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Migration: correct join_algorithm default in JOINs best practices #281

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Blargian merged 1 commit into from
Jun 26, 2026
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Migration: correct join_algorithm default in JOINs best practices #281

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2 changes: 1 addition & 1 deletion concepts/best-practices/minimize-optimize-joins.mdx
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Expand Up @@ -58,7 +58,7 @@ ClickHouse supports several JOIN algorithms that trade off between speed and mem
Each algorithm has varying support for JOIN types. A full list of supported join types for each algorithm can be found [here](/concepts/features/operations/select/joining-tables#choosing-a-join-algorithm).
</Note>

You can let ClickHouse choose the best algorithm by setting `join_algorithm = 'auto'` (the default), or explicitly control it based on your workload. If you need to select a join algorithm to optimize for performance or memory overhead, we recommend [this guide](/concepts/features/operations/select/joining-tables#choosing-a-join-algorithm).
You can let ClickHouse choose the best algorithm by setting `join_algorithm = 'auto'`, or explicitly control it based on your workload. The default value is `direct,parallel_hash,hash`, so ClickHouse uses a direct join when the right-hand side is a dictionary or key-value engine and otherwise falls back to parallel hash, then hash. If you need to select a join algorithm to optimize for performance or memory overhead, we recommend [this guide](/concepts/features/operations/select/joining-tables#choosing-a-join-algorithm).

For optimal performance:

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