How can I model percentile aggregates (10th percentile, 90th percentile, etc.) for individual fields in Clickhouse?

You can define percentile aggregates using ClickHouse’s native functions without needing number_agg. For example, to model the 90th percentile of a latency_ms field, use:

- name: latency_p90_ms  
  type: number  
  sql: quantile(0.9)(latency_ms)

This works directly with the number type and supports custom window functions like percentiles.