Problemsby GlyphTrouble with ClickHouse merges
2 posts from 2 people2d activeSteady, +1 this weekunverified
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The posts behind it
OPTIMIZE FINAL writes the merged part with stale metadata after waiting for running merges
`OPTIMIZE FINAL` on `MergeTree` reads its metadata snapshot once, before waiting for running merges. A `RENAME COLUMN` that commits while it waits publishes new metadata and registers its mutation. The retried selection sees the mutation and records its version in the merged...
Backport #100822 to 26.3: ATTACH PARTITION FROM aborts merges in other partitions
### Company or project name Shopify ### Describe what's wrong On 26.3, `ALTER TABLE dst ATTACH PARTITION X FROM src` on a non-replicated MergeTree aborts every running merge on `dst`, also merges in other partitions. The aborted merges end with Code 236 (ABORTED). No new merge...
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About this problem
Evidence
2 posts from 2 people in 1 place, about 1 a week over 13 days. Mostly on ClickHouse/ClickHouse. Tools named alongside: GitHub.
Frustration Frustration 0 of 3· Seen on GitHub issues
How it was grouped
Posts about ClickHouse with no known issue, sharing the word "merges". First post Oct 22, 2026, latest Nov 3, 2026. Unverified: fewer than 3 posts, or one person or place only. Method
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