, updatable views or foreign tables. MERGE follows SQL Standard per the most recent SQL:2016. Includes full tests and documentation, including full isolation tests to demonstrate the concurrent behavior. This version written from scratch in 2017 by Simon Riggs, using docs and tests originally written in 2009. Later work from Pavan Deolasee has been both complex and deep, leaving the lead author credit now in his hands. Extensive discussion of concurrency from Peter Geoghegan, with thanks for the time and effort contributed. Various issues reported via sqlsmith by Andreas Seltenreich Authors: Pavan Deolasee, Simon Riggs Reviewer: Peter Geoghegan, Amit Langote, Tomas Vondra, Simon Riggs Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
* Revert "Modified files for MERGE"Simon Riggs2018-04-02
| | | | This reverts commit 354f13855e6381d288dfaa52bcd4f2cb0fd4a5eb.
* Modified files for MERGESimon Riggs2018-04-02
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* Fast ALTER TABLE ADD COLUMN with a non-NULL defaultAndrew Dunstan2018-03-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | Currently adding a column to a table with a non-NULL default results in a rewrite of the table. For large tables this can be both expensive and disruptive. This patch removes the need for the rewrite as long as the default value is not volatile. The default expression is evaluated at the time of the ALTER TABLE and the result stored in a new column (attmissingval) in pg_attribute, and a new column (atthasmissing) is set to true. Any existing row when fetched will be supplied with the attmissingval. New rows will have the supplied value or the default and so will never need the attmissingval. Any time the table is rewritten all the atthasmissing and attmissingval settings for the attributes are cleared, as they are no longer needed. The most visible code change from this is in heap_attisnull, which acquires a third TupleDesc argument, allowing it to detect a missing value if there is one. In many cases where it is known that there will not be any (e.g. catalog relations) NULL can be passed for this argument. Andrew Dunstan, heavily modified from an original patch from Serge Rielau. Reviewed by Tom Lane, Andres Freund, Tomas Vondra and David Rowley. Discussion: https://postgr.es/m/31e2e921-7002-4c27-59f5-51f08404c858@2ndQuadrant.com
* Handle INSERT .. ON CONFLICT with partitioned tablesAlvaro Herrera2018-03-26
| | | | | | | | | | | | Commit eb7ed3f30634 enabled unique constraints on partitioned tables, but one thing that was not working properly is INSERT/ON CONFLICT. This commit introduces a new node keeps state related to the ON CONFLICT clause per partition, and fills it when that partition is about to be used for tuple routing. Author: Amit Langote, Álvaro Herrera Reviewed-by: Etsuro Fujita, Pavan Deolasee Discussion: https://postgr.es/m/20180228004602.cwdyralmg5ejdqkq@alvherre.pgsql
* Remove useless if-test.Tom Lane2018-03-25
| | | | | | Coverity complained that this check is pointless, and it's right. There is no case where we'd call ExecutorStart with a null plannedstmt, and if we did, it'd have crashed before here. Thinko in commit cc415a56d.
* Basic planner and executor integration for JIT.Andres Freund2018-03-22
| | | | | | | | | | | | | | | | | | | | | This adds simple cost based plan time decision about whether JIT should be performed. jit_above_cost, jit_optimize_above_cost are compared with the total cost of a plan, and if the cost is above them JIT is performed / optimization is performed respectively. For that PlannedStmt and EState have a jitFlags (es_jit_flags) field that stores information about what JIT operations should be performed. EState now also has a new es_jit field, which can store a JitContext. When there are no errors the context is released in standard_ExecutorEnd(). It is likely that the default values for jit_[optimize_]above_cost will need to be adapted further, but in my test these values seem to work reasonably. Author: Andres Freund, with feedback by Peter Eisentraut Discussion: https://postgr.es/m/20170901064131.tazjxwus3k2w3ybh@alap3.anarazel.de
* Allow tupleslots to have a fixed tupledesc, use in executor nodes.Andres Freund2018-02-16
| | | | | | | | | | | | | | | | | | | | | The reason for doing so is that it will allow expression evaluation to optimize based on the underlying tupledesc. In particular it will allow to JIT tuple deforming together with the expression itself. For that expression initialization needs to be moved after the relevant slots are initialized - mostly unproblematic, except in the case of nodeWorktablescan.c. After doing so there's no need for ExecAssignResultType() and ExecAssignResultTypeFromTL() anymore, as all former callers have been converted to create a slot with a fixed descriptor. When creating a slot with a fixed descriptor, tts_values/isnull can be allocated together with the main slot, reducing allocation overhead and increasing cache density a bit. Author: Andres Freund Discussion: https://postgr.es/m/20171206093717.vqdxe5icqttpxs3p@alap3.anarazel.de
* Avoid listing the same ResultRelInfo in more than one EState list.Robert Haas2018-02-08
| | | | | | | | Doing so causes EXPLAIN ANALYZE to show trigger statistics multiple times. Commit 2f178441044be430f6b4d626e4dae68a9a6f6cec seems to be to blame for this. Amit Langote, revieed by Amit Khandekar, Etsuro Fujita, and me.