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I think we can reorder semi joins #120

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@Tmonster Tmonster commented Jan 25, 2024 •
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Need to fix the cardinality estimator so that semi and anti joins just do basic filtering.

To do this, we treat semi joins and anti joins like regular inner joins.
To make sure the left and right children are not flipped, we compare the left and right bindings from the original join to the left and right bindings of the recreated plan. If the children are flipped, we flip them back.

The cardinality estimates of semi and anti joins is as follows.

  • Take the cardinality of the left side and multiply it by 0.2. This is to simulate a filter, since it can be argued that a semi join is just a filter.

This method is also symmetrical, which means we don't have to change too much to the cardinality estimator.

Another heuristic was added for determining the number of distinct elements in a column as well. For integral type columns, if the maxVal - minVal is less than the distinct count measured by HLL, then DuckDB will prefer max - min as the distinct count.

I thought this was the source of a bad join order. Turns out that wasn't the case, but I think it is still a good join heuristic.

Tmonster added 21 commits January 25, 2024 17:59
@Tmonster
I think we can reorder semi joins
18b7e51
@Tmonster
I have access to the left and right sets and the join type. Now I sho…
77d503e 
…uld be able to reorder the semi join
@Tmonster
can now estimate a semi join to be 20% of the left table
34ad120
@Tmonster
have most everything working. some CEs not quite. Q05 tpch needs to b…
d8f8f9f 
…e looked at
@Tmonster
Merge remote-tracking branch 'upstream/main' into reorder-semi-and-an…
8e6b730 
…ti-joins
@Tmonster
some debugging statements
4ef7415
@Tmonster
make format-fix
d0e4892
@Tmonster
fix code where numerator relations were not properly being merged. Al…
9eecc85 
…so add better heuristics for determining a distinct count
@Tmonster
add cross product join type
2732612
@Tmonster
fix join is reorderabe function. generate enums
bd1d164
@Tmonster
pausing point
8be872d
@Tmonster
fix last join issue and better min/max stats help on distinct count
b9885f6
@Tmonster
remove min max stats changesg
e7eaf10
@Tmonster
add back in removed test
2183142
@Tmonster
pausing to work on adding benchmarks for ingestion
7f49a57
@Tmonster
trying to fix this column lifetime analyzer bug
206109e
@Tmonster
you can also change the bindings filters return. but that's not a goo…
830cdec 
…d idea
@Tmonster
remove changing what bindings filters return
dfab1b6
@Tmonster
check tests one more time. still need to figure out logical as of joi…
72cd1be 
…n reordering
@Tmonster
Merge branch 'reorder-semi-and-anti-joins' of github.com:Tmonster/duc…
990b296 
…kdb into reorder-semi-and-anti-joins
@Tmonster
make format-fix
333f252
@Tmonster Tmonster changed the base branch from main to feature March 28, 2024 13:03
@Tmonster Tmonster closed this Apr 8, 2024
Tmonster pushed a commit that referenced this pull request Dec 3, 2024
@Mytherin
Ensure checkpoint tasks complete on IO exceptions (duckdb#15089)
405ff1f 
I was investigating the following crash where a checkpoint task had its
underlying resources being destroyed while it was still running. The two
interesting threads are the following:

```
thread #1, name = 'duckling', stop reason = signal SIGTRAP
    frame #0: 0x0000ffff91bb71ec
    frame #1: 0x0000aaaad73a38e8 duckling`duckdb::InternalException::InternalException(this=<unavailable>, msg=<unavailable>) at exception.cpp:336:2
    frame #2: 0x0000aaaad786eb68 duckling`duckdb::unique_ptr<duckdb::RowGroup, std::default_delete<duckdb::RowGroup>, true>::operator*() const [inlined] duckdb::unique_ptr<duckdb::RowGroup, std::default_delete<duckdb::RowGroup>, true>::AssertNotNull(null=<unavailable>) at unique_ptr.hpp:25:10
    frame #3: 0x0000aaaad786eaf4 duckling`duckdb::unique_ptr<duckdb::RowGroup, std::default_delete<duckdb::RowGroup>, true>::operator*(this=0x0000aaacbb73e008) const at unique_ptr.hpp:34:4
    frame #4: 0x0000aaaad787abbc duckling`duckdb::CheckpointTask::ExecuteTask(this=0x0000aaabec92be60) at row_group_collection.cpp:732:21
    frame #5: 0x0000aaaad7756ea4 duckling`duckdb::BaseExecutorTask::Execute(this=0x0000aaabec92be60, mode=<unavailable>) at task_executor.cpp:72:3
    frame #6: 0x0000aaaad7757e28 duckling`duckdb::TaskScheduler::ExecuteForever(this=0x0000aaaafda30e10, marker=0x0000aaaafda164a8) at task_scheduler.cpp:189:32
    frame #7: 0x0000ffff91a031fc
    frame #8: 0x0000ffff91c0d5c8

thread #120, stop reason = signal 0
    frame #0: 0x0000ffff91c71c24
    frame #1: 0x0000ffff91e1264c
    frame #2: 0x0000ffff91e01888
    frame #3: 0x0000ffff91e018f8
    frame #4: 0x0000ffff91e01c10
    frame #5: 0x0000ffff91e05afc
    frame #6: 0x0000ffff91e05e70
    frame #7: 0x0000aaaad784b63c duckling`duckdb::RowGroup::~RowGroup() [inlined] std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release(this=<unavailable>) at shared_ptr_base.h:184:10
    frame #8: 0x0000aaaad784b5b4 duckling`duckdb::RowGroup::~RowGroup() [inlined] std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count(this=<unavailable>) at shared_ptr_base.h:705:11
    frame #9: 0x0000aaaad784b5ac duckling`duckdb::RowGroup::~RowGroup() [inlined] std::__shared_ptr<duckdb::ColumnData, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr(this=<unavailable>) at shared_ptr_base.h:1154:31
    frame #10: 0x0000aaaad784b5ac duckling`duckdb::RowGroup::~RowGroup() [inlined] duckdb::shared_ptr<duckdb::ColumnData, true>::~shared_ptr(this=<unavailable>) at shared_ptr_ipp.hpp:115:24
    frame #11: 0x0000aaaad784b5ac duckling`duckdb::RowGroup::~RowGroup() [inlined] void std::_Destroy<duckdb::shared_ptr<duckdb::ColumnData, true>>(__pointer=<unavailable>) at stl_construct.h:151:19
    frame #12: 0x0000aaaad784b5ac duckling`duckdb::RowGroup::~RowGroup() [inlined] void std::_Destroy_aux<false>::__destroy<duckdb::shared_ptr<duckdb::ColumnData, true>*>(__first=<unavailable>, __last=<unavailable>) at stl_construct.h:163:6
    frame #13: 0x0000aaaad784b5a0 duckling`duckdb::RowGroup::~RowGroup() [inlined] void std::_Destroy<duckdb::shared_ptr<duckdb::ColumnData, true>*>(__first=<unavailable>, __last=<unavailable>) at stl_construct.h:195:7
    frame #14: 0x0000aaaad784b5a0 duckling`duckdb::RowGroup::~RowGroup() [inlined] void std::_Destroy<duckdb::shared_ptr<duckdb::ColumnData, true>*, duckdb::shared_ptr<duckdb::ColumnData, true>>(__first=<unavailable>, __last=<unavailable>, (null)=<unavailable>) at alloc_traits.h:848:7
    frame #15: 0x0000aaaad784b5a0 duckling`duckdb::RowGroup::~RowGroup() [inlined] std::vector<duckdb::shared_ptr<duckdb::ColumnData, true>, std::allocator<duckdb::shared_ptr<duckdb::ColumnData, true>>>::~vector(this=<unavailable>) at stl_vector.h:680:2
    frame #16: 0x0000aaaad784b5a0 duckling`duckdb::RowGroup::~RowGroup(this=<unavailable>) at row_group.cpp:83:1
    frame #17: 0x0000aaaad786ee18 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] std::default_delete<duckdb::RowGroup>::operator()(this=0x0000aaacbb73e1a8, __ptr=0x0000aaab75ae7860) const at unique_ptr.h:85:2
    frame #18: 0x0000aaaad786ee10 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() at unique_ptr.h:361:4
    frame #19: 0x0000aaaad786ee08 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] duckdb::SegmentNode<duckdb::RowGroup>::~SegmentNode(this=0x0000aaacbb73e1a0) at segment_tree.hpp:21:8
    frame #20: 0x0000aaaad786ee08 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] void std::_Destroy<duckdb::SegmentNode<duckdb::RowGroup>>(__pointer=0x0000aaacbb73e1a0) at stl_construct.h:151:19
    frame #21: 0x0000aaaad786ee08 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] void std::_Destroy_aux<false>::__destroy<duckdb::SegmentNode<duckdb::RowGroup>*>(__first=0x0000aaacbb73e1a0, __last=0x0000aaacbb751130) at stl_construct.h:163:6
    frame #22: 0x0000aaaad786ede8 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] void std::_Destroy<duckdb::SegmentNode<duckdb::RowGroup>*>(__first=<unavailable>, __last=0x0000aaacbb751130) at stl_construct.h:195:7
    frame #23: 0x0000aaaad786ede8 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector() [inlined] void std::_Destroy<duckdb::SegmentNode<duckdb::RowGroup>*, duckdb::SegmentNode<duckdb::RowGroup>>(__first=<unavailable>, __last=0x0000aaacbb751130, (null)=0x0000fffefc81a908) at alloc_traits.h:848:7
    frame #24: 0x0000aaaad786ede8 duckling`std::vector<duckdb::SegmentNode<duckdb::RowGroup>, std::allocator<duckdb::SegmentNode<duckdb::RowGroup>>>::~vector(this=size=4883) at stl_vector.h:680:2
    frame #25: 0x0000aaaad7857f74 duckling`duckdb::RowGroupCollection::Checkpoint(this=<unavailable>, writer=<unavailable>, global_stats=0x0000fffefc81a9c0) at row_group_collection.cpp:1017:1
    frame #26: 0x0000aaaad788f02c duckling`duckdb::DataTable::Checkpoint(this=0x0000aaab04649e70, writer=0x0000aaab6584ea80, serializer=0x0000fffefc81ab38) at data_table.cpp:1427:14
    frame #27: 0x0000aaaad7881394 duckling`duckdb::SingleFileCheckpointWriter::WriteTable(this=0x0000fffefc81b128, table=0x0000aaab023b78c0, serializer=0x0000fffefc81ab38) at checkpoint_manager.cpp:528:11
    frame #28: 0x0000aaaad787ece4 duckling`duckdb::SingleFileCheckpointWriter::CreateCheckpoint() [inlined] duckdb::SingleFileCheckpointWriter::CreateCheckpoint(this=<unavailable>, obj=0x0000fffefc81ab38)::$_7::operator()(duckdb::Serializer::List&, unsigned long) const::'lambda'(duckdb::Serializer&)::operator()(duckdb::Serializer&) const at checkpoint_manager.cpp:181:43
    frame #29: 0x0000aaaad787ecd8 duckling`duckdb::SingleFileCheckpointWriter::CreateCheckpoint() [inlined] void duckdb::Serializer::List::WriteObject<duckdb::SingleFileCheckpointWriter::CreateCheckpoint()::$_7::operator()(duckdb::Serializer::List&, unsigned long) const::'lambda'(duckdb::Serializer&)>(this=<unavailable>, f=(unnamed class) @ 0x0000600002cbd2b0) at serializer.hpp:385:2
    frame #30: 0x0000aaaad787ecc4 duckling`duckdb::SingleFileCheckpointWriter::CreateCheckpoint() [inlined] duckdb::SingleFileCheckpointWriter::CreateCheckpoint()::$_7::operator()(this=<unavailable>, list=<unavailable>, i=2) const at checkpoint_manager.cpp:181:8
    frame #31: 0x0000aaaad787ecb0 duckling`duckdb::SingleFileCheckpointWriter::CreateCheckpoint() at serializer.hpp:151:4
    frame #32: 0x0000aaaad787ec94 duckling`duckdb::SingleFileCheckpointWriter::CreateCheckpoint(this=0x0000fffefc81b128) at checkpoint_manager.cpp:179:13
    frame #33: 0x0000aaaad78954a8 duckling`duckdb::SingleFileStorageManager::CreateCheckpoint(this=0x0000aaaafe1de140, options=(wal_action = DONT_DELETE_WAL, action = CHECKPOINT_IF_REQUIRED, type = FULL_CHECKPOINT)) at storage_manager.cpp:365:17
    frame #34: 0x0000aaaad78baac0 duckling`duckdb::DuckTransactionManager::Checkpoint(this=0x0000aaaafe167e00, context=<unavailable>, force=<unavailable>) at duck_transaction_manager.cpp:198:18
    frame #35: 0x0000aaaad69d02c0 duckling`md::Server::BackgroundCheckpointIfNeeded(this=0x0000aaaafdbfe900) at server.cpp:1983:31
    frame #36: 0x0000aaaadac5d3f0 duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] std::function<void ()>::operator()(this=<unavailable>) const at std_function.h:590:9
    frame #37: 0x0000aaaadac5d3e0 duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] md::BackgroundCronTask::Start(unsigned long)::$_0::operator()(this=0x0000aaaafdf169a8) const at background_cron_task.cpp:25:4
    frame #38: 0x0000aaaadac5d30c duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] void std::__invoke_impl<void, md::BackgroundCronTask::Start(unsigned long)::$_0>((null)=<unavailable>, __f=0x0000aaaafdf169a8) at invoke.h:61:14
    frame #39: 0x0000aaaadac5d30c duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] std::__invoke_result<md::BackgroundCronTask::Start(unsigned long)::$_0>::type std::__invoke<md::BackgroundCronTask::Start(unsigned long)::$_0>(__fn=0x0000aaaafdf169a8) at invoke.h:96:14
    frame #40: 0x0000aaaadac5d30c duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] void std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>::_M_invoke<0ul>(this=0x0000aaaafdf169a8, (null)=<unavailable>) at std_thread.h:259:13
    frame #41: 0x0000aaaadac5d30c duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run() [inlined] std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>::operator()(this=0x0000aaaafdf169a8) at std_thread.h:266:11
    frame #42: 0x0000aaaadac5d30c duckling`std::thread::_State_impl<std::thread::_Invoker<std::tuple<md::BackgroundCronTask::Start(unsigned long)::$_0>>>::_M_run(this=0x0000aaaafdf169a0) at std_thread.h:211:13
    frame #43: 0x0000ffff91a031fc
    frame #44: 0x0000ffff91c0d5c8
```

The problem is that if there's an IO exception being thrown in
`RowGroupCollection::Checkpoint` after some (but not all) checkpoint
tasks have been scheduled but before
`checkpoint_state.executor.WorkOnTasks();` is called, it results in an
InternalException / DuckDB crash as the `Checkpoint ` method does not
wait for the scheduled tasks to have completed before destroying the
referenced resources.
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@Tmonster