High-cardinality illustration

High-cardinality

All articles tagged 'High-cardinality'

High Cardinality in ClickHouse at Scale: What Actually Breaks

High Cardinality in ClickHouse at Scale: What Actually Breaks

ClickHouse swallows high-cardinality telemetry at ingest, then breaks at query time weeks later. Here is what fails, and how we keep it fast in production.

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Prathamesh Sonpatki

Prathamesh Sonpatki

ClickHouse LowCardinality: When It Helps and When It Hurts

ClickHouse LowCardinality: When It Helps and When It Hurts

ClickHouse LowCardinality cuts storage and speeds up queries on low-cardinality columns, but backfires on trace IDs. How to tell the difference.

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Prathamesh Sonpatki

Prathamesh Sonpatki