Docs: correct join_algorithm default (not auto)#6450
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The default in source (ClickHouse/ClickHouse src/Core/Settings.cpp) is `direct,parallel_hash,hash`, not `auto`.
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Blargian
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Jun 25, 2026
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Docs PR opened: ClickHouse/mintlify-docs-dev#281 Corrected the JOINs best practices page to show the real join_algorithm default is direct,parallel_hash,hash instead of auto. |
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Summary
The "Minimize and optimize JOINs" best-practices page states that
join_algorithm = 'auto'is the default. The actual default in source isdirect,parallel_hash,hash— seesrc/Core/Settings.cpp(DECLARE(JoinAlgorithm, join_algorithm, "direct,parallel_hash,hash", ...)).This corrects the statement and notes the real default and what it means (direct join when the right-hand side is a dictionary/key-value engine, otherwise parallel hash, then hash). One-sentence prose change; no URL/anchor change.
Checklist
ClickHouse/ClickHousesource