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* Phase 2 pgindent run for v12.Tom Lane2019-05-22
| | | | | | | | | Switch to 2.1 version of pg_bsd_indent. This formats multiline function declarations "correctly", that is with additional lines of parameter declarations indented to match where the first line's left parenthesis is. Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
* Collations with nondeterministic comparisonPeter Eisentraut2019-03-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a flag "deterministic" to collations. If that is false, such a collation disables various optimizations that assume that strings are equal only if they are byte-wise equal. That then allows use cases such as case-insensitive or accent-insensitive comparisons or handling of strings with different Unicode normal forms. This functionality is only supported with the ICU provider. At least glibc doesn't appear to have any locales that work in a nondeterministic way, so it's not worth supporting this for the libc provider. The term "deterministic comparison" in this context is from Unicode Technical Standard #10 (https://unicode.org/reports/tr10/#Deterministic_Comparison). This patch makes changes in three areas: - CREATE COLLATION DDL changes and system catalog changes to support this new flag. - Many executor nodes and auxiliary code are extended to track collations. Previously, this code would just throw away collation information, because the eventually-called user-defined functions didn't use it since they only cared about equality, which didn't need collation information. - String data type functions that do equality comparisons and hashing are changed to take the (non-)deterministic flag into account. For comparison, this just means skipping various shortcuts and tie breakers that use byte-wise comparison. For hashing, we first need to convert the input string to a canonical "sort key" using the ICU analogue of strxfrm(). Reviewed-by: Daniel Verite <daniel@manitou-mail.org> Reviewed-by: Peter Geoghegan <pg@bowt.ie> Discussion: https://www.postgresql.org/message-id/flat/1ccc668f-4cbc-0bef-af67-450b47cdfee7@2ndquadrant.com
* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Fix EXPLAIN ANALYZE output for Parallel Hash.Andres Freund2018-01-01
| | | | | | | | | | | | | | In a race case, EXPLAIN ANALYZE could fail to display correct nbatch and size information. Refactor so that participants report only on batches they worked on rather than trying to report on all of them, and teach explain.c to consider the HashInstrumentation object from all participants instead of picking the first one it can find. This should fix an occasional build farm failure in the "join" regression test. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/30219.1514428346%40sss.pgh.pa.us
* Add parallel-aware hash joins.Andres Freund2017-12-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce parallel-aware hash joins that appear in EXPLAIN plans as Parallel Hash Join with Parallel Hash. While hash joins could already appear in parallel queries, they were previously always parallel-oblivious and had a partial subplan only on the outer side, meaning that the work of the inner subplan was duplicated in every worker. After this commit, the planner will consider using a partial subplan on the inner side too, using the Parallel Hash node to divide the work over the available CPU cores and combine its results in shared memory. If the join needs to be split into multiple batches in order to respect work_mem, then workers process different batches as much as possible and then work together on the remaining batches. The advantages of a parallel-aware hash join over a parallel-oblivious hash join used in a parallel query are that it: * avoids wasting memory on duplicated hash tables * avoids wasting disk space on duplicated batch files * divides the work of building the hash table over the CPUs One disadvantage is that there is some communication between the participating CPUs which might outweigh the benefits of parallelism in the case of small hash tables. This is avoided by the planner's existing reluctance to supply partial plans for small scans, but it may be necessary to estimate synchronization costs in future if that situation changes. Another is that outer batch 0 must be written to disk if multiple batches are required. A potential future advantage of parallel-aware hash joins is that right and full outer joins could be supported, since there is a single set of matched bits for each hashtable, but that is not yet implemented. A new GUC enable_parallel_hash is defined to control the feature, defaulting to on. Author: Thomas Munro Reviewed-By: Andres Freund, Robert Haas Tested-By: Rafia Sabih, Prabhat Sahu Discussion: https://postgr.es/m/CAEepm=2W=cOkiZxcg6qiFQP-dHUe09aqTrEMM7yJDrHMhDv_RA@mail.gmail.com https://postgr.es/m/CAEepm=37HKyJ4U6XOLi=JgfSHM3o6B-GaeO-6hkOmneTDkH+Uw@mail.gmail.com
* Try again to fix accumulation of parallel worker instrumentation.Robert Haas2017-12-19
| | | | | | | | | | | | | | | | | When a Gather or Gather Merge node is started and stopped multiple times, accumulate instrumentation data only once, at the end, instead of after each execution, to avoid recording inflated totals. Commit 778e78ae9fa51e58f41cbdc72b293291d02d8984, the previous attempt at a fix, instead reset the state after every execution, which worked for the general instrumentation data but had problems for the additional instrumentation specific to Sort and Hash nodes. Report by hubert depesz lubaczewski. Analysis and fix by Amit Kapila, following a design proposal from Thomas Munro, with a comment tweak by me. Discussion: http://postgr.es/m/20171127175631.GA405@depesz.com
* Fix EXPLAIN ANALYZE of hash join when the leader doesn't participate.Andres Freund2017-12-05
| | | | | | | | | | | | | | | | | | | | If a hash join appears in a parallel query, there may be no hash table available for explain.c to inspect even though a hash table may have been built in other processes. This could happen either because parallel_leader_participation was set to off or because the leader happened to hit the end of the outer relation immediately (even though the complete relation is not empty) and decided not to build the hash table. Commit bf11e7ee introduced a way for workers to exchange instrumentation via the DSM segment for Sort nodes even though they are not parallel-aware. This commit does the same for Hash nodes, so that explain.c has a way to find instrumentation data from an arbitrary participant that actually built the hash table. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm%3D3DUQC2-z252N55eOcZBer6DPdM%3DFzrxH9dZc5vYLsjaA%40mail.gmail.com
* Move ExecProcNode from dispatch to function pointer based model.Andres Freund2017-07-30
| | | | | | | | | | | | | | | | | | | | | | This allows us to add stack-depth checks the first time an executor node is called, and skip that overhead on following calls. Additionally it yields a nice speedup. While it'd probably have been a good idea to have that check all along, it has become more important after the new expression evaluation framework in b8d7f053c5c2bf2a7e - there's no stack depth check in common paths anymore now. We previously relied on ExecEvalExpr() being executed somewhere. We should move towards that model for further routines, but as this is required for v10, it seems better to only do the necessary (which already is quite large). Author: Andres Freund, Tom Lane Reported-By: Julien Rouhaud Discussion: https://postgr.es/m/22833.1490390175@sss.pgh.pa.us https://postgr.es/m/b0af9eaa-130c-60d0-9e4e-7a135b1e0c76@dalibo.com
* Phase 2 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* pgindent run before PG 9.1 beta 1.Bruce Momjian2011-04-10
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* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Support RIGHT and FULL OUTER JOIN in hash joins.Tom Lane2010-12-30
| | | | | | | | | | | | | | | | | | | | | | This is advantageous first because it allows us to hash the smaller table regardless of the outer-join type, and second because hash join can be more flexible than merge join in dealing with arbitrary join quals in a FULL join. For merge join all the join quals have to be mergejoinable, but hash join will work so long as there's at least one hashjoinable qual --- the others can be any condition. (This is true essentially because we don't keep per-inner-tuple match flags in merge join, while hash join can do so.) To do this, we need a has-it-been-matched flag for each tuple in the hashtable, not just one for the current outer tuple. The key idea that makes this practical is that we can store the match flag in the tuple's infomask, since there are lots of bits there that are of no interest for a MinimalTuple. So we aren't increasing the size of the hashtable at all for the feature. To write this without turning the hash code into even more of a pile of spaghetti than it already was, I rewrote ExecHashJoin in a state-machine style, similar to ExecMergeJoin. Other than that decision, it was pretty straightforward.
* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* Make NestLoop plan nodes pass outer-relation variables into their innerTom Lane2010-07-12
| | | | | | | | | | | | relation using the general PARAM_EXEC executor parameter mechanism, rather than the ad-hoc kluge of passing the outer tuple down through ExecReScan. The previous method was hard to understand and could never be extended to handle parameters coming from multiple join levels. This patch doesn't change the set of possible plans nor have any significant performance effect, but it's necessary infrastructure for future generalization of the concept of an inner indexscan plan. ExecReScan's second parameter is now unused, so it's removed.
* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Remove no-longer-needed ExecCountSlots infrastructure.Tom Lane2009-09-27
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* Optimize multi-batch hash joins when the outer relation has a nonuniformTom Lane2009-03-21
| | | | | | | | | distribution, by creating a special fast path for the (first few) most common values of the outer relation. Tuples having hashvalues matching the MCVs are effectively forced to be in the first batch, so that we never write them out to the batch temp files. Bryce Cutt and Ramon Lawrence, with some editorialization by me.
* Update copyright for 2009.Bruce Momjian2009-01-01
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* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Add support for cross-type hashing in hash index searches and hash joins.Tom Lane2007-01-30
| | | | | | Hashing for aggregation purposes still needs work, so it's not time to mark any cross-type operators as hashable for general use, but these cases work if the operators are so marked by hand in the system catalogs.
* Improve hash join to discard input tuples immediately if they can'tTom Lane2007-01-28
| | | | | | match because they contain a null join key (and the join operator is known strict). Improves performance significantly when the inner relation contains a lot of nulls, as per bug #2930.
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Convert hash join code to use MinimalTuple format in tuple hash tableTom Lane2006-06-27
| | | | and batch files. Should reduce memory and I/O demands for such joins.
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Extend the ExecInitNode API so that plan nodes receive a set of flagTom Lane2006-02-28
| | | | | | | | | | | | bits indicating which optional capabilities can actually be exercised at runtime. This will allow Sort and Material nodes, and perhaps later other nodes, to avoid unnecessary overhead in common cases. This commit just adds the infrastructure and arranges to pass the correct flag values down to plan nodes; none of the actual optimizations are here yet. I'm committing this separately in case anyone wants to measure the added overhead. (It should be negligible.) Simon Riggs and Tom Lane
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Create a new 'MultiExecProcNode' call API for plan nodes that don'tTom Lane2005-04-16
| | | | | | | return just a single tuple at a time. Currently the only such node type is Hash, but I expect we will soon have indexscans that can return tuple bitmaps. A side benefit is that EXPLAIN ANALYZE now shows the correct tuple count for a Hash node.
* Revise hash join code so that we can increase the number of batchesTom Lane2005-03-06
| | | | | | | on-the-fly, and thereby avoid blowing out memory when the planner has underestimated the hash table size. Hash join will now obey the work_mem limit with some faithfulness. Per my recent proposal (hash aggregate part isn't done yet though).
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-31
| | | | | | | | Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
* Update copyright to 2004.Bruce Momjian2004-08-29
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* make sure the $Id tags are converted to $PostgreSQL as well ...PostgreSQL Daemon2003-11-29
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* Update copyrights to 2003.Bruce Momjian2003-08-04
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* pgindent run.Bruce Momjian2003-08-04
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* Revise hash join and hash aggregation code to use the same datatype-Tom Lane2003-06-22
| | | | | | | | specific hash functions used by hash indexes, rather than the old not-datatype-aware ComputeHashFunc routine. This makes it safe to do hash joining on several datatypes that previously couldn't use hashing. The sets of datatypes that are hash indexable and hash joinable are now exactly the same, whereas before each had some that weren't in the other.
* Create a new file executor/execGrouping.c to centralize utility routinesTom Lane2003-01-10
| | | | shared by nodeGroup, nodeAgg, and soon nodeSubplan.
* Better solution to integer overflow problem in hash batch-numberTom Lane2002-12-30
| | | | | | | computation: reduce the bucket number mod nbatch. This changes the association between original bucket numbers and batches, but that doesn't matter. Minor other cleanups in hashjoin code to help centralize decisions.
* Phase 1 of read-only-plans project: cause executor state nodes to pointTom Lane2002-12-05
| | | | | | | | | | to plan nodes, not vice-versa. All executor state nodes now inherit from struct PlanState. Copying of plan trees has been simplified by not storing a list of SubPlans in Plan nodes (eliminating duplicate links). The executor still needs such a list, but it can build it during ExecutorStart since it has to scan the plan tree anyway. No initdb forced since no stored-on-disk structures changed, but you will need a full recompile because of node-numbering changes.
* Upgrade planner and executor to allow multiple hash keys for a hash join,Tom Lane2002-11-30
| | | | | | instead of only one. This should speed up planning (only one hash path to consider for a given pair of relations) as well as allow more effective hashing, when there are multiple hashable joinclauses.
* Phase 2 of hashed-aggregation project. nodeAgg.c now knows how to doTom Lane2002-11-06
| | | | hashed aggregation, but there's not yet planner support for it.
* Update copyright to 2002.Bruce Momjian2002-06-20
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* New pgindent run with fixes suggested by Tom. Patch manually reviewed,Bruce Momjian2001-11-05
| | | | initdb/regression tests pass.
* Another pgindent run. Fixes enum indenting, and improves #endifBruce Momjian2001-10-28
| | | | spacing. Also adds space for one-line comments.
* pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian2001-10-25
| | | | tests pass.
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