Problemsby GlyphClickHouse streams lag, drop or reorder events
2 posts from 2 people2d activeFading, +0 this weekunverified
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The posts behind it
Synchronising across multiple topics
We're struggling with exactly how to handle consuming data across three single topic partitions. The data is being written to a DB (ClickHouse in this case but not relevant). The data is produced by three separate producers who under normal conditions will write a 'set' of data...
`ARRAY JOIN` with a view boundary between fail with `TYPE_MISMATCH`
### Company or project name _No response_ ### Describe what's wrong A valid query fails to plan when three things meet: 1. A view's body has an `ARRAY JOIN`. `ARRAY JOIN [1] AS a` is enough, and it keeps every row exactly once. 2. A second `ARRAY JOIN` reads that view, either in...
Companies and products named
About this problem
Evidence
2 posts from 2 people in 2 places, about 1 a week over 20 days. Mostly on ClickHouse/ClickHouse, r/apachekafka. Tools named alongside: Apache Kafka.
Frustration Frustration 0 of 3· Seen on GitHub issues, Reddit
How it was grouped
Posts that state a pain and match the "streaming" rule about ClickHouse. First post Oct 4, 2026, latest Oct 23, 2026. Unverified: fewer than 3 posts, or one person or place only. Method
The same problem elsewhere
Streaming pipelines lag, drop or reorder events
12 posts from 12 people on GitHub issues, Stack Overflow.
Apache Kafka streams lag, drop or reorder events
2 posts from 2 people on Mastodon, Reddit. Unverified.
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Trouble with ClickHouse read
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Trouble with ClickHouse join
Top post: "Explicit grace_hash now spills at max_bytes_ratio_before_external_join = 0.5 although the build side fits in", one of 4 posts from 3 people on GitHub issues.
Trouble with ClickHouse merge
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ClickHouse rate limits and usage caps block work
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Trouble with ClickHouse null
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History