Problemsby GlyphTrouble with ClickHouse query
4 posts from 3 people4d activeFading, +0 this week
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The posts behind it
Plan-based parallel replicas: three plan optimizations are switched off for every query, not only for steps that are shipped
With `parallel_replicas_plan_based = 1`, `QueryPlanOptimizationSettings::enable_parallel_replicas` is set for every query, and three optimizations return early on it: - filter fusion into `ARRAY JOIN` (`fuseFilterIntoArrayJoin.cpp`); - lazy materialization over joins...
Memory tracker counts jemalloc's freed pages as used, so a heavy query started right after another spills to disk
### Describe the situation After a large query, the memory tracker still counts pages jemalloc keeps for reuse as used, so a heavy query started right after it sees too little free memory and spills GROUP BY to disk. Not counting them stops the spills: back-to-back ClickBench...
`file()` TopK query condition cache key omits `use_hive_partitioning`
### Describe what's wrong - The same the statement below returns `[]` under `use_hive_partitioning = 0` right after a run with `use_hive_partitioning = 1`. - Correct answer (cache off) is `[999,998,997]`. - The reverse order fails too. Root cause: #122127 lets Nil-UUID `File`...
Row policy with DateTime64/Time64 query parameter re-parses to wrong value
### Describe what's wrong - A row policy created with a `DateTime64` or `Time64` query parameter does not keep the value it was created with. - Trigger: `CREATE ROW POLICY ... USING ts Analysis details (evidence, affected locations, impact) Why we believe this is a bug:...
Companies and products named
About this problem
Evidence
4 posts from 3 people in 1 place, about 2 a week over 11 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 "query". First post Oct 22, 2026, latest Nov 1, 2026. Corroborated: 3 or more posts from 2 or more people or places. Method
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History