Convert to FixedHashTable for hash join with small int key range by m-selmi · Pull Request #99275 · ClickHouse/ClickHouse · GitHub
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Convert to FixedHashTable for hash join with small int key range #99275

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m-selmi merged 50 commits into
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m-selmi:introduce-fixed-range-hash-table
Apr 17, 2026
Merged

Convert to FixedHashTable for hash join with small int key range #99275
m-selmi merged 50 commits into
ClickHouse:masterfrom
m-selmi:introduce-fixed-range-hash-table

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@m-selmi

@m-selmi m-selmi commented Mar 11, 2026 •
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relates to #41398 ( #97882 )

In case the join keys of a hash join are integers with a small range, the hash table can be replaced with an array indexed by key - min_key. This should have:

  • better lookup path
  • lower memory for dense keys

Capping the optimization at build size 2^18 makes the overhead of converting the hash table below 15 ms. In a follow up we can extract the min/max from statistics and directly build the direct lookup hash table to allow larger build sides.

Performance test:

LEFT JOIN with low selectivity:

display-name    0       SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 0       join_convert_to_fixed_hash_table.query0.prewarm0        0       0.1833493709564209
query   0       join_convert_to_fixed_hash_table.query0.run0    0       0.18002748489379883
query   0       join_convert_to_fixed_hash_table.query0.run1    0       0.18134760856628418
query   0       join_convert_to_fixed_hash_table.query0.run2    0       0.16283226013183594
...
median  0       0.18008053302764893
display-name    1       SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 1       join_convert_to_fixed_hash_table.query1.prewarm0        0       0.12644457817077637
query   1       join_convert_to_fixed_hash_table.query1.run0    0       0.1271359920501709
query   1       join_convert_to_fixed_hash_table.query1.run1    0       0.12077617645263672
query   1       join_convert_to_fixed_hash_table.query1.run2    0       0.12066817283630371
...
median  1       0.12168383598327637

display-name    2       SELECT p.id1, b.id1 FROM probe p LEFT JOIN build_10k b ON p.id1 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 2       join_convert_to_fixed_hash_table.query2.prewarm0        0       0.19025063514709473
query   2       join_convert_to_fixed_hash_table.query2.run0    0       0.18439221382141113
query   2       join_convert_to_fixed_hash_table.query2.run1    0       0.18043732643127441
query   2       join_convert_to_fixed_hash_table.query2.run2    0       0.18224787712097168
...
median  2       0.18065476417541504
display-name    3       SELECT p.id1, b.id1 FROM probe p LEFT JOIN build_10k b ON p.id1 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 3       join_convert_to_fixed_hash_table.query3.prewarm0        0       0.12453508377075195
query   3       join_convert_to_fixed_hash_table.query3.run0    0       0.12838315963745117
query   3       join_convert_to_fixed_hash_table.query3.run1    0       0.12383294105529785
query   3       join_convert_to_fixed_hash_table.query3.run2    0       0.1149449348449707
...
median  3       0.12236618995666504

display-name    4       SELECT p.id2, b.id2 FROM probe p LEFT JOIN build_50k b ON p.id2 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 4       join_convert_to_fixed_hash_table.query4.prewarm0        0       0.14774322509765625
query   4       join_convert_to_fixed_hash_table.query4.run0    0       0.14944934844970703
query   4       join_convert_to_fixed_hash_table.query4.run1    0       0.14705681800842285
query   4       join_convert_to_fixed_hash_table.query4.run2    0       0.13262701034545898
...
median  4       0.14212524890899658
display-name    5       SELECT p.id2, b.id2 FROM probe p LEFT JOIN build_50k b ON p.id2 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 5       join_convert_to_fixed_hash_table.query5.prewarm0        0       0.12196063995361328
query   5       join_convert_to_fixed_hash_table.query5.run0    0       0.13278698921203613
query   5       join_convert_to_fixed_hash_table.query5.run1    0       0.11975955963134766
query   5       join_convert_to_fixed_hash_table.query5.run2    0       0.12914061546325684
...
median  5       0.12599778175354004

INNER JOIN with low selectivity:

display-name    6       SELECT p.id0, b.id0 FROM probe p INNER JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 6       join_convert_to_fixed_hash_table.query6.prewarm0        0       0.10300731658935547
query   6       join_convert_to_fixed_hash_table.query6.run0    0       0.09830045700073242
query   6       join_convert_to_fixed_hash_table.query6.run1    0       0.0974583625793457
query   6       join_convert_to_fixed_hash_table.query6.run2    0       0.1009521484375
...
median  6       0.0974583625793457
display-name    7       SELECT p.id0, b.id0 FROM probe p INNER JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 7       join_convert_to_fixed_hash_table.query7.prewarm0        0       0.10037946701049805
query   7       join_convert_to_fixed_hash_table.query7.run0    0       0.10163545608520508
query   7       join_convert_to_fixed_hash_table.query7.run1    0       0.09937071800231934
query   7       join_convert_to_fixed_hash_table.query7.run2    0       0.09917187690734863
...
median  7       0.09790253639221191

display-name    8       SELECT p.id1, b.id1 FROM probe p INNER JOIN build_10k b ON p.id1 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 8       join_convert_to_fixed_hash_table.query8.prewarm0        0       0.10841727256774902
query   8       join_convert_to_fixed_hash_table.query8.run0    0       0.1069483757019043
query   8       join_convert_to_fixed_hash_table.query8.run1    0       0.10824179649353027
query   8       join_convert_to_fixed_hash_table.query8.run2    0       0.10557150840759277
...
median  8       0.10654354095458984
display-name    9       SELECT p.id1, b.id1 FROM probe p INNER JOIN build_10k b ON p.id1 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 9       join_convert_to_fixed_hash_table.query9.prewarm0        0       0.10459399223327637
query   9       join_convert_to_fixed_hash_table.query9.run0    0       0.10324239730834961
query   9       join_convert_to_fixed_hash_table.query9.run1    0       0.10093092918395996
query   9       join_convert_to_fixed_hash_table.query9.run2    0       0.10028290748596191
...
median  9       0.10217082500457764

display-name    10      SELECT p.id2, b.id2 FROM probe p INNER JOIN build_50k b ON p.id2 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 10      join_convert_to_fixed_hash_table.query10.prewarm0       0       0.16778898239135742
query   10      join_convert_to_fixed_hash_table.query10.run0   0       0.16060996055603027
query   10      join_convert_to_fixed_hash_table.query10.run1   0       0.15985321998596191
query   10      join_convert_to_fixed_hash_table.query10.run2   0       0.15698528289794922
...
median  10      0.15985321998596191
display-name    11      SELECT p.id2, b.id2 FROM probe p INNER JOIN build_50k b ON p.id2 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 11      join_convert_to_fixed_hash_table.query11.prewarm0       0       0.1654071807861328
query   11      join_convert_to_fixed_hash_table.query11.run0   0       0.16226959228515625
query   11      join_convert_to_fixed_hash_table.query11.run1   0       0.15493321418762207
query   11      join_convert_to_fixed_hash_table.query11.run2   0       0.16113018989562988
...
median  11      0.16113018989562988

LEFT JOIN with high selectivity:

display-name    12      SELECT p.id3, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id3 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 12      join_convert_to_fixed_hash_table.query12.prewarm0       0       0.14415192604064941
query   12      join_convert_to_fixed_hash_table.query12.run0   0       0.15161943435668945
query   12      join_convert_to_fixed_hash_table.query12.run1   0       0.1386244297027588
query   12      join_convert_to_fixed_hash_table.query12.run2   0       0.16128015518188477
...
median  12      0.15161943435668945
display-name    13      SELECT p.id3, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id3 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 13      join_convert_to_fixed_hash_table.query13.prewarm0       0       0.14345049858093262
query   13      join_convert_to_fixed_hash_table.query13.run0   0       0.14605355262756348
query   13      join_convert_to_fixed_hash_table.query13.run1   0       0.14837956428527832
query   13      join_convert_to_fixed_hash_table.query13.run2   0       0.14568734169006348
...
median  13      0.14000260829925537

display-name    14      SELECT p.id4, b.id1 FROM probe p LEFT JOIN build_10k b ON p.id4 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 14      join_convert_to_fixed_hash_table.query14.prewarm0       0       0.16616034507751465
query   14      join_convert_to_fixed_hash_table.query14.run0   0       0.1880347728729248
query   14      join_convert_to_fixed_hash_table.query14.run1   0       0.1839582920074463
query   14      join_convert_to_fixed_hash_table.query14.run2   0       0.18306493759155273
...
median  14      0.18138229846954346
display-name    15      SELECT p.id4, b.id1 FROM probe p LEFT JOIN build_10k b ON p.id4 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 15      join_convert_to_fixed_hash_table.query15.prewarm0       0       0.14579486846923828
query   15      join_convert_to_fixed_hash_table.query15.run0   0       0.13248085975646973
query   15      join_convert_to_fixed_hash_table.query15.run1   0       0.1412487030029297
query   15      join_convert_to_fixed_hash_table.query15.run2   0       0.14390993118286133
...
median  15      0.1425793170928955

display-name    16      SELECT p.id5, b.id2 FROM probe p LEFT JOIN build_50k b ON p.id5 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 16      join_convert_to_fixed_hash_table.query16.prewarm0       0       0.16441607475280762
query   16      join_convert_to_fixed_hash_table.query16.run0   0       0.1532902717590332
query   16      join_convert_to_fixed_hash_table.query16.run1   0       0.14643335342407227
query   16      join_convert_to_fixed_hash_table.query16.run2   0       0.16123247146606445
...
median  16      0.1532902717590332
display-name    17      SELECT p.id5, b.id2 FROM probe p LEFT JOIN build_50k b ON p.id5 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 17      join_convert_to_fixed_hash_table.query17.prewarm0       0       0.15385031700134277
query   17      join_convert_to_fixed_hash_table.query17.run0   0       0.14410138130187988
query   17      join_convert_to_fixed_hash_table.query17.run1   0       0.1515960693359375
query   17      join_convert_to_fixed_hash_table.query17.run2   0       0.1638193130493164
...
median  17      0.1515960693359375

INNER JOIN with high selectivity:

display-name    18      SELECT p.id3, b.id0 FROM probe p INNER JOIN build_5k b ON p.id3 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 18      join_convert_to_fixed_hash_table.query18.prewarm0       0       0.11940765380859375
query   18      join_convert_to_fixed_hash_table.query18.run0   0       0.13257837295532227
query   18      join_convert_to_fixed_hash_table.query18.run1   0       0.12779712677001953
query   18      join_convert_to_fixed_hash_table.query18.run2   0       0.11160945892333984
...
median  18      0.12434077262878418
display-name    19      SELECT p.id3, b.id0 FROM probe p INNER JOIN build_5k b ON p.id3 = b.id0 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 19      join_convert_to_fixed_hash_table.query19.prewarm0       0       0.11430478096008301
query   19      join_convert_to_fixed_hash_table.query19.run0   0       0.10935091972351074
query   19      join_convert_to_fixed_hash_table.query19.run1   0       0.11330628395080566
query   19      join_convert_to_fixed_hash_table.query19.run2   0       0.11635708808898926
...
median  19      0.11755609512329102

display-name    20      SELECT p.id4, b.id1 FROM probe p INNER JOIN build_10k b ON p.id4 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 20      join_convert_to_fixed_hash_table.query20.prewarm0       0       0.15051937103271484
query   20      join_convert_to_fixed_hash_table.query20.run0   0       0.1494441032409668
query   20      join_convert_to_fixed_hash_table.query20.run1   0       0.14615678787231445
query   20      join_convert_to_fixed_hash_table.query20.run2   0       0.14452171325683594
...
median  20      0.1487886905670166
display-name    21      SELECT p.id4, b.id1 FROM probe p INNER JOIN build_10k b ON p.id4 = b.id1 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 21      join_convert_to_fixed_hash_table.query21.prewarm0       0       0.12285161018371582
query   21      join_convert_to_fixed_hash_table.query21.run0   0       0.12460541725158691
query   21      join_convert_to_fixed_hash_table.query21.run1   0       0.11370539665222168
query   21      join_convert_to_fixed_hash_table.query21.run2   0       0.11903834342956543
...
median  21      0.11821508407592773

display-name    22      SELECT p.id5, b.id2 FROM probe p INNER JOIN build_50k b ON p.id5 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 0
prewarm 22      join_convert_to_fixed_hash_table.query22.prewarm0       0       0.16051506996154785
query   22      join_convert_to_fixed_hash_table.query22.run0   0       0.14917421340942383
query   22      join_convert_to_fixed_hash_table.query22.run1   0       0.13174080848693848
query   22      join_convert_to_fixed_hash_table.query22.run2   0       0.13836169242858887
...
median  22      0.1380230188369751
display-name    23      SELECT p.id5, b.id2 FROM probe p INNER JOIN build_50k b ON p.id5 = b.id2 FORMAT Null SETTINGS join_algorithm = 'hash', enable_join_fixed_hash_table_conversion = 1
prewarm 23      join_convert_to_fixed_hash_table.query23.prewarm0       0       0.15680718421936035
query   23      join_convert_to_fixed_hash_table.query23.run0   0       0.132246732711792
query   23      join_convert_to_fixed_hash_table.query23.run1   0       0.13514304161071777
query   23      join_convert_to_fixed_hash_table.query23.run2   0       0.12445354461669922
...
median  23      0.13214659690856934

LEFT JOIN with auto algorithm:

display-name    24      SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'auto', enable_join_fixed_hash_table_conversion = 0
prewarm 24      join_convert_to_fixed_hash_table.query24.prewarm0       0       0.18239378929138184
query   24      join_convert_to_fixed_hash_table.query24.run0   0       0.17319464683532715
query   24      join_convert_to_fixed_hash_table.query24.run1   0       0.17351984977722168
query   24      join_convert_to_fixed_hash_table.query24.run2   0       0.1790151596069336
...
median  24      0.17514097690582275
display-name    25      SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'auto', enable_join_fixed_hash_table_conversion = 1
prewarm 25      join_convert_to_fixed_hash_table.query25.prewarm0       0       0.11603116989135742
query   25      join_convert_to_fixed_hash_table.query25.run0   0       0.12669825553894043
query   25      join_convert_to_fixed_hash_table.query25.run1   0       0.12326169013977051
query   25      join_convert_to_fixed_hash_table.query25.run2   0       0.11374425888061523
...
median  25      0.12250781059265137

LEFT JOIN with grace_hash algorithm:

display-name    26      SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'grace_hash', enable_join_fixed_hash_table_conversion = 0
prewarm 26      join_convert_to_fixed_hash_table.query26.prewarm0       0       0.221663236618042
query   26      join_convert_to_fixed_hash_table.query26.run0   0       0.19127869606018066
query   26      join_convert_to_fixed_hash_table.query26.run1   0       0.20809626579284668
query   26      join_convert_to_fixed_hash_table.query26.run2   0       0.20948457717895508
...
median  26      0.20255231857299805
display-name    27      SELECT p.id0, b.id0 FROM probe p LEFT JOIN build_5k b ON p.id0 = b.id0 FORMAT Null SETTINGS join_algorithm = 'grace_hash', enable_join_fixed_hash_table_conversion = 1
prewarm 27      join_convert_to_fixed_hash_table.query27.prewarm0       0       0.16614127159118652
query   27      join_convert_to_fixed_hash_table.query27.run0   0       0.15943193435668945
query   27      join_convert_to_fixed_hash_table.query27.run1   0       0.15614867210388184
query   27      join_convert_to_fixed_hash_table.query27.run2   0       0.1661539077758789
...
median  27      0.15943193435668945

Changelog category (leave one):

  • Performance Improvement

Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):

Speedup hash join on int32 and int64 keys with small range by using a direct-index hash table.

Documentation entry for user-facing changes

  • Documentation is written (mandatory for new features)

Note

Medium Risk
Changes hash join’s in-memory data structure for single Int32/Int64 key joins by optionally converting to a direct-indexed range table, which can affect join performance/memory and introduces new edge-case paths (range bounds, signed/unsigned handling). Scope is limited by size/range guards, a hard allocation cap, and added tests.

Overview
Adds a new hash-join optimization for single integer keys with a small value range: after building a HashJoin right-side map (key32/key64), the join can convert it into a flat FixedRangeHashMap indexed by key - min_key (skipping ASOF and multi-map cases, with signed min/max handling).

Introduces FixedRangeHashTable/FixedRangeHashMap implementations, new join variants range_key32/range_key64, and instruments conversion time via ProfileEvents::BuiltJoinRangeHashMapMicroseconds plus a debug log.

Adds settings enable_fixed_range_hash_table and fixed_range_hash_table_max_size (propagated through query plan serialization and join settings, with a safety cap in TableJoin), and includes performance + stateless tests to validate triggering and result correctness.

Written by Cursor Bugbot for commit fb869f2. This will update automatically on new commits. Configure here.

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@clickhouse-gh clickhouse-gh Bot added the pr-performance Pull request with some performance improvements label Mar 11, 2026
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@m-selmi m-selmi requested a review from Copilot March 12, 2026 16:01
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Pull request overview

This PR adds an optimization for hash joins on single Int32/Int64 keys with a small value range by converting the build-side hash map into a direct-indexed (range) table, controlled by new settings and validated with new tests/benchmarks.

Changes:

  • Implement FixedRangeHashTable/FixedRangeHashMap and add new HashJoin variants (range_key32/range_key64) plus post-build conversion logic.
  • Introduce settings enable_fixed_range_hash_table and fixed_range_hash_table_max_size (including query plan serialization plumbing and a new profile event).
  • Add stateless and performance tests for correctness and performance characterization.

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 6 comments.

Show a summary per file
File Description
tests/queries/0_stateless/04029_join_fixed_range_hash_table.sql New stateless test for conversion trigger + join result correctness.
tests/queries/0_stateless/04029_join_fixed_range_hash_table.reference Expected output for the new stateless test.
tests/performance/join_with_fixed_range_hash_table.xml New perf test workload for comparing fixed-range vs normal hash join.
src/Processors/Transforms/JoiningTransform.cpp Trigger fixed-range conversion at end of build phase for HashJoin.
src/Processors/QueryPlan/QueryPlanSerializationSettings.cpp Add new join-related settings to plan serialization settings.
src/Interpreters/TableJoin.h Store new fixed-range settings in TableJoin and expose accessors.
src/Interpreters/TableJoin.cpp Read/cap new settings from Settings/JoinSettings into TableJoin.
src/Interpreters/JoinOperator.h Add new settings fields to JoinSettings.
src/Interpreters/JoinOperator.cpp Plumb new settings from Settings ↔ QueryPlanSerializationSettings.
src/Interpreters/HashJoin/KeyGetter.h Add key getter mappings for new range key types.
src/Interpreters/HashJoin/HashJoin.h Add range key variants and map storage for FixedRangeHashMap.
src/Interpreters/HashJoin/HashJoin.cpp Implement conversion logic + new profile event + debug log.
src/Core/SettingsChangesHistory.cpp Record compatibility history entries for the new settings.
src/Core/Settings.cpp Define the new Settings entries and defaults.
src/Common/ProfileEvents.cpp Register BuiltJoinRangeHashMapMicroseconds profile event.
src/Common/HashTable/FixedRangeHashTable.h New direct-index table implementation used by the optimization.
src/Common/HashTable/FixedRangeHashMap.h New map wrapper over FixedRangeHashTable for HashJoin use.
src/Common/HashTable/FixedHashMapCell.h Extract FixedHashMapCell into a separate header for reuse.
src/Common/HashTable/FixedHashMap.h Include the extracted FixedHashMapCell header.

Comment thread src/Core/SettingsChangesHistory.cpp Outdated
Comment thread tests/queries/0_stateless/04029_join_convert_to_fixed_hash_table.sql
Comment thread src/Interpreters/TableJoin.cpp Outdated
Comment thread src/Interpreters/HashJoin/HashJoin.cpp Outdated
Comment thread src/Common/HashTable/FixedRangeHashTable.h Outdated
Comment thread src/Common/HashTable/FixedRangeHashTable.h Outdated
@m-selmi m-selmi marked this pull request as ready for review March 13, 2026 09:21
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Comment thread src/Common/HashTable/FixedRangeHashTable.h Outdated
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Comment thread src/Interpreters/TableJoin.cpp Outdated
@m-selmi m-selmi requested a review from vdimir March 13, 2026 09:41
@alexey-milovidov

alexey-milovidov commented Apr 9, 2026

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The AST fuzzer (arm_asan_ubsan) failure is a known flaky UBSan issue in BSINumericIndexedVector. Fix: #100086.

@alexey-milovidov

alexey-milovidov commented Apr 9, 2026

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Azure tests are fixed in #100980, you can update the branch to include the fixes.

@alexey-milovidov

alexey-milovidov commented Apr 10, 2026

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The flaky check failure is fixed in #102148, let's update the branch.

@nickitat

nickitat commented Apr 13, 2026

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Besides the onBuildPhaseFinish situation, LGTM

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clickhouse-gh Bot reviewed Apr 14, 2026
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Comment thread src/Interpreters/GraceHashJoin.cpp
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Comment thread tests/performance/join_convert_to_fixed_hash_table.xml
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Comment thread src/Interpreters/HashJoin/HashJoin.cpp
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Comment thread src/Interpreters/HashJoin/HashJoin.cpp
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clickhouse-gh Bot commented Apr 16, 2026

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LLVM Coverage Report

Metric Baseline Current Δ
Lines 84.00% 84.00% +0.00%
Functions 90.90% 91.10% +0.20%
Branches 76.50% 76.50% +0.00%

Changed lines: 94.51% (258/273) · Uncovered code

Full report · Diff report

@m-selmi m-selmi added this pull request to the merge queue Apr 17, 2026
Merged via the queue into ClickHouse:master with commit 533498e Apr 17, 2026
316 of 318 checks passed
@m-selmi m-selmi deleted the introduce-fixed-range-hash-table branch April 17, 2026 07:59
@robot-ch-test-poll2 robot-ch-test-poll2 added the pr-synced-to-cloud The PR is synced to the cloud repo label Apr 17, 2026
@harikrishnan94 harikrishnan94 mentioned this pull request May 11, 2026
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@UnamedRus UnamedRus mentioned this pull request May 11, 2026
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@wudidapaopao wudidapaopao mentioned this pull request May 22, 2026
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pr-performance Pull request with some performance improvements pr-synced-to-cloud The PR is synced to the cloud repo

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